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QinetiQ MK 10A Ejection Seat Modifications (2197 & 2198) for Tornado GR4/4A and F3 Aircraft Phase Two QINETIQ/AT&E/CR00782/1 Cover + x + 70 pages December 2002 41.1