Naval Aviation

Firsts Leading the way in Innovation Ski-Jump

In the 1970s Lt Cdr Doug Taylor invented the ‘Ski-Jump’. This upwards curving ramp at the forward end of the flight deck ensures that the aircraft is launched on an upward trajectory giving considerable performance gains, including much greater payload and range, than a corresponding flat deck, short take-off. The early trials proved so successful that the Ski-Jump was incorporated into the design of HMS Hermes and the Invincible ClassSRVL carriers.

royalnavy.mod.uk/flynavy100

Shipborne Rolling Vertical Landing 1909 - 2009

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1.0 THE JSF AND CVF PROGRAMS Although the ramp is physically part of the ship and responsibility for its manufacture and installation lies with the ACA, its profile is entirely based on the aircraft characteristics and for this reason the development of a CVF ski-jump ramp profile profile optimised for the F-35B was conducted by the CVF Integration 1.1 Overview of the JSF program Support Team (CVFIST) on behalf of Team JSF in 2006 and 2007. Team JSF (TJSF) comprises Lockheed Martin, BAE Systems and Northrop Grumman and will produce the JSF aircraft in three variants: 1.4 F-35B STOVL lift and propulsion system optimisation for F-35B conventional take-off and landing (CTOL); carrier based variant (CV); and a short take-off and vertical landing (STOVL) aircraft. This paper deals The F-35B has a number of unique elements that facilitate its STOVL with the STOVL aircraft, designated capability, and these are critical in the optimisation of a ski jump ramp F-35B, which is currently selected by the UK as its Joint Combat Aircraft profile for the aircraft. A basic description of the layout and function of the (JCA), to be operated by the Royal Navy and Royal Air Force replacing lift and propulsion system is shown in Fig. 2 and described below: the existing Harrier fleet. ● a Lift Fan driven by a shaft from the main engine which provides A. Fry, R. Cook and N. Revill vertical lift through a variable area vane box nozzle using louvered vanes to vector thrust between vertically downwards and partially aft. [email protected] 1.2 overview of the CVF programme ● a three-bearing swivel module (3BSM), which vectors the main The Future Aircraft Carrier (CVF) programme is managed by the Aircraft engine exhaust thrust from the core engine through vertically Carrier Alliance (ACA), an industry and government consortium, and will downwards to fully aft – the latter being the default for conventional produce two new carrier vessels entering service from 2014 to replace the mode flying. BAE Systems existing Invincible class of ships and is illustrated with the F-35B in Fig. 1. ● roll nozzles, ducted from the engine and exiting in each wing These carriers will act as the UK’s mobile air-base, operating and providing roll control and vertical lift. These are closed off during the Warton supporting a wide variety of aircraft in support of UK expeditionary opera- initial portion of the short take-off (STO) in order to maximise tions – obviating the need to rely on other countries co-operation. The forward thrust from the main engine, opening towards the end of the UK THE AERONAUTICAL JOURNAL FEBRUARY 2009 VOLUME 113 NO 1140 embarked air group will primarily consist of JCA but will also include 79 ramp in order to provide control and lift during the fly out. Airborne Surveillance and Control, Maritime, Support, Attack and Battlefield helicopters depending on the mission. In the Carrier Strike role, up to 36 JCA will be embarked, capable of 2.0 THE SKI JUMP RAMP operating in all weathers, day and night; providing a long range strike capability in addition to air defence and offensive support to the fleet and ground troops. 2.1 Background and history of the ramp

1.3 CVF integration support program The ski jump ramp was conceived by a Royal Navy officer in the 1970s and subsequently developed by the UK services, industry and Government This program and team was established as part of TJSF and tasked to as a way of increasing the STO launch payload for the Harrier. It has since provide existing and newly generated engineering information to support become an integral part of embarked operations for UK and most foreign the ACA in the integration of F-35B with CVF. Harrier operators. The first operational ramp was fitted to HMS Hermes (see Fig. 3) in 1979 and was a 12 degree ramp; as defined by the angle to the horizontal of the tangent at the last point on the profile. The Invincible class of Anti-Submarine Carriers (CVS) were modified during building to accommodate the Sea Harrier aircraft and were ABSTRACT NOMENCLATURE completed with a 7 degree ramp in the early 1980s. This lower angle was chosen to avoid obstructing the firing arcs of the Surface to Air Missile This paper presents a summary of the principles and processes used to 3BSM 3 Bearing swivel module system fitted to this class although giving less launch performance benefit. design a ski-jump ramp profile for the UK’s Future Aircraft Carrier (CVF) ACA aircraft carrier alliance Due in part to the success of the Harrier in the 1982 Falklands war these optimised for the Joint Strike Fighter (JSF). CG centre of gravity ramps were replaced by a larger 12 degree design later in the 1980s. The ships and their ramps have given valuable service to the UK through to this The paper includes an overview of the CVF and JSF programs, a history CTOL conventional take-off and landing day with successive generations of the Harrier family, as Fig. 4 illustrates. and summary of the ski-jump ramp and the principles of its use in the CV carrier variant shipborne Short Take-Off (STO) manoeuvre. CVS anti submarine carrier Invincible The paper discusses the importance of defining optimisation boundaries (descriptor for the class of ships) CVF UK future aircraft carrier project including specified objectives, aircraft configurations and environmental CVFIST CVF integration support team conditions. It then demonstrates the process of balancing the design drivers Figure 1. Artists impression of CVF and F-35B. DEFSTAN UK MoD defence standard publication of air vehicle performance and landing gear loads to achieve an optimum Dstl Defence Science and Technology Laboratory profile. Comparisons are made between the proposed candidate CVF ramp EC environmental condition (e.g. Hot/ISA day) profile and the current in service ski-jump design as designed for the JCA UK joint combat aircraft project Harrier family of aircraft. JSF Joint Strike Fighter The paper briefly covers some of the important issues and factors that SDD system development and design phase have been experienced when a theoretical profile is translated into a STO short take-off physical ramp fitted to a ship, principally the effects on aircraft operations STOVL short take-off and vertical landing due to build and in-service variation from the nominal profile. TJSF Team JSF

Paper No. 3324. Manuscript received 31 July 2008, accepted 16 October 2008. Copyright BAE Systems 2008. All rights reserved. Published by the Royal Aeronautical Society with permission. This paper was originally presented at the 2008 International Powered Lift Conference at The Royal Aeronautical Society, London. Figure 2. F-35B and its STOVL Propulsion and Lift System. Figure 3. HMS Hermes with first 12° ski jump ramp. This margin primarily accounts for variation between the mathematical profile derived during the analysis and the ‘as-built’ steel structure that flexes with the operation of the ship and can develop a permanent defor- mation. Legacy experience is explicit that this build and in-service physical variance can result in gear load increases of a severity requiring operational performance restrictions. Graphically illustrated in Fig. 9, the load margin is obtained by speci- fying a minimum remaining strut stroke in the worst loading case based on legacy experience, applying this to the load/stroke curve and using the Figure 8. Ski-jump launch profile. resulting load/stroke point as the metric against which launch cases are assessed.

Figure 4. HMS Illustrious with retrofitted 12° ramp. Figure 5. Ramp design drivers. 5.0 CHARACTERISATION 2.2 Principles of the ski jump The ski jump ramp works by imparting an upward vertical velocity and ballistic profile to the aircraft, providing additional time to accelerate to 5.1 Performance flying speed whilst ensuring it is on a safe trajectory. This additional time is The sensitivity studies initially used the existing CVS ramp profile as a manifested either in a reduced take-off length for a given weight, or baseline, and showed that the high weight configurations at higher ambient increased weight (i.e. launch performance) for a fixed take-off distance as temperatures were the most stressing in terms of what payload capability in a ship based STO. was achievable. Figure 10 displays a performance characterisation at The additional performance does not come for free, with a significant different environmental conditions (EC 1 to 4) with the CVS ramp, and increase in landing gear loads above those of a standard take off (which are showing the target configuration (weight) is achievable bar the most very low compared to a landing). The increase represents the energy trans- stressing condition. ferred to the aircraft as it translates up the ramp; and if the angle and Figure 9. Landing gear loads/stroke margin. A nominal case from which comparisons could be made against past curvature of the ramp are increased to obtain greater performance benefit, and baseline predictions of performance was developed, as were a range of so are the loads. This is tolerable up to a point because the gear strength is Reference 8 details the work performed by Dstl to examine the key weight cases in order to provide the on-ramp schedules of control effectors defined by landing events and thus has the ability to accept the increased factors and CVF/JCA requirements which influenced this task, in (nozzle angles, thrust split and elevator angle) for use in the landing gear take-off loads, but loads act as an upper boundary on permissible ramp particular, development of the key performance and loads cases in terms of loads analysis. The effects of varying WOD and aircraft CG were also size, as illustrated in Fig. 5. aircraft configurations and environmental conditions which formed the investigated. The ideal landing gear vertical load time history for a ski jump ramp customers objectives. Other ground rules such as take off distances, For the F-35B, optimum scheduling of thrust and control effectors is a STO is sketched in Fig. 6, with a rapid increase to a steady maximum vital component of maximising the performance benefit of a ski jump ramp Figure 6. Ideal and Actual Ramp Landing Gear Vertical Load Profiles. maximum ramp length and height constraints, wind over deck speeds where the area underneath the curve represents the energy imparted by the (WOD) and ship motion factors were also generated prior to the main and this was assumed possible based on SDD practice. Optimum sched- ramp. However, the actual loads are different, and reflect the complex analysis which was based on legacy experience with Harrier analysis, TJSF uling after leaving the ski-jump was achieved using a theory developed by dynamic response of the gear components as they enter and travel up the SDD best practice, and sensitivity studies of performance and loads to Dstl and outlined in Ref. 9. curvature of the profile. identify sensible values and ranges. References 1, 2 and 3 describe in further detail the principles behind the Previous assessments considered pilot view of the sea and deck as well 5.2 Loads ski jump and its advantages as part of a STO manoeuvre compared to a flat as handling qualities which were found to be benign for ski-jump STOs deck launch and the design of the profile is described later. and since they do not drive the design of the ramp, are not discussed For loads, the gear response on entering the ramp is essentially a function It should be noted that non-STOVL aircraft can benefit from a ski jump further. of energy, i.e. mass and speed, and it was necessary to investigate a range manoeuvre, as illustrated by the Russian use of ramps with conventional of weight and speed cases in order to identify the worst case in order to type aircraft from their carriers. STOVL aircraft are unique however then use that as a ‘working’ case for the optimisation phase. This balance is because of the flexible and complex manner in which the thrust and control 4.2 Safe launch metric not intuitive since the highest weights are only achievable with higher effectors generate combinations of thrust and forward speed in conjunction WOD speeds and the gear loading may be offset by the additional wing with the speed dependent wing lift. At the core of a ski jump performance analysis is the assessment of whether a launch case is achievable or not. The minimum safe launch is lift. The opposite case, at lighter weight but with excess deck run and thus defined where the ramp exit speed does not result in any rate of descent high entry speed, was included for balance. during the trajectory until the aircraft has transitioned to fully wing-borne The sensitivity to changes in the control effector scheduling was investi- 3.0 RAMP DESIGN PROCESS flight. This results in the launch profile shown in Fig. 8, with an inflection gated in order to understand how changes to these to optimise for perfor- point at which the criteria for a successful launch are assessed. mance can impact loads – as were centre of gravity (CG) variations, Figure 7 illustrates the overall concept adopted for the design of the CVF There are two safe launch criteria derived from legacy STOVL different WOD speeds, use of external stores (for their aerodynamic drag ramp and this was strongly influenced by the documentary evidence and experience that are used on the JSF program, of which the more stressing is increment effect on speed, forces and moments) and different methods of guidance from previous ramp design tasks. References 4 to 7 and the adopted: (a) subtracting a margin from the WOD and requiring zero sink modelling the strut internal pressures. acknowledgements reflect drawing on past experience and knowledge, and rate (known as Operational WOD); and (b) using the full value of WOD the team’s contribution was to then optimise it to the F-35B aircraft using but requiring a defined positive rate of climb. Both also require a threshold TJSF analysis tools. forward acceleration.

4.0 REQUIREMENTS 4.3 Landing gear loads metric In a ski jump STO event, the gear axle load is almost entirely in the vertical direction represented by Fz. Additionally, because the rate of application of 4.1 Defining optimisation parameters load is relatively slow in comparison to a landing event, the load and stroke An essential first step in the process was to specify criteria that would can be considered to approximately track the airspring force/displacement bound the task and provide measures for driving the design and evaluating curve as shown in Fig. 9. its success. Without having these to reduce the design space to manageable The maximum load and stroke are defined by the limit load and boundaries, optimising for the ‘best’ ramp could be equated to ‘how long is bottoming stroke of the landing gear, but it is necessary to set an optimi- a piece of string ?’. Figure 7. Ramp Design Process. sation metric below this in order to generate an engineering margin. Figure 10. Launch envelope for CVS ramp. To account for ship motion due to the sea state, a delta was added to the gear from uncompressing too quickly. Note that the CVS 12° ramp is value used for gravity (ΔG). This is a legacy approach and replaces the actually now 11·26° as a result of converting the last section of the ramp to huge matrix of pitch, roll and yaw attitudes, velocities and accelerations of a let down – and entailing a slight performance reduction. the ship and aircraft with a single factor. Figure 11 shows the main gear axle load for the worst weight and and speed case at 1G and 1+ΔG, using both short and long ramps of the same 6.4 Profile development exit angle as a way of examining the effect of ramp curvature on gear This looked at a large number of ramp profiles using a wide range of loads. transition length and arc radius values, of which the key conclusions were: This phase of the work demonstrated that for the worst case launch the ● Short transition lengths produce high load overshoot peaks and oscil- CVS ramp would breach the load metrics applied, but also indicated that lations on the first part of the ramp. These outweigh the benefit of using additional length, thus reducing the curvature, could alleviate this. reduced loads from the higher circular arc radius later in the ramp. ● Long transition lengths produce much lower initial load peaks, but to remain within the overall design length the circular arc radius has to 6.0 OPTIMISATION Figure 15. Gear load variation with ramp exit angle. be increased, producing a counteracting load peak. Δ This phase centred on the selection of a ramp exit angle and the shaping of Figure 11. Axle loads for long and short ramps, 1 and 1+ G. The combined effect of varying transition length and circular arc radius the ramp profile to achieve this. is to vary the concentration of curvature in different parts of the ramp. With both of these linked by the requirement to fit an overall length constraint, it was necessary to combine transition length and circular arc radius into a 6.1 Performance single variable, and in Fig. 17 this is plotted against the peak gear loads for the ramps that demonstrated broadly acceptable loads. Analysis showed that performance is affected primarily by the exit angle, The minimum point in each curve represents its optimum, and it is clear with diminishing aircraft performance returns from increasing exit angle. that it differs for the nose and main gears. With the main gear identified as Figure 12 shows the trend of launch benefit ‘flattening off’ as the exit angle driving the ramp optimisation (see Fig. 15) – then it is from this optimum increases above the CVS datum. Figure 16. Elements of a ski-jump ramp profile. point that the detailed profile is derived. This flattening off is more severe than seen in legacy Harrier analysis, but exists due to the fundamental differences in the F-35Bs STOVL propulsion system. For the F-35B, with increasing ramp 6.5 Quartic profile exit angle, the nozzle vector angles and thrust split (between lift fan and core) required to trim the aircraft mean the propulsion system is not The use of a polynomial equation to represent the ramp profile is reflected operating at the point at which maximum total system thrust is generated, in that the transition is a cubic and the circular arc a quadratic. The use of a thus reducing the air path acceleration. At higher weights the acceleration single cubic or quartic equation to define a profile was mentioned previ- reduces below the minimum threshold, as shown in Fig. 13. Figure 12. Performance variation with ramp exit angle. ously as a method but, although unsuccessful in direct application, the This lower air path acceleration results in the initial post-exit increased effort did highlight the advantage that a curve to a quartic equation has a height rate benefit of higher exit angles being washed out to approximately smoother variation of curvature and offers the advantages of a less oscil- the same as lower exit angles by the end point of the analysis, as demon- latory load profile and a lower peak. A least squares fit method was used to strated in Fig. 14. convert the optimum cubic transition plus circular arc profile to a quartic This balance is indicative of the complexity of optimising the perfor- curve, and the variation of curvature is plotted in Fig. 18. mance, other factors including the need during the STO manoeuvre to This demonstrates the subtle change in curvature, and Fig. 19 shows the angle the core nozzle downwards slightly in order to offset the lift fan significant change in gear loads resulting. vertical thrust (since its aft angle is restricted) and ensure a minimum nose In addition to the slight reduction in peak gear loads, the load trace gear load for adequate steering. Figure 17. Gear Loads against ramp profile index. exhibits beneficial features with less oscillatory behaviour and a marked turndown towards the end of the ramp. The latter is of considerable value as it eliminates the new load peak being generated in the original profile. 6.2 Loads and exit angle decision The method used to generate the nominal profile was that of a cubic Note also that the nose gear sees a slight increase in both peak load and its Using the loads metric as an upper boundary achieves the most efficient transition into a circular arc, consisting of a fixed transition length and a oscillatory tendencies, although there is still a large margin available. ramp, as defined by imparting the maximum upward momentum without fixed radius of curvature, an approach common in engineering disciplines, exceeding the loads metric. A range of ski jump ramps were created using e.g. railway track transitions from straight sections into corners and aerody- the longer version of the CVS angled ramp as a template to design higher namic streamlining. Geometric relationships are used to match the 6.6 Lead in and let down angled ramps. Figure 15 shows the nose and main peak gear loads tangency at the end of the cubic transition curve with the start of the Figure 19 also shows the rapid load increase at the ramp entry and the lead generated. Figure 13. Air path acceleration against ramp exit angle. circular arc. Overall height and length are outputs and creating a ramp to in, in this case a rounded step. Assessment of different sized steps, as well From this it can be seen that the nose gear is well below the metric for all satisfy constraints in these requires iteration. The key advantage is that the as using much longer lead-ins was conducted with little or no difference angles, and that a maximum exists for the main gear. curvature can be controlled in two easily understood and modifiable noted. A decision was taken to use a similarly sized step as the CVS ramp The maximum exit angle dictated by the gear loads is 12·5 degrees, variables that relate directly to the profile and loads. on the grounds that this approximated the diameter of runway arrestor slightly greater than the CVS angle, and was selected as the ramp exit angle There are alternative ways of generating the nominal profile, described wires used for trampling analysis in the main SDD program and which for the following reasons: in the references, but the ‘cubic plus transition’ was deemed the most show similar acceptable loadings. ● The loads are at their maximum tolerable threshold as defined by the effective. Trials with other methods proved them to be significantly more The let down was designed as an ellipse, blending from the tangent at metrics. complex to use with no observable benefits. the end of the nominal profile to the horizontal, where it would interface ● The level of performance derived from this angle is comparable with The lead-in step intersects the nominal profile allowing the section prior with the proposed aerodynamic fairing that sits ahead of the ramp. the requirements. to this, which consists of negligible height (and thus of minimal benefit whilst also being difficult to manufacture) to be eliminated so the length ● CVS ramp performance capability is achieved, but with acceptable freed up can be used for a higher radius of curvature. The resulting load loads. spike at the step is within load limits and actually aids the overall process 7.0 CANDIDATE RAMP DEFINITION by rapidly increasing the load towards the steady maximum as in Fig. 6, The CVF candidate ramp was defined as a 12·5 degree angled ramp with which also reduces the peak of the overshoot on ramp entry, particularly 6.3 Ramp profile design the profile achieved by combining a nominal profile based on a quartic fit for the nose gear. to an optimum cubic transition plus circular arc, a rounded step lead in and Having identified a suitable exit angle, effort was then focussed on devel- The let down was added to previous ramps when it was discovered that an elliptic let down. Definitive performance and landing gear loads data oping a detailed profile. A ski jump ramp can be characterised as having the rapid unloading of the gear at ramp exit caused loading problems and were generated to demonstrate the resulting capability and compliance with Figure 14. Height rate against air speed for varied ramp exit angle. three distinct parts, as illustrated in Fig. 16. there was a requirement to provide a section of ramp that would restrain the the metrics. 8.0 OTHER RAMP DESIGN ISSUES In addition to the single event performance and loads analysis used to optimise the ramp profile, other aspects were considered for CVF ramp optimisation: ● Cyclical loading: fatigue impact was assessed and found to be significantly lower for the candidate ramp than a CVS ramp. ● Weapons physical clearance: to ensure that the carriage of bulky external stores (e.g. stand-off missiles or fuel tanks) does not result in parts of these breaching minimum clearance distances due to the curvature of the ramp. Worst case store loadings with combinations of fully flat tyres and compressed struts confirmed Figure 18. Variation of curvature against length for original cubic transition plus circular arc, and quartic fit. no clearance breaches.

8.1 Manufacturing The ramp profile must be transformed into a physical structure, and to do this build tolerances on the candidate profile are required. Figure 20 illustrates the elements of the ramp profile and the issues related to manufacturing. As discussed earlier, a margin was applied to the loads metrics in order to account for variations between the mathematical profile derived during the analysis and the ‘as-built’ structure. To ensure this margin was sufficient and to provide the ship builders with useful guidance regarding build tolerances, analysis was conducted on each of the elements and issues: Figure 19. Main and nose gear loads for original and quartic fit. ● Segment size: this is the discretisation of the ramp when speci- fying ordinates and represents the size of each flat plate that forms the curve. Increasing segment length raises the angle between each plate leading to load spikes. ● Co-ordinate accuracy; this represents the accuracy to which the theoretical curve is converted into a set of ‘design-to’ points at an accuracy level appropriate for manufacturing, with loads affected due to the change in angle between each point. ● Bumps and dips: These are variations from the ‘design-to’ profile when designed, fabricated, installed and subject to usage, which result in raised and/or sagged parts of the ramp. A modified DEFSTAN approach (Ref. 10), using bump/dip depth and length parameters based on legacy experience was utilised to produce a suitable build tolerance. Figure 20. Ramp profile, manufacturing elements and issues.

9.0 CONCLUSION The paper has covered all the principles and processes used in designing a candidate ski-jump ramp profile for the CVF, optimised for the F-35B. REFERENCES With loads metric eventually dictating the choice of exit angle and 1. FOZARD, J.W. Ski-Jump – A great leap for tactical airpower, British Aerospace the ramp profile shape, this demonstrates the importance of developing Paper, 1979. and defining the optimisation metrics.Compared to the CVS ramp, the 2. SPAVINS, C.S. Harrier – ski jump, RAE Bedford Paper, ~1981. candidate ramp offers comparable performance but with acceptable 3. THORBY, D.C., JOHNSON, J., AULD, A.B.K., NEWMAN, H.T. and BROOKER, M.J. loads. The special requirements of a VSTOL aircraft, British Aerospace, AGARD Paper October 1990. The key issues involved in converting a mathematical profile to a 4. JOHNSON, J. and THORBY, D.C. Sea Harrier: The design of a 6 degree ramp for physical structure have been explained. a 425ft flight deck, BAE Systems Internal Report: HSA-KSD-N-HAR-715, The team and customer are now taking this profile forward as part of April 1976. the continuing integration of the F-35B aircraft onto CVF. 5. AULD, A. A ski-jump ramp design for INS Vikrant, BAE Systems Internal Report: BAE-KSD-N_HAR-1042, October 1981. 6. THORBY, D.C. Landing gear for ASTOVL: A Discussion Paper, BAE Systems Internal Report: BAE-KAE-N-AST-4081 June 1993. ACKNOWLEDGMENTS 7. THORBY, D.C. STOVL Landing gear criteria and related topics, British Aerospace Internal Memorandum, 1999. Rob Chapman BAE Systems 8. ROSA, M. and ROLFE, R. Ski-Jump launch performance studies in Dstl, Dstl John Johnson BAE Systems IPLC08 Paper 06, July 2008. John Medzorian Lockheed Martin 9. NICHOLAS, O.P. An insight into optimal launch performance from a ski-jump, Tim Newman BAE Systems Dstl Report, October 2003. Martin Rosa Dstl 10. MoD DEFSTAN 00-970 Pt3, 1, (305), Design of undercarriages – operation Steve Solomon Lockheed Martin from surfaces other than smooth runways. UK MoD Publication, 1994.

NE-3, 07 APR 2011 to 05 MAY 2011 MAY 05 to 2011 APR 07 NE-3,

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NE-3, 07 APR 2011 to 05 MAY 2011 Field Activities > Patuxent River Naval Air Station, Maryland

The Naval Air Warfare Center Aircraft Division (NAWCAD), Patuxent River Maryland, is the Navy's research, development, test and evaluation (RDT&E), engineering and fleet support center for air platforms. Patuxent River is also home to the Naval Air Systems Command (NAVAIR). Ranges at Patuxent River include extensive inshore and offshore operating areas to support the full array of testing required for a new air platform. The airfield test facilities include a land based TC-7 catapult and MK-7 arresting gear and other unique test facilities geared toward the evaluation of weapon systems designed to operate in a shipboard environment.

NAWCAD provides approximately 220 Work Years (FY05) of critical engineering expertise to virtually every Integrated Product Team within the JSF program. Major efforts include the standup of facilities to support a total contractor and government F-35 test team of approximately 700 personnel. All Carrier and STOVL F-35 variant test airplanes will be developed at Patuxent River, totaling nine aircraft at peak. Unique F-35 tests to be conducted at Patuxent River include land based catapult and arrestments, STOVL vertical and short takeoff and landing tests, expeditionary airfield operations, the full range of aero- sciences envelope expansion, mission systems development and weapon certification testing.

The Lockheed Martin X-35C and the Boeing X-32B were both tested at Patuxent River during the JSF Concept Demonstration program. The X-35C is currently on display at the Patuxent River Naval Air Museum, and the X-32B will be prepared for display by March 2005.

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Home Facilities/Capabilities Aircraft Launch and Recovery / Support Equipment Centerfield Short Take Off/Vertical Landing (STOVL)

Centerfield Short Take Off/Vertical Landing (STOVL)

The Centerfield STOVL (Short Takeoff/Vertical Landing) was completed in 2009, to support the developmental testing of the Joint Strike Fighter (JSF) F-35B STOVL aircraft. Located in the centerfield area at NAS Patuxent River, the STOVL Centerfield Facility consists of an AM-2 Expeditionary Airfield (EAF), an AM-2 Vertical Takeoff and Landing (VTOL) pad within a painted LHD deck outline, a Ski Jump, and a grated Hover Pit.

The EAF and VTOL Pad AM-2 surfaces are representative of current US Marine Corps austere/forward deployed basing capabilities. These surfaces will be used to test F-35B compatibility during Short Takeoff (STO), Vertical Landing (VL), and Slow Landing (SL).

The Ski Jump, built to match the profile of the UK HMS Invincible Class Ships, will provide a land-based test site for unique ship compatibility. The Hover Pit was constructed during the X-32/X-35 concept demonstration phase of the JSF Program and has supported operations with British Sea Harrier aircraft.

The Hover Pit also provides a means to perform STOVL mode engine runs without ground effects by ducting exhaust thrust away from the aircraft through a series of vanes below the top grating of the pit.

Centerfield STOVL

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Title: The STOVL Joint Strike The Marine Corps does not have enough will replace it, is the only jet that deploys they have USMC painted on them. You Fighter in Support of the equipment to supply significant amounts of with USMC MEU’s as dedicated fixed-wing don’t have to worry about overfly rights or fuel and ammo to maneuver units. Relying aircraft that are “owned” by the MEU com- basing rights. We need to be able to rely 21st Century Marine Corps almost exclusively on aviation to supply for- mander. According to Brigadier General on ourselves and the Harrier is a compli- ward bases will place an enormous burden Blackman the Harrier makes the MAGTF mentary asset to the MAGTF.” Author: Major Ben D. Hancock, on already limited vertical lift capability. complete. “Harriers are another tool for VI. Conclusion United States Marine Corps (1997) Recommendations: The Navy-Marine Corps the MEU Commander, they don’t provide The potential basing flexibility and fire- team must develop and refine STOVL 24 hour capability under all conditions, but power that the STOVL Joint Strike Fighter Thesis: The potential basing flexibility and employment concepts that includes ramps they do bring additional capability and offers the Marine Corps in support of firepower that the Joint Strike Fighter (JSF) (ski jumps) and smaller EAFs and it must flexibility to the MEU.” Blackman contends OMFTS will not be realized with the current offers the Marine Corps in support of Op- fund the hardware and structural improve- that you cannot always count on the Car- doctrine and equipment that determines erational Manuever From the Sea (OMFTS) ments that allow STOVL aircraft to oper- rier Battle Group being there with fixed- how we operate and support STOVL jets will not be realized with the doctrine, mind- ate in their intended environment. If we wing support when you need them and it on amphibious ships and ashore in an set, and equipment that currently deter- envision maintaining a primarily sea-based may be overkill (may be perceived as too expeditionary environment. Although the mines how we operate and support STOVL approach to conducting operations and we threatening or offensive in delicate politi- JSF will to be able to perform all of the jets on amphibious ships and ashore in an require responsive day/night air support cal situations) for some scenarios. Colonel missions currently flown by both the AV-8B expeditionary environment. in all-weather conditions, then we need Richard F. Natonski, USMC, a recent com- and F/A-18 and do them better, the Marine Background: In the 21st Century the JSF to fundamentally change how we operate mander of the 24th MEU commented on Corps cannot just buy the aircraft without will replace both the F/A-18 and the AV-8B fixed-wing jets off amphibious ships. The the availability of the CVBG in support of also having the ability to support it prop- as the USMC fulfills its goal of an all-STOVL most significant contribution that the Navy the MEU: erly or to maximize its potential. aviation component. STOVL aircraft in- could make to STOVL air and helicopter- “We didn’t see the Enterprise It is clear that many of the cur- crease basing flexibility which is fundamen- borne power projection is adding a ramp CVBG for the entire deployment. We didn’t rent problems faced by STOVL aviation are tal to the expeditionary nature of the Ma- to all LHA/LHD class amphibious ships. A have any integration of the CVBG and the external to the aircraft. The Navy-Marine rine Corps and provides the foundation for dedicated “JSF carrier”, such as an LHA/ ARG/MEU. The CVBG spent 90 days in the Corps team must develop and refine STOVL improved responsiveness. OMFTS seeks LHD with a ramp and updated radars, Persian Gulf and during that time the only employment concepts that will optimize to avoid establishing a traditional logistics would serve as the optimum mobile for- fixed-wing air we had were our AV-8Bs and the basing flexibility of the JSF. Margin- base ashore and the majority of firepower, ward base. the aircraft landbased in Aviano, Italy. ally supported aboard amphibious ships to include aviation, will remain afloat and Although the most effective means General Blackman supports the and difficult to support ashore in a true only go ashore if necessary. This means of employing the JSF would be to base STOVL JSF, but only if it brings F/A-18 type forward based scenario, some of the AV- that the JSF will operate primarily from it ashore as soon as possible, it should performance and capability. “I think that 8B’s problems will be inherited by the JSF naval ships versus land bases. The JSF will remain sea based for as long as possible if you had the same survivability, reliabil- unless the Navy and Marine Corps provides be a far more capable aircraft than the AV- where it can be more easily provided with ity, and maintainability as the F-18 with all the necessary doctrine, equipment and 8B, but if the shipboard environment that fuel, ordnance, and maintenance without the same or better capabilities, and the commitment to eliminate or reduce these it operates in is one which remains margin- becoming a logistical burden. Seabasing jet was STOVL, then you have the best of problems. The Marine Corps believes in alized and biased against effective fixed- may remain the best means of enhancing both worlds.” STOVL fixed-wing tactical aircraft, we now wing operations, we will not fully realize sustainability and reducing vulnerability. Colonel Conry also supports the need a STOVL aircraft that performs as the JSF’s firepower and flexibility. all-STOVL aviation concept. He believes well as the F/A-18 or better. If the engi- Forward basing tactical aircraft STOVL Jet Value: With the acknowl- that it is part of our MAGTF ethos and that neers, designers and the Marine Corps are reduces the distance to the battlefield edged limitations and historical employ- we should stay committed to it. Colonel right, the STOVL Joint Strike Fighter will be and improves response times and aircraft ment of the Harrier in mind, we will now Conry is a big supporter of STOVL jets and that aircraft. surge rates. Operating jet aircraft from examine the value of STOVL jets to the says that “the real strengths of Harriers http://www.globalsecurity.org/mili- dispersed sites is a big logistical challenge. Marine Corps. The Harrier, and the JSF that are the flexibility that they bring and that tary/library/report/1997/Hancock.htm News Release: E200906291 EAF enables JSF landing anywhere, everywhere 29-Jun-09

PATUXENT NAVAL AIR STATION, Md. -- Marine Wing Support Squadron 274 gave engineers help in April to lay the first expeditionary landing site for the F-35B Lightning II Joint Strike Fighter for short takeoff/vertical landing (STOVL) capabilities testing.

Expeditionary Airfields are mobile systems that allow Marines to quickly build functioning airfields in areas without airfield support. EAFs are built using AM-2 matting: aluminum panels which are assembled in a brickwork pattern to form runways, taxiways, parking sites and other areas required for aircraft operations and maintenance.

These EAFs allow the JSF to perform missions in any terrain that does not support a standard-use airfield in mission - critical areas.

“This joint testing is a significant step for the Aircraft Launch and Recovery Equipment program,” said ALRE Program Manager Capt. Randy Mahr. “The JSF and EAF have an integral relationship in expanding our capabilities and success on the battlefield. The EAF’s AM-2 matting is battle tested, dependable and versatile. It’s exactly what we need for our expeditionary landing and take-off platforms.”

Although the AM-2 matting is serving its purpose as vertical take-off and landing (VTOL) pads and a 1,900 x 96-foot runway for the EAF/STOVL testing, it also doubles as the run-up for a test “ski-jump” used in conjunction with JSF testing for the British Royal Navy. The AM-2 matting and the 12-degree ski-jump ramp were installed at the centerfield area last month.

“NAVAIR is excited about our involvement in the JSF program, said Mike Jiavaras, ALRE’s EAF team leader. “Knowing that the first time this aircraft demonstrates its impressive VTOL capabilities will be on an expeditionary airfield raises the level of pride the team has in our program and in support of the warfighter.”

The ski-jump ramp is used by British Her Majesty’s Ship (HMS) Invincible-class carriers for launch of STOVL aircraft, such as the Harrier GR7A, and is located on the forward-end of the flight deck. JSF program experts explain that the ski-jump is a more fuel efficient way for aircraft take-off. However, the drawback is that it does not allow larger aircraft such as the E- 2D Advanced Hawkeye, F/A -18E/F Super Hornet and the EA -18G Growler - future carrier deck-mates with the JSF, the needed distance for launch and recovery.

The mock ski-jump is 150 -feet long, with a 15-foot high “lip” for aircraft launch. These shore-based ski-jump takeoffs will be conducted at varying airspeeds prior to the first UK ship detachment with the F-35B.

“We are extremely excited about getting the first of eight F-35’s to Patuxent River beginning this summer. The first aircraft to arrive, a STOVL aircraft designated BF-1, will use test facilities we have built to test and verify the unique warfighting capabilities the STOVL variant brings. We look forward to supporting the long-standing traditions of expeditionary warfare capabilities for the next 50 years of Marine Corps aviation,” said Capt. Wade Knudson, acting deputy program executive officer and program manager for F-35 Lightning II development. http://www.navair.navy.mil/press_releases/index.cfm?fuseaction=home.view&Press_release_id=4144&site_id=15

-- 30 -- . EAF 2000 Capabilities Expeditionary Airfield 2000 (EAF 2000)

• 3,850 ft runway & parallel taxiway Six Total EAF 2000s • Three sets of arresting gear • Three on MPF, 3 stored • Visual Landing Aid and Lighting Systems • Hot refueling pits EAF Training Sites • 78 parking spaces • 1st MAW - Ie Shima & VTOL Pads • 75 tactical aircraft (fixed and rotary wing) • 2nd MAW - MCALF Bogue & VTOL Pads • Three transport aircraft (KC-130) • 3rd MAW - 29 Palms, Red Beach, Aux II and others • Supports Joint operations • All naval TACAIR jets, transports, and assault support aircraft • C-17 capable Future Efforts Improved EAF Lighting High heat-resistant mat for supporting JSF

SAMPLE CONFIGURATION ROTARY WING PARKING HELO HOT REFUELING POINT DESIGN WILL BE DEPENDENT ON MISSION AND ACE SUPPORT TO THE MAGTF CARGO RAMP

RUNWAY ARM/DEARM PAD TAXIWAY

FIXED WING HOT FIXED WING REFUELING POINT PARKING APPROXIMATELY 1.6 MIL SQFT EAF enables JSF landing ary airfield raises the level of pride the team AM-2 matting was used in expediting airfield setting up crushing and batching plants in has in our program and in support of the construction by eliminating the time required South Vietnam took as long as five months. anywhere, everywhere warfighter.” for placing Portland cement or asphaltic AM-2 matting required only the equipment to Press Release: E200906291 29-Jun-09 The ski-jump ramp is used by British concrete pavement. AM-2 mats were 1.5- deliver the 2,000-pound pallets and could be inch thick aluminum alloy panels, 12-foot- laid entirely by hand. PATUXENT NAVAL AIR STATION, Md. -- Her Majesty’s Ship (HMS) Invincible-class by-2-foot, each weighing 144 lbs. Half mats, Aluminum matting provided a valu- Marine Wing Support Squadron 274 gave carriers for launch of STOVL aircraft, such 6-foot-by-2-foot, were also used. A nonskid able tool for the construction of airfields in engineers help in April to lay the first expe- as the Harrier GR7A, and is located on the ferrous coating was factory-applied to the forward or remote areas. In combat landing ditionary landing site for the F-35B Light- forward-end of the flight deck. JSF program wearing surface. Mats were fastened togeth- operations, matting made it possible to con- ning II Joint Strike Fighter for short takeoff/ experts explain that the ski-jump is a more er by interlocking connectors and secured struct jet airfields when and where construc- vertical landing (STOVL) capabilities testing. fuel efficient way for aircraft take-off. with locking bars. Mats could be laid on the tion would otherwise be impossible. AM-2 Expeditionary Airfields are mobile systems However, the drawback is that it does ground or a subsurface of soil-cement after matting is available today to make rapid that allow Marines to quickly build function- not allow larger aircraft such as the E-2D required grading and leveling. The life of the repairs of bomb-damaged runways. ing airfields in areas without airfield support. Advanced Hawkeye, F/A-18E/F Super Hor- surface could be extended by waterproofing Matting Installation EAFs are built using AM-2 matting: aluminum net and the EA-18G Growler - future car- the soil with a polyethylene membrane or The most effective method of laying panels which are assembled in a brickwork rier deck-mates with the JSF, the needed impregnated asphaltic material prior to lay- matting was to use four-man crews -- two pattern to form runways, taxiways, parking distance for launch and recovery. The mock ing the aluminum mats. The matting rested men to place the mat panels, one to place sites and other areas required for aircraft ski-jump is 150-feet long, with a 15-foot high directly on a two-ply nylon membrane which the locking bars and spacer bars, and one to operations and maintenance. These EAFs “lip” for aircraft launch. These shore-based was resistant to abrasion and JP-4 fuel. assist with a crowbar and mallet as needed. allow the JSF to perform missions in any ski-jump takeoffs will be conducted at vary- Panels were laid in a staggered brickwork The jobs were rotated among the crew terrain that does not support a standard-use ing airspeeds prior to the first UK ship de- configuration with the longer 12-inch dimen- during the shift to minimize fatigue. An ad- airfield in mission-critical areas. tachment with the F-35B. “We are extremely sion perpendicular to the main direction of ditional crew of approximately twenty South “This joint testing is a significant step excited about getting the first of eight F-35’s traffic. The system was designed for 1,600 Vietnamese laborers disassembled the AM-2 for the Aircraft Launch and Recovery Equip- to Patuxent River beginning this summer. passes of a 27,000-pound single wheel load bundles. Air Force personnel operated the ment program,” said ALRE Program Manager The first aircraft to arrive, a STOVL aircraft at 400 p.s.i. tire pressure (approximately the lowboys, forklifts and the cranes for mat- Capt. Randy Mahr. “The JSF and EAF have designated BF-1, will use test facilities we weight of an F-4B). ting resupply. Placement crews, backed up an integral relationship in expanding our ca- have built to test and verify the unique warf- AM-2 matting-surfaced areas of a by labor units, could lay over 500 linear feet pabilities and success on the battlefield. The ighting capabilities the STOVL variant brings. typical installation included a 102-foot-by- of runway (50,000 square feet) in a 9-hour EAF’s AM-2 matting is battle tested, depend- We look forward to supporting the long- 10,000-foot runway, a 48-foot-by-10,000-foot shift. able and versatile. It’s exactly what we need standing traditions of expeditionary warfare main taxiway, four 48-foot-by700-foot cross Because of the hot weather in South- for our expeditionary landing and take-off capabilities for the next 50 years of Marine taxiways, and a 570-foot-by-1,900-foot park- east Asia, matting teams often found their platforms.” Although the AM-2 matting is Corps aviation,” said Capt. Wade Knudson, ing apron totaling nearly 3 million square productivity on the runway limited to a few serving its purpose as vertical take-off and acting deputy program executive officer feet -- an amount sufficient to build a 2-foot hours during the day. Heat reflections from landing (VTOL) pads and a 1,900 x 96-foot and program manager for F-35 Lightning II wide footpath between San Francisco and the aluminum matting sent air temperatures runway for the EAF/STOVL testing, it also development. Los Angeles. soaring to 125°F making it nearly impos- doubles as the run-up for a test “ski-jump” http://www.navair.navy.mil/press_re- The use of aluminum matted offered sible to touch the even hotter AM-2 panels. used in conjunction with JSF testing for the leases/index.cfm?fuseaction=home. many advantages over Portland cement and Night work, therefore, was the answer, and British Royal Navy. The AM-2 matting and view&Press_release_id=4144&site_id=15 asphaltic concrete. It eliminated the need although heat was still a factor, the men the 12-degree ski-jump ramp were installed for concrete aggregate (which often was could operate effectively for longer periods. at the centerfield area last month. “NAVAIR not readily available to combat airfield sites) Work on operational runways was also ac- is excited about our involvement in the JSF AM-2 MATTING as well as the equipment, work, and time complished at night to avoid interfering with program, said Mike Jiavaras, ALRE’s EAF AM-2 aluminum matting, an evolution of the required to crush the aggregate, prepare the the flying mission. team leader. “Knowing that the first time pierced steel planking used in World War mix, dig foundations, install forms, and place this aircraft demonstrates its impressive II, was adopted by the Air Force in 1965 http://www.nationalmuseum.af.mil/ the concrete. Procuring, delivering, and VTOL capabilities will be on an expedition- for use in nearly all bases in South Vietnam. factsheets/factsheet.asp?id=1270 Battlelab designed and executed an initia tive in FY04 to evaluate some of the most 3BNQJOH
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In this imminent start of shipboard trials were regularly “in the mid-90s and mode, the stick commands upward/ with the F-35B Joint Strike Fighter, pressures varied between 29.6 and downward vertical velocity with a test pilots have given high marks to 30.4 inches [of mercury),” he adds. backward-forward motion, while in the jet’s vertical-landing handling Testing has involved qualifying the hover mode sideways move- characteristics, though they cau- seven pilots, two of whom have ment of the stick commands bank tion that more work is needed to now retired, including Jon Beesley, angle. If released, it returns the mitigate the effects of hot gas the first Lockheed Martin F-35B aircraft to wings level. Pedals com- re­ingestion. chief test pilot. Beesley’s flight in mand yaw rate in the hover. Test results from ongoing F-35B the second F-35B, BF-2, on Jan. 19 The fastest descent rate, as con- short takeoff-and-vertical-Ianding marked the first vertical landing trolled by pushing the stick forward, (Stovl) evaluation at NAS Patuxent achieved by a non-Harrier-trained is set at 7 fps., though the testing River, Md., have “been phenomenal,” pilot. In addition, at least one other has included rates as low as 4 fps. says Pete Wilson, BAE Systems lead pilot in the initial cadre did not have and high as 12 fps. pilot for the Stovl test program. The legacy Harrier experience. However Testing has also focused on the pace of testing and quality of results Wilson says ab initio conversion translational rate command (TRC) marks a dramatic turnaround from training for hovering and vertical- mode, which in the hover allows just over a year ago, when issues landing qualification took as little as the pilot to make small positional with unexpected wear on auxiliary half a day, compared to “at least” corrections and which brings the inlet door hinges brought vertical- three times that for the Harrier. aircraft to a standstill if the pilot landing tests to a halt. Speaking at the Society of releases the controls. “It is used The test team is now “close to Experimental Test Pilots symposium to capture the current longitudinal groundspeed and is important for “We’ve been recording the points indicated the worst-case conditions precise positioning in shipboard on the pad where the nozzle is would be found “at around the operations,” says Wilson. pointed and, after initial landings, height of a two-story house, and On the Cooper-Harper rating removed the specific tile and tested we have found a close match to scale used by test pilots to evalu- it for strength. There was no loss of predictions,” Wilson says. Testing ate handling characteristics, pilots strength,” Wilson says. “Now we’re of the HGI effects and how to gave an average rating of 1.77 for waiting for 10 vertical landings mitigate them will be the focus for descent and 2.28 for landing in on one specific tile before we do future work. “We’ll be doing more baseline vertical-landing mode. For the next strength test.” As of late of that as we continue investigating the TRC mode, pilots rated descent September, fewer than half of the HGI,” says Wilson. at 1.52 and landing at 2.04. The required number of landings on the HGI, which may ultimately be scale ranges from 1 to 9, with 1 particular tile had occurred. Overall, handled with software changes, is representing excellent characteris- results of the testing to date “give not an issue for the shipboard tests, tics and a low workload task and 9 no cause for concern for AM-2 according to Wilson. “We wouldn’t representing major deficiencies and compatibility,” Wilson says. be going to the ship if we were not intense pilot compensation required Additionally, ground personnel comfortable with our compatibility,” to maintain control. have gradually moved closer to he says. Tasks also included evaluations the pad for each vertical landing, In the run-up to tests on the of two areas of potential concern as part of systematic efforts to amphibious landing ship USS Wasp, to F-35B shipboard operations: determine the safest proximity to due to begin this week, the focus measurement of the impact of the the touchdown area. Wilson says has been preparing the test pilots hot exhaust on the landing pad that so far these tests indicate safe and ground crews with dry-runs and deck environment, and hot gas distances similar to those of current in which aircraft are brought to a ingestion into the inlet. Vertical Harrier operations. low·level hover above the pad to landings at Pax River have been The challenge of hot gas inges- simulate shipboard approaches. conducted on two pads made from tion (HGI) also remains a key test “We’re ready to go,” says Wilson. standard extruded AM-2 aluminum focus. Performance in the hover tile mats measuring 120 ft. and suffers due to HGI, which reduces Aviation Week & Space Technology; 150 ft. square, respectively. engine thrust. Pretest modeling October 3, 2011; pages 31-32

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Acquisition of Capabilities through Systems-of-systems: the aircraft carrier and military aircraft have evolved both independently and together in the face of, and in response to, changing military needs. The success of their Case Studies and Lessons from Naval Aviation evolutionary ability means that they are still seen as providing important capabilities for the long term. Presenter: Dr. Michael Pryce is a Research Associate at Manchester Business School, currently working on a project entitled Network Enabled Capabilities Through Innovative Aircraft and aircraft carriers form symbiotic system for the delivery of capability. A Systems Engineering (NECTISE). He completed his PhD in 2008, which looked at the role of view of aircraft carriers as mere infrastructure, a floating runway and hangar for the design in the acquisition of STOVL combat aircraft. He also holds a Master’s degree in the aircraft it carries, misses much of its importance. In order to understand how to acquire history of technology and a Bachelor’s degree in history. He has worked as a process such capabilities, we need to understand the interactions between the aircraft carrier and engineer for GM and in web development. its aircraft. In this paper, the prosaic issues that matter in operating aircraft from ships Dr Michael Pryce will be illustrated. This is not to diminish the modern need for digital interoperability, etc., Centre for Research in the Management of Projects but rather to illustrate how matters such as simply being able to move aircraft around the Manchester Business School deck and hangar of a ship in an effective manner can have significant effects on Booth Street East, Manchester, M15 6PB capability. United Kingdom Telephone Work: +44 (0)161 306 3521 This paper examines the issue from the perspective of the United Kingdom’s Home: +44 (0)1273 227 046 E-mail: [email protected] Royal Navy and its experiences of deploying Short Take Off and Vertical Landing (STOVL) aircraft onboard its carrier fleet over several decades. Current acquisition policy in the UK is concerned with delivering capability using Through Life Capability Abstract Management (TLCM). This is defined as, “translating the requirements of Defence policy into an approved programme that delivers the required capabilities, through-life, across The acquisition community in many nations faces novel challenges with the all Defence Lines of Development” (MoD, 2009). transition to systems-of-systems, capabilities-based solutions to meet military requirements. Much of the “tribal knowledge” and experience of those in acquisition, The Defence Lines of Development (DLODs) allow for the co-ordination of the both in industry and government, has stemmed from platform-centred development development of the different aspects of capability that are needed to create a real strategies. It is questionable to what extent lessons from these can be applied to military capability. These aspects are: systems-of-systems acquisition. How does the acquisition expert trade off platform capabilities against the capabilities of a network of systems that might be composed of Training new and existing platforms used in new or old ways? Equipment This paper presents case studies from past and present, illustrating such issues, Personnel and seeks to draw out lessons from experience that may be useful. It draws on many years of empirical research, undertaken with those involved in addressing such issues in Information the acquisition community. Concepts & Doctrine Organisation Introduction Infrastructure Much work in the acquisition community, in many nations, has been undertaken Logistics in recent years toward achieving enhanced military capabilities through the use of systems-of-systems, network-centric or -enabled capabilities and through life It is only by addressing all the lines of development that the acquisition (and management of these. This work has been motivated by many different factors— sustainment) community can effectively deliver capability to the UK armed forces, evolving threats and military doctrines, changes in technology, force re-structuring, etc. through the various force elements (ships, aircraft, army units, etc.), which are then used Central to these efforts has been a desire to achieve interoperability of forces, allowing to create Joint Capability Packages. These are tailored by a force commander to the deployment of capabilities that, hopefully, are more than the sum of their parts. undertake particular missions or tasks, taking into account coalition forces, threats and the overall operating environment. This is shown in Figure 1. While much of this work has rightly focussed on the opportunities offered by new, notably digital, technologies, more prosaic (perhaps what could be seen as “old- fashioned”) issues also have a significant impact. Capability depends on the interaction of all system components and their differing characteristics. In this paper, the effects of = capabilities of such prosaic issues will be explored, with the focus on one of the oldest ======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 63 - “systems-of-systems,” the aircraft carrier and its aircraft. In a near century of evolution, =

======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 61 - ======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 62 - = = account for the higher overall equipment costs while the difference in costs attributable to doctrine is perhaps the most marked, reflecting the greater flexibility of the STOVL aircraft carrier and its aircraft.

While STOVL aircraft may be “easier” to integrate at one level with a ship (with no catapult or arrestor wires and the ability for STOVL aircraft to operate from smaller ships), what this example really illustrates is that the costs are distributed differently for a given capability depending on the nature of the systems used to deliver it. In the case of aircraft carriers and their aircraft, it is important to note that both are complex systems in their own right, with differing design, testing, manufacturing and support approaches. As Andrews (2003) has rightly pointed out, a ship does not have a prototype, unlike aircraft, and therefore, there is a need for the designer to ensure that it is “right first time.” However, in the case of an aircraft carrier, it is only once it is operating aircraft, or when a new generation of aircraft are introduced, that it can be determined if the design was indeed right—and that while it may be right first time, it may not be right second time, Figure 1. The Role of the UK Defence Lines of Development with new aircraft onboard. in the Creation of Capability The DLODS can therefore be seen as being the primary constituents of capability For the acquisition community, the issues attendant on developing and and forms a useful analytical tool to understand the impact of differing ways of delivering sustaining capability using ships and aircraft in combination present formidable capability. In this paper, we are concerned with the UK Royal Navy’s use of STOVL challenges. While traditional approaches to designing them separately may be seen as aircraft from its carriers. An illustration of how the choice of STOVL aircraft can impact less than ideal, the rest of this paper will explore how the acquisition process of the past on the DLODs is shown in Figure 2. has managed to achieve a large measure of success in doing this, despite being focussed largely around projects rather than overall capability.

Harrier and Invincible Class Experience and Design

One of the main “transformational” military technologies of the twentieth century was the development of aircraft to provide a new dimension to warfare. The impact of aircraft on naval warfare became apparent during World War II, notably in the great battles of the Pacific War, with Japan and the United States relying on aircraft and aircraft carriers as the centrepiece of their fleets. Post-1945, the aircraft carrier continued in this central role in major navies, and helicopters allowed the provision of air power to be extended to smaller vessels and lesser navies.

In the United Kingdom, attempts to sustain a viable force of major aircraft carriers foundered due to budgetary restrictions. Nevertheless, in order to retain a viable naval force, it was recognised (despite considerable inter-service debate) that some form of organic air power was still required to deliver the Royal Navy’s key NATO role of anti- submarine warfare in the Eastern Atlantic. This was a highly complex environment with threats from Soviet submarines, surface combatants and aircraft (both land- and ship- based) requiring a mix of capabilities to be able to respond to them. Figure 2. Comparison of UK and US Naval Strike Fighter Costs across the In order to meet these threats, the Royal Navy was largely forced to adapt the UK Defence Lines of Development land-based Harrier STOVL strike aircraft to meet their needs. The ability of the Harrier to (Stanford, 2008) land on many types of ship had been demonstrated since 1963, from full-size aircraft This figure illustrates how, for the achievement of a given capability, the costs are carriers to the helicopter decks of cruisers. The adoption of the Harrier by the US Marine allocated for the two examples across the DLODs, due both to the innate differences Corps during the 1970s had led to the regular use of the aircraft from the assault ships of between two different types of aircraft and also to the differing operational employment the US Navy, although only those (LPH and LPD) with full flight decks and hangars had of STOVL and CTOL aircraft. The UK STOVL aircraft training costs are lower than for Harriers based on them. = the US aircraft, attributable to the needs of “cat and trap” landings at 140 knots on the ======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 64 - US Navy supercarrier. However, the lower warload of the UK STOVL aircraft may = The Royal Navy was already planning a fore of anti-submarine warfare (ASW) The first installation of the “ski jump” on a ship was on the old light fleet carrier cruisers during the early 1970s, to operate helicopters only. However, the need for the HMS Hermes, which was given a 12-degree ramp during a refit and took Sea Harriers ships to carry more than six helicopters to meet the submarine threat from the Soviet onboard for trials in 1979. These trials showed that the concept would work at sea, Union led to the adoption of a “through deck” layout for the ships, essentially a miniature although it had already been decided to add ramps to the Invincible class during build— aircraft carrier, and in many ways the same basic layout as the US Navy’s assault ships although on the first two ships of the class, the ramp was at the lower angle of 7 from which the Harrier was already operating. The recognition of the inability of surface- degrees. This was due to the ships being fitted with a substantial anti-aircraft missile to-air missiles to fully meet the threat of “shadowing” reconnaissance aircraft of the launcher in the bows, the firing arc of which required the lower-angle ramp. This reduced Soviet Navy (providing targeting data for submarine launched anti-ship missiles) led the the benefits of the ramp, but still allowed a useful addition in payload or reduction in Royal Navy to push for the adoption of the Harrier to operate from the new class of ASW take-off run for the Sea Harrier (Brown & Moore, 2003). cruisers, with a small number of the aircraft operating alongside the helicopters. This led to the development of the British Aerospace (BAe) Sea Harrier, which first flew in 1978 Once HMS Invincible had been commissioned and began operating Sea (Brown & Moore, 2003). Harriers, it became clear that the two systems had not been designed for each other. The dimensions of the ships’ hangar had been defined by two main constraints—the However, the design of the ships, which became known as the Invincible class, need to change the rotor head of the Sea King helicopter and by the need for the ship’s was largely fixed before the decision to develop the Sea Harrier—HMS Invincible was own gas turbine propulsion system uptakes to pass next to the hangar. This produced a laid down in 1973, while the Sea Harrier was not funded for development until 1978. This “dumbbell” shaped hangar that was wider at its ends than in the middle section. While meant that, with the Sea Harrier being an adaptation of the land-based Harrier, neither this was adequate for the Sea King, the absence of wing folding on the Sea Harrier did the ship nor the aircraft was designed specifically for the other. For the ship, the hangar, mean that they were already approaching the limits of the hangar width in this area. flight deck, maintenance and stores (fuel, weapons, spares) facilities were all designed Even greater strains were caused by the Sea Harrier’s support onboard the ship, with around the Sea King ASW helicopter. They were also designed “to have the ability to perhaps three times as much fuel, spares, etc., required for each Sea Harrier than for take future VSTOL” (i.e., STOVL) aircraft, with provision made for STOVL aircraft (in each Sea King helicopter. In addition, the need to remove the wing of the Sea Harrier in terms of some additional space being allocated and with the aircraft lifts) sized for order to change its engine meant that a specialised hoist was installed in the hangar, STOVL aircraft. This latter assumed a generation of aircraft in advance of the Harrier, with an engine change requiring the aircraft to be trestled and secured to the hangar although it led to the assumption that such an aircraft would have similar dimensions to floor. The entire engine change evolution could take several days, monopolising a major an earlier STOVL project, which had been cancelled while still under development in part of the hangar and reducing the scope for aircraft movements in the hangar 1965: the Hawker Siddeley P.1154. The latter had been essentially a larger, faster, more (Andrews, 2009, February 12; Davies & Thornborough, 1996). powerful version of the Harrier concept (Andrews, 2009, February 12). While these limitations were coming to light, there were benefits to using the Sea Adapting the Harrier for use in a maritime environment proved relatively Harrier onboard the Invincible class. It quickly became apparent that the vectored thrust straightforward, with new avionics and minor systems improvements in addition to a engine of the Sea Harrier allowed it to “back taxi” under its own power, reducing the more noticeable new front fuselage. As the aircraft was relatively small, major requirement for tractors and towing gear and considerably speeding up the process of modifications such as wing folding were not required, although the radome folded for moving aircraft to and from parking areas on deck. This meant that landing and take-off maintenance access and to reduce the spotting factor. Tie-down lugs were added to the cycles could be increased, adding to the other benefits of operating STOVL aircraft such aircraft’s undercarriage to secure it to the deck, but, all told, “navalisation” added only an as the ability to dispense with “go around” fuel margins, reduced weather minima and extra 100 pounds of weight. This low figure was largely attributable to the ability of the high sortie generation rates. Sea Harrier to land vertically, so eliminating the need for strengthening to cope with arrested landings, as well as the aircraft’s ability to take-off without the need for All these aspects were proven of value during the Falklands conflict in 1982, in catapulting, with similar structural “beefing up” obviated (Fozard, 1978). which the Sea Harrier and Invincible class both proved their worth in a real conflict (Davies & Thornborough, 1996). Subsequently, both were updated, with the Sea Harrier In place of the catapult, one innovation allowed the Sea Harrier to operate at receiving a new weapons system, and the Invincible class adapted with additional higher weights from aircraft carriers. This was the “ski jump” ramp, an upwardly curved weapons and the ablity to operate a larger number of Sea Harriers (and later land-based addition to the end of the flight deck runway that enabled the Sea Harrier to take-off at Harriers). The anti-aircraft missile system was removed from the ships, allowing an either lower airspeeds or at higher weights for a given deck run than a “flat deck” take- increase in deck area and larger weapons magazines for the aircraft, and further off. The ramp also offered safety benefits, as it meant that the Sea Harrier should almost operational experience has proven that these adaptations have been valuable. always be launched on an upwards trajectory even if the bows of the ship were pointing down, as often happened in heavy seas. Trials on land during the latter half of the 1970s proved the concept of the ramp, and showed that only relatively trivial modifications to the Sea Harrier’s undercarriage were required to allow it to use the new “ski jump” technique (Fozard, 1978; Davies & Thornborough, 1996). ======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 66 - =

======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 65 - = As part of the threat analysis and operational research into how to meet such a threat, work in the UK Ministry of Defence (MoD) into the characteristics of a Sea Harrier replacement showed that supersonic speed would be a valuable asset. In meeting a notional attack from Soviet forces, it was seen that a smaller number of supersonic aircraft could cover the threat than was the case with subsonic aircraft using similar sensors and weapons. For some threats, only supersonic speed in the aircraft could provide an adequate response. This issue of aircraft numbers was important as the relatively small size of the Invincible class (plus the ships’ need to also accommodate anti-submarine helicopters) meant that the total number of aircraft carried was unlikely to exceed the number of Sea Harriers the ships could accommodate, about 8 STOVL aircraft (Pryce, 2008).

In industrial studies to develop a Sea Harrier successor aircraft (involving British Aerospace and Rolls Royce), the need to provide supersonic speed led to a number of design issues becoming the focus of much work. The most significant of these was that a much more powerful and energetic engine would be needed than that used in the Sea Harrier. This provided a number of environmental difficulties when operating aircraft onboard ships—as the noise, jet temperatures and velocities could adversely impact the deck environment of the ship as well as the aircraft itself to a significant extent (Pryce, 2008). One result of the work was that it was seen that it may be possible that when supersonic STOVL aircraft were hovering in advance of landing, the deck crew might need to use some form of refuge or shelter as the noise level could induce nausea and possible unconsciousness, and the high velocity jets of the aircraft could readily blow crew members overboard (Brooklands Museum Archive File HSA/SHR/047). Clearly, this would be unacceptable, as the role of the deck crew was to enable aircraft Figure 3. Royal Navy Sea Harriers Operating from an Aircraft Carrier operations (see Figure 3). during the Falklands War *Note the proximity of the deck crews, a problem in later studies for a Sea Harrier successor. (Harrier.org.uk, 2009) The effort to obviate such potential risks in the design stage led to a number of propulsion systems and operating techniques that sought to reduce such adverse effects However, it can be seen from this brief and incomplete history that designing the (Pryce, 2008). However, these brought with them a range of operational drawbacks as ships and the aircraft as separate projects—only loosely associated during well—such as the loss of the ability to “back taxi” and the introduction of engines that development—came at a considerable price in terms of reduced efficiency and were too large for the engine maintenance and storage spaces of the Invincible class. A difficulties in operation. These were offset by the personnel of the Royal Navy and Fleet visit by the aircraft design team from BAe to an Invincible class ship revealed further Air Arm who proved adept at coping with these difficulties. However, the costs of the complications that had not been assumed in their design studies, such as ruts in the equipment line of development were considerable, and adding costs in terms of hangar deck that could mean that if the nose undercarriage of some designs went into personnel, training and additions to the equipment to overcome deficiencies identified such a rut, the tail of the aircraft could “scrape” the hangar roof—despite the ruts only during use was undesirable, as was the in-built high logistics cost of the difficult nature of being an inch or so deep. In addition, it was realised that the highly integrated avionics some Sea Harrier maintenance operations and the confined spaces of the Invincible proposed for some of the new aircraft would require a complete re-arrangement of both class hangar. the maintenance spaces of the ship and the trade structure of the maintenance personnel (Brooklands Museum Archive File HSA/SHR/047). Sea Harrier Replacement Design and Invincible Class While these issues were not faced by all the new aircraft designs proposed (and With the experience of the Falklands War and the emergence of new threats for many of them managed to successfully address the existing problems with the Sea the Soviet Union (notably the deployment of Soviet aircraft carriers, fighters and long- Harrier, such as the difficult engine change evolution), it was apparent that the need for range maritime strike aircraft), meant that by the early 1980s, the Royal Navy was supersonic speed and the innate limitations of the Invincible class would cause actively pursuing a Sea Harrier replacement programme, in addition to updating the problems. In the aircraft design studies, it was to be assumed that the ships were not to earlier aircraft. One basic assumption was that such an aircraft would be in service be modified with special devices such as deck blast deflectors to accommodate the new during the lifetime of the Invincible class, so it had to be compatible with those ships. aircraft. It was discovered that a key limitation was the strength of the ski jump ramp of This allowed the opportunity to design new aircraft with the issues of operating from the the ships, as the new aircraft were much heavier, and that strength limitations of the Invincible class in mind, rather than evolving the aircraft design separately from the ship. ramp, as well as in the undercarriage of the aircraft, meant that in some cases the

======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 67 - ======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 68 - = = aircraft could not take-off with a full load of fuel or weapons (National Archive File AVIA Once these ship-dependent aspects of replacing the Sea Harrier were looked 6/25876). into, it became clear that being able to design a new aircraft “around” the Invincible class as it already existed was extremely difficult—as the change in the threat that the new While the aircraft designers were wrestling with these difficulties, additional aircraft were intended to meet meant that the aircraft had features that the Invincible analytical studies in the MoD and in BAe showed that further ship/aircraft interaction- class found difficult to accommodate. Attempting to trade-off aircraft performance levels dependent characteristics also provided limitations. With only a relatively small number against the deck environment and “traffic” issues on deck also proved extremely difficult, of aircraft carried by the Invincible class, high levels of availability were essential to meet and once wider issues such as the higher fuel/weapon loads of the new aircraft (leading the threats assumed. While the aircraft could possibly be more reliable than the Sea to more frequent replenishment operations) were considered, the work led to the Harrier, it became clear from assessment work of the deck and hangar movements of somewhat startling realisation that a new, “better” aircraft could lead to a reduction in the aircraft onboard the ship that critical limitations on availability were imposed on all capability compared to the Sea Harrier if it had to operate from an Invincible class ship aircraft designs, with reductions in the number of aircraft actually available for operations (Brooklands Museum Archive File BAe/PRJ/065—NST.6464). disproportionately affected by these limitations (Pryce, 2008; Brooklands Museum Archive File HSA/SHR/047). Harrier/Invincible Experience and CVF/JSF

For example, the ability of the Sea Harrier to “back taxi” under its own power Although the attempts at developing a replacement for the Sea Harrier foundered meant that it was able to move quickly into deck parking spaces. However, the during the 1980s, the Royal Navy eventually transitioned to a force of Harrier aircraft configuration of the propulsion systems of the some of the proposed successor aircraft operated in conjunction with the Royal Air Force in what is known as Joint Force Harrier. meant that this was not possible, so they would need to be towed around on deck. While With heavy commitments to operations in Afghanistan, there has been only limited a slower process in itself, the realisation that the turning circle of an aircraft plus tow bar opportunity in recent years to deploy these aircraft aboard the two Invincible class ships and tractor may be much larger than a Sea Harrier meant that not only were still in service, but it is the intention of the Royal Navy to replace these vessels in the manoeuvres slower, but also required greater free deck area to be carried out. Such free next decade with two much larger ships, under the CVF programme. area may not be available as the deck was already congested—with many areas used for more than one purpose (see Figure 4), and a “traffic jam” situation would result. These vessels are intended to employ the Joint Strike Fighter (JSF), in particular Similar problems arose when the size of the aircraft designs reached a point at which the the STOVL F-35B Lightning II version of the JSF. They will, therefore, be able to build size limits of the lifts or hangar were approached—narrow margins meant much more upon the experience of STOVL operations at sea built up over many years by the Royal careful positioning was required, which the crew were likely to have to do much more Navy, while at the same time benefitting from being able to design both systems in slowly. It was realised that while crew training and possibly increase personnel numbers parallel in order to maximise the capabilities they can provide. may make it possible ways to ameliorate such matters, it was difficult to accommodate additional crew onboard the ship and impossible to show the extent of training required One clear lesson that has been adopted on the CVF programme is that a large to ensure high levels of availability (Pryce, 2008; Brooklands Museum Archive File ship is helpful in operating even STOVL aircraft, as it gives much more space for moving HSA/SHR/047). aircraft around, which has been a problem in past operations and studies. Based on the idea that “air is free and steel is cheap,” this appears to be a welcome move, albeit one that may seem to reduce the need for using STOVL aircraft at all. Indeed, the CVF design has been developed so that it can be adapted for the later adoption of CTOL aircraft, including the CTOL version of the JSF. However, this would require not only a significant shift in UK procurement policy but also a re-assessment of all the lines of development for the CVF and JSF. As Figure 2 showed, the costs are distributed differently for the different types of aircraft, although basing them on versions of the JSF should reduce such differences.

Nevertheless, the current plan to deploy STOVL aircraft on the CVF means that the experience built up on the Harrier will be of use. This does not just depend on the service use of the Harrier, but also on research programmes that have used the aircraft. Most notable among these is the VAAC Harrier programme, which has been used to develop the flight control aspects of the STOVL JSF. In the Harrier family, the control of the aircraft was difficult because the pilot had a high work load when hovering the Figure 4. Invincible Class Deck Layout and Uses aircraft. For the JSF, the intention is that this can be reduced significantly, requiring much less training and greater flight safety, at the cost of a more complex flight control (The colours show the different uses of the deck, and how these uses could overlap. An system. aircraft landing on the deck could slow down take-off operations if it was unable to clear the landing area or to park quickly (Brooklands Museum Archive File HSA/SHR/047).) ======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 70 - ======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 69 - = Tests with the VAAC Harrier have revealed that the control system that came to extremely difficult, and probably undesirable, to tailor aircraft and ship designs to each be preferred from land-based trials needed some modifications when applied at sea other. This is because the lifecycles of each differ, and it may mean that they are then (Denham, Krumenacker, D’Mello & Lewis, 2002). In addition, the VAAC Harrier has been unable to contribute effectively to capability delivery when operated apart. used to develop the proposed Shipboard Rolling Vertical Landing (SRVL) technique that will allow the JSF to land at low speeds on the CVF, significantly increasing the “bring It is this difficult issue of optimising platforms as part of a flexible system that back” payload while reducing engine “wear and tear” (Rosa, 2008). While this should confronts acquisition managers. While it may be possible to use standards and protocols allow savings in terms of reduced maintenance as well as operations of the aircraft at to ensure interoperability of digital systems or of weapon pylon attachments and other higher weights and the deliverance of greater capability, there may be issues to address “lesser” mechanically based systems, at the level of complex, independent systems such that may offset these savings in other lines of development, such as training for pilots as STOVL aircraft and aircraft carriers, it becomes a matter of having (at some point) to and deck crew, and the development of additional deck lighting patterns and deck abandon the quest for an analytical “optimum” solution and instead to use judgement to parking arrangements (Hodge & Wilson, 2008). decide on the best mix of platform characteristics and interactions to deliver capability. It is then up to the skills and bravery of service personnel to adapt the platforms, and to Further benefits from previous experience with the Harrier, and studies into adapt to using them, in order to deliver a truly flexible range of capabilities using the replacing it, are shown by the adoption of a “ski jump” ramp for take-off. Despite the fact systems they are given. that the CVF is much larger than the Invincible class and that the JSF has a completely different propulsion system, the ramp still gives the same benefits as it did on earlier In order to support those involved in acquisition that need to use such judgement, ships: boosting capability by increasing payloads and enhancing safety, as well as as well to reduce the burden on service personnel later on, we will end with an outline freeing up more deck area for aircraft parking and recovery (Fry, 2008; Rolfe, 2008). suggestion for further research that may prove fruitful. Based on the researcher’s own This is also assisted by the use of a jet blast deflector, the value of which was first past efforts, and on discussions with practitioners in the field of aircraft and ship design, indicated in the Sea Harrier replacement studies. Again, despite the larger size of CVF, the researcher would suggest that attempts at understanding the real processes of the area of deck that it frees up for other uses is of great value, as is the enhancement of designing ships and aircraft, understanding how design is done and not just assuming the safety of deck crew by reducing the chances of them being blown overboard that it is done “by the book,” offers a route to providing a basis for sound judgement. (Morrison, Dockton & Underhill, 2008). Design is a multi-faceted activity: but from an acquisition perspective, it would appear that understanding the early conceptual, or project design, stage matters most. This is It is possible that the first aircraft to operate from the CVF will be those of Joint because many of the irrevocable decisions about a platform or system are made at this Force Harrier, as the ships may undertake trials (or be in operation) before the UK’s JSF stage, while trade-offs can be made against other platforms and systems—in an attempt fleet is ready to come aboard. If so, the experience of decades of Harrier operation will to achieve desired capabilities—relatively cheaply in terms of actual expenditures. be able to be directly applied to the new ships, while new lessons about the greater capability of the larger ship could be directly related to the experience of using the However, doing this in isolation would miss important lessons, and it would Harrier onboard the Invincible class. In addition, such an opportunity could allow appear that learning how to link current use of existing systems to the design of future validation of some of the Harrier-based research work that has helped to underpin the ones would be useful too. If we can see how the assumptions and decisions of JSF development. Although the equipment line of development subsumes many aspects yesterday’s acquisition experts have come to be used by today’s service personnel, of such research and technology programmes, there is little doubt that this work has perhaps we can learn how to anticipate a little better the needs of the future. Hopefully provided a significant contribution to reducing costs across the lines of development. this paper has made some small contribution to just such an endeavour.

Overview, Conclusions and Further Work Acknowledgements This paper has provided a limited view of the vast subject of operating STOVL The author would like to thank Professor David Andrews at University College, London, aircraft from ships. Its aim has been to illustrate how the experiences of the “prosaic” for giving up much of his time to help with talk about his experience of working on the Invincible issues covered matter in delivering capability, and how this capability is a product of the Class. Chris Farara at Brooklands Museum allowed generous access to material there, while the effect of these issues across the Defence Lines of Development. staff at the UK National Archive was helpful in locating much material on the early Sea Harrier replacement studies. In summary, it is hoped that this paper has shown that aircraft and aircraft carriers may benefit from being designed with each other in mind, but that they need to References adapt to changing operational, technical and other circumstances (budgetary!). The timescale for designing, building and operating aircraft and ships extends over many Andrews, D. (2003, September). A creative approach to ship architecture, RINA International decades, so it is simply not possible to design to a single “point.” Flexibility is an Journal of Maritime Technology. important attribute of both STOVL aircraft and aircraft carriers, with both able to Andrews, D. (2009, February 12). [E-mail correspondence with researcher.] contribute to capabilities independently of each other, but the flexibility of the combined Brooklands Museum Archive File BAe/PRJ/065—NST.6464 Project Papers—Operational system-of-systems that they deliver when brought together depends on an understanding of how the system functions over time. A key aspect of this is that it is Brooklands Museum Archive File HSA/SHR/047—Carrier Borne Air Operations

======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 71 - ======aÉÑÉåëÉ=^Åèìáëáíáçå=áå=qê~åëáíáçå= - 72 - = = Brown, D.K., & Moore, G. (2003). Rebuilding the Royal Navy, warship design since 1945. London: Chatham Publishing. NPS-AM-09-010 Davies, P.E., & Thornborough, A.M. (1996). The Harrier story. London: Arms & Armour Press. Denham, J.W., Krumenacker, J.L., D'Mello, G.W., & Lewis, M. (2002, January 23-25). Taking advanced STOVL flight control to sea: The VAAC follow-on research programme. Paper Presented at the American Helicopter Society Aerodynamics, Acoustics and Test and Evaluation Technical Specialists Meeting, San Francisco, CA. Fozard, J.W. (1978). The Jet V/STOL Harrier: An evolutionary revolution in tactical air power (AIAA Professional Study Series). Kingston Upon Thames, England: British Aerospace. Fry, A. (2008). CVF Ski-jump ramp profile optimisation for F-35B. In Proceedings of the International Powered Lift Conference, 22-24 July 2008. London: Royal Aeronautical Society. mêçÅÉÉÇáåÖë= Harrier.org.uk. (2009). Falklands War 25 years on—A nation remembers. Retrieved from www.harrier.org.uk çÑ=íÜÉ= Hodge, S.J., & Wilson, P.N. (2008). Operating JSF from CVF: The reality of simulation. In páñíÜ=^ååì~ä=^Åèìáëáíáçå= Proceedings of the International Powered Lift Conference, 22-24 July 2008. London: Royal Aeronautical Society. Ministry of Defence (MoD). (2009, April). Acquisition operating framework guide version 2.0.11. oÉëÉ~êÅÜ=póãéçëáìã= Retrieved April 6, 2009, from http://www.aof.mod.uk/aofcontent/operational/business/capabilitymanagement/capability management_whatis.htm Morrison, E.J., Docton, M.K.R., & Underhill, R.M. (2008). Improving carrier operation through the application of CFD to the CVF design process. In Proceedings of the International Powered Lift Conference, 22-24 July 2008. London: Royal Aeronautical Society. National Archive, File AVIA 6/25876—Assessment of Vectored Thrust aircraft to AST.403 in the Volume I: Maritime Role. Pryce, M.J. (2008). Descartes and Locke at the drawing board—Project design and ASTOVL Defense Acquisition in Transition aircraft procurement (D. Phil Thesis). Brighton, England: University of Sussex. Rolfe, R. (2008). Ski-jump launch performance studies in DSTL. In Proceedings of the May 13-14, 2009 International Powered Lift Conference, 22-24 July 2008. London: Royal Aeronautical Society.

Rosa, M.R. (2008). The status of the shipboard rolling vertical landing technique. In Proceedings of the International Powered Lift Conference, 22-24 July 2008. London: Royal Aeronautical Society. Published: 22 April 2009 Stanford, J. (2008, July 23). JCA–The UK carrier strike solution. Presentation at the International Powered Lift Conference, London.

Approved for public release; distribution is unlimited.

Prepared for: Naval Postgraduate School, Monterey, California 93943

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Additional Weapons additional missile during military amendment to the 2013 Defense operations. appropriation bill that would pre- Load Using Advanced According to Air Force special vent U.S. armed forces from pur- Fuels And Biofuels: advisor on energy and fuels, chasing high performance biofuels New Data Omar Mendoza, the Pentagon for military operations, unless Storm breaks out between U.S. has authorized additional testing they cost less than conventional military leaders and House with General Electric, Rolls-Royce, fossil fuels. Republicans. Can the U.S. afford and Pratt & Whitney to confirm Passage of the bill, which is to deploy fuels with advanced the findings from the Air Force now moving towards consider- war fighting capabilities? Research Laboratory, based ation by the full House, raises the Republicans say, for now, “no.” at Wright Patterson AFB, near possibility that U.S. military pilots (BIOFUELS DIGEST 21 MAY 12) Dayton, Ohio. could be forced, during periods of ... Jim Lane Mendoza added that, if the low prices for conventional fossil results seen at the extensive fuels, to carry one less missile, fly WASHINGTON, DC — New tests Wright-Patterson engine testing slower or be restricted in range, conducted at at Wright-Patterson labs are confirmed, outcomes during operational missions. Air Force Base have revealed could include consideration of that U.S. warplanes are capable Reduced Metal Fatigue next generation engines that can of flying faster and carry more take full operational advantage Mendoza offered the briefing payload on missions, when flying of the breakthrough in warplane at a roundtable meeting orga- with synthetic fuels, including performance. nized Friday in Washington by biofuels, compared to conven- the U.S. Navy, Department of tional military jet fuels made House Bill To Prevent Use Of Agriculture and Department of from petroleum. High Performance Fuels Energy, attended by high level The increased performance of The revelation of the test government officials, congres- biofuels could allow, for example, results comes less than one sional staff, and fuel industry a fully loaded F/A-18 SuperHornet week after the House Armed executives. Mendoza said that supersonic fighter to carry one Services Committee approved an the Wright-Patterson tests had shown that renewable fuels were about the test results but would fuels that I would be surprised lowering engine temperatures by need to undertake a highly if this data didn’t also apply to 135 degrees, owing to absence of detailed review in order to quan- those technologies, which also impurities found in conventional tify any operational or capital cost produce a synthetic fuel.” fossil fuels. savings that could be achieved by Other observers also took When those impurities changing the fuel mix. a cautionary approach to the burn, he explained, it causes He added that the tests reports, although they confirmed high temperatures to radiate showed that drop-in renewable that superior performance poten- throughout the engine, causing an fuels had, for the same volume, 7 tial was something that had been acceleration in metal fatigue. “At percent less mass, which lowered talked about for years in the mili- the temperatures that military jet the weight of the plane when fully tary and fuels communities, but engine perform at, an additional fueled, and made it possible for only testing facilities like the AFRL 25 degrees in temperature can the jets to fly faster, farther, or at Wright-Patterson had had the shorten the life of the engine by carry more payload. technical capability to measure half,” Mendoza said. He added that and quantify the gains. Industry Reaction the preliminary data showed that Although Senate energy staff- engine parts could last up to 10 Renewable fuels executives ers attended the briefing, no times longer, if the new high per- attending the roundtable were House staff were on hand, owing formance fuels were employed in pleased but cautious about the to the heavy calendar of activities place of conventional fossil fuels. new data. surrounding the imminent House Metal weakening from sus- “First of all,” explained vote on Defense appropriations tained high temperatures, as Imperium Renewables CEO John for 2013. most readers will recall, resulted Plaza, “it’s important news if it Activity On Capitol Hill in the collapse of three World gets confirmed, but we have to Trade Center buildings following wait for that confirmation. This Activity on Capitol Hill relating to the 9/11 terrorist attacks. has to be based on science. defense appropriations has inten- The Air Force’s chief engineers, Second, the Air Force is doing sified in recent weeks. In addition Mendoza said, had been briefed so much testing on coal to liquid to the proposed House ban on high performance fuels (unless guarantee sufficient demand for Pentagon, concurred in remarks they cost the same or less than the body armor so that it could made at Friday’s briefing, that the conventional fuels), Administration be produced commercially by situation with advanced biofuels officials have been lobbying defense suppliers, and supplied mirrors situations faced dozens strongly for permission to shift up quickly to U.S. troops serving in of times by the Pentagon for vital to $70 million in Navy appropria- the Middle East. materials. “We are not here to tions to support the commercial- Last year, Air Force Under- provide a subsidy. We are here to ization, at parity with the price secretary Erin Conaton under- ensure that commercial produc- of conventional fuels, of the high scored the chicken-and-egg prob- tion reaches levels where the performance renewables fuels. lem in comments to AFP. “The military can secure the supplies it big thing we’re trying to do is to needs at prices it can afford. We The Defense Production Act send a clear message to industry come in once, and we don’t come Last year, President Obama that the Air Force wants to be in back.” issued a finding that the fuels a position to purchase biofuels A battle has been brew- were vital to U.S. national secu- and to use that operationally ing between the House of rity, triggering Title III provisions for our fleet. But in order to do Representatives and the Pentagon in the Defense Production Act, that, we need industry to be able over funding of sufficient produc- which is used by the Pentagon to to produce in the quantities we tion to bring down the cost of the solve chicken-and-egg problems need at a cost-competitive price.” high-performance fuels to afford- in sourcing new technologies that Surveying the costs for fuels able levels, using the Defense are considered vital to U.S. war made in experimental quantities, Production Act. The House, citing fighting capabilities. Conaton added, “The biofuels cost concerns, has moved to For example, the Defense that are available now are just eliminate or block fuels funding Production Act was invoked sev- nowhere near the cost of what we for the Pentagon’s planned Green eral years ago when there was can buy JP-8 for.” Strike Force, which would deploy a public outcry over U.S. troops Matthew Seaford, Deputy the high performance fuels in a wearing insufficient body armor – Director for Defense Production carrier strike group commencing allowing the Pentagon to rapidly Act Title III activities at the in 2016. Chief Of Naval Operations the Navy Tom Hicks echoed Vice Adm. Philip Cullom Jonathan Greenert those remarks in a keynote Vice Adm. Philip Cullom, until this Meanwhile, Chief of Naval address at the Advanced Biofuels year serving as director, Chief Operations, Admiral Jonathan Leadership Conference, held last of Naval Operations Energy and Greenert, said that in his CNO month in Washington DC. “It Environmental Readiness Division, Sailing Directions that “our pri- would be helpful, in our view, if commented, “Our Navy is working mary mission is war fighting…the we were not buying fuel from to be resilient to any potential reach and effectiveness of ships people who do not like us,” he energy future. Pursuing sustain- and aircraft would be greatly said. able resources, such as alterna- expanded over the next 10 to 15 Us Navy Secretary Ray Mabus tive fuels that are drop-in replace- years, and added that the Navy ments, assures our performance U.S. Navy Secretary Ray Mabus would “use new technologies and and mobility while protecting us made a similar point in remarks operating concepts to sharper our from the volatility of the fossil made in a recent C-SPAN inter- war fighting advantage against fuel market.” view. “We’re moving away from evolving threats.” [fossil fuels] for one reason, that Speaking at the Naval Energy it makes us better war fight- Former Supreme Nato Forum last October, Admiral ers. We would never give these Commander Wesley K. Clark Greenert added “Energy trans- countries the opportunities to lates to warfighting now and it Former Supreme NATO build our ships, our aircraft, our translates in the future,” said Commander Wesley K. Clark, ground vehicles, but we give Greenert. We are making tan- addressing the Advanced Biofuels them a vote in whether those gible progress on the [energy] Leadership Conference, described ships sail and whether those air- challenge the Secretary has the the failure to develop alterna- craft fly or those ground vehicles given us.” tives to fossil fuels, because of operate when we allow them to early-stage price concerns, as Deputy Assistant Secretary Of set the price and the supply of “the single greatest U.S. policy The Navy Tom Hicks our energy and we’ve just got to failure of the past 40 years.” Deputy Assistant Secretary of move away from it.” Operation Free Group Of international price of oil. Secretary Mabus. “I love green Retired Generals And Admirals “The Navy is investing in energy. I’m not against it,” Forbes A group of retired generals advanced biofuels programs that said. “It’s a matter of priorities.” and admirals, members of the will enhance its power-projection House Republicans were Operation Free project at the capability. The Marines are opera- outraged last year when the Truman National Security Project, tionalizing common assets like U.S. Navy invested $12 million echoed the same ideas in a let- wind and solar power to decrease to purchase high performance ter to Senate Armed Services energy vulnerability. These fuels from companies such as chairman Carl Levin and ranking initiatives have been undertaken Solazyme and Dynamic Fuels (a minority member John McCain. in partnerships with American joint venture of Syntroleum and “We, the undersigned veterans firms and are creating jobs for Tyson Foods), to conduct certifica- of the United States military, join American workers. tion and safety tests across more security leaders of both parties than one dozen military aircraft, including a precision flying test by in recognizing that America’s reli- Reaction From Congress ance on oil is a serious threat to the Blue Angels. Republicans argued that the our national security. We call on Some Members of Congress, U.S. could not afford the Congress to support the military however, oppose these programs, defense investment, and Virginia as it leads the way in developing and in turn have faced wither- Republican congressman Randy the next generation of secure, ing criticism from the military Fowler lambasted Navy Secretary clean energy sources We cannot community. Ray Mabus, at a congressional drill our way out of the problem of “They choose to waste time hearing, for seeking $70 million energy security. Even if we flood by advocating policies that have to ensure sufficient production of the market with every drop of oil already proven to be failures and the fuels in order to meet military in both our proven and strategic attack the military for investing in demand. reserves, it will not be enough to prudent measures that will save “You’re not the secretary of the offset rising global demand. Gas lives,” said the group of military energy, you’re secretary of the prices would still remain high and leaders signing the Operation Navy,” the Virginia Republican told OPEC would continue to set the Free letter. Technical Fuel Performance Unlike cars and truck, aircraft that the radiative heat release “Synthetic Paraffinic Kerosene is a must lift the mass of fuel they from aromatics was higher subset of conventional jet fuel but carry and expend energy doing than from paraffins,” explained without the aromatics and most so. Thus the lighter SPK blended Dr. Freerks. “Omar Mendoza of the cycloparaffins,” explained fuels save some fuel consumption mentioned [in 2005-06] that the Robert Freerks of RLF Enterprises, simply because they are lighter. hot section of the engine is of the father of SPK fuels dating As probably 95% of all flights high concern for reliability and is back to 1999, when he worked for are not volume limited, this is an inspected for failure periodically. Syntroleum. instant fuel savings of roughly 2%. He indicated that a roughly 10C “There is nothing new in the “As for flight range, I noted drop in wall temperature results fuel, only the lack of some things that the lower density fuel should in doubling of the life of the hot that are found in conventional increase flight range for mass section. As there have been flight fuels. The major difference is the limited flight plans (say an F-18 accidents due to hot section fail- aromatics content, which impacts taking off from a carrier with ures, this is of interest. several performance attributes of full armament load and less “In the end, Omar is correct. the fuel including net heat con- fuel). Here the SPK blend weighs This analysis goes against older tent, temperature of combustion something like 1000 kg less thought, so it was resisted by (and radiant heat release), density, than the conventional fuel of the some, [who don’t] didn’t fully and conductivity. same volume. So, you could add understand the multiple issues “SPK have more hydrogen and another missile or the like for the going on here, the facts and data.” same volume of fuel. Plus the SPK have less energy per volume, but Price Performance the lighter SPK blend component blend will have more energy by The U.S. Navy is also concerned has more energy per mass. The about 4-5% than the conventional about the volatile price of con- difference is about 4%. Thus if a fuel, slightly increasing range.” ventional fossil fuels. Last year, plane is maxed out on cargo and The Technical Data On Heat the Navy was forced to slash limited in mass of fuel it can carry, “A paper by Linda Blevins of training and fleet operations in it will have more energy on board Sandia NL (2003) that indicated order to make up for $1 billion and can fly further on that fuel. in cost overruns, caused by the at least two aircraft carriers, after Then, the U.S. introduced the run-up in oil prices during 2011. acquiring its first carrier from 100-octane fuel, which allowed Every $1 increase in the cost of Ukraine last year. the Spitfire to fly faster and a barrel of oil results in a $31 As Edward Wong wrote in the higher, because of performance million increase in Navy fuel New York Times back in 2010, advantages in the fuel. expenditures. “The Chinese military is seek- Wikipedia adds: “With 100 ing to project naval power well octane fuel the supercharger of The Pacific Rim And Naval beyond the Chinese coast, from the Merlin III engine could be Power the oil ports of the Middle East to “boosted” [and] This increased House Republican leaders the shipping lanes of the Pacific, power substantially improved the accused the Navy and the Obama where the United States Navy rate of climb, especially at low to Administration of pursuing a has long reigned as the domi- medium altitudes, and increased green agenda, by employing the nant force, military officials and the top speed by 25-34 mph fuels, when conventional fuels analysts say…in March, Chinese up to 10,000 feet. During the were available at a lower cost. officials told senior American Battle of France and over Dunkirk They also criticized a demonstra- officials privately that China would RAF Hurricanes and Spitfires tion of the high performance fuels brook no foreign interference in were able to use the emergency by a carrier strike group, sched- its territorial issues in the South boost….The combination of CS uled for the Pacific Rim military China Sea.” propellers and 100 octane fuel exercises off Hawaii in late July. put the British fighters on par The Bottom Line Conversely, Chinese authori- with the Luftwaffe.” ties have sharply increased their “World War Two was a war all Mendoza puts it more simply, high performance and renewable about energy,” noted Omar and starkly. “Fuel can influence fuel production targets, at the Mendoza. “Take for example the the outcome.” same time as China is sharply European air theater. British air- http://www.hrana. increasing its naval forces, and craft were struggling to overcome org/news.asp# German fighters, because they was reported this past week to USWarplanes both ran on 87 octane jet fuel. have undertaken construction of CanFlyFaster

Sea-Based Aviation: these requirements in normal and has a longer stroke and higher load emergency situations. capacity. Both the US Marine Corps A National Naval and the US Navy variant have a 3.1 Joint Strike Fighter refueling probe on the right side Responsibility 09 May 2011 ...The F-35C is the Navy's first of the forward fuselage. Weapon 2.7 Flying Qualities & Performance stealth aircraft. US Navy carrier loads, cockpit layout, countermea- Shipboard operations introduce a operations account for most of the sures, radar, and other features are host of factors not present ashore. differences between the F-35C and common with the other variants. Many of these factors have a sig- the other JSF variants. The aircraft The F-35C's flight-test program nificant impact on the performance has larger wing and tail control sur- included a series of Field Carrier of the aircraft and associated flying faces to better manage low-speed Landing Practice tests to evaluate qualities. A safe shipboard landing carrier approaches. The extra wing the aircraft's handling qualities requires the aircraft to fly slow area is provided by larger leading- and performance during carrier enough to be recovered within the edge flaps and foldable wingtip approaches and landings at an capacities of the arresting gear sections. These components attach airfield, and also included up-and- while not imposing an unaccept- to the common-geometry wingbox away handling-quality tests and ably high requirement on the ship on the production line. A larger engine transients at varying speeds to generate wind-over-deck. Slow wing span provides increased range and altitudes. approach speeds cannot come at and payload capability for the Navy The JSF must be able to operate the expense of unsatisfactory flying variant. The aircraft, on internal from US and allied shore-based qualities; the aircraft must possess fuel alone, has almost twice the facilities. Considerations for basing robust waveoff and bolter capa- range of an F-18C. The design is suitability and shipboard compat- bilities (in multiple configurations), also optimized for survivability, a ibility in particular, include of a when an approach is waved-off key Navy requirement. wide range of complex integration (aborted) or when the arresting The F-35C has an increased issues such as: hook fails to engage the arresting capacity structure for absorbing • Approach flying qualities wire (bolter). This also implies that catapult launches and arrested • Catapult hookup propulsion systems must have landings. The aircraft has a carrier • Deck handling sufficient thrust response to meet suitable tailhook. Its landing gear • Deck spotting • Elevator compatibility the British Aerospace Hawk. Navy on the basis of a severe • Flight deck servicing Conversion of the Hawk aircraft to wing-drop behavior (aggravated by • Hangar deck maintenance a naval trainer with carrier capabili- the increased weight required to • Jet blast effects ties involved considerable Research strengthen the airframe for carrier • Landing systems and Development (R&D). In addi- operations). During the Navy's • Ship motion tion to the necessary strengthening flight evaluations, the wing drop • Shipboard environment of landing gear components and was so severe that uncommanded • Steam ingestion the inclusion of arresting gear, roll motions often exceeded 90 deg. For the Short Take-Off Vertical development work was required in The T-45 Program subsequently Landing (STOVL) variant, lift fans numerous areas that were critical adopted a wing redesign, which are an enabler of the naval avia- for carrier-based operations. Some incorporated wing leading-edge tion requiring solutions to many areas of concern included the slats. The slats virtually eliminated complex challenges crossing handling qualities, engine response the wing-drop tendency and low- multiple engineering disciplines. characteristics, and stall character- ered the carrier approach speed to For instance, ensuring efficient istics of the T-45. a more acceptable value. A more aerodynamic lift fan performance in Adapting the Hawk design to powerful and responsive engine, a high cross winds or robust designs the T-45 mission proved more modified rudder and other changes of lightweight clutch mechanism to technically challenging than had were also added to improve flight transfer shaft horsepower to the lift been estimated. In 1988, following characteristics during carrier fan without chatter or wear while extensive preliminary flight-test operations. ensuring high life...." evaluations, the Navy cited This program points to the com- several major deficiencies in the plex design modifications required 3.3 T-45C Development T-45. The engine lacked thrust and to adopt existing aircraft for carrier The T-45 aircraft is used for inter- responsiveness, and the aircraft operations and unanticipated S&T mediate and advanced Navy pilot lacked the lateral and longitudinal challenges that often emerge when training for jet carrier aviation and stability needed for carrier opera- assessing carrier suitability...." tactical strike missions. Its genesis tions. The stall characteristics of http://www.onr.navy.mil/en/Science- is found in the modification of an the initial T-45 configuration were Technology/Departments/~/media/ existing land based configuration, judged to be unacceptable by the Files/35/NNR-Sea-Based-Aviation.ashx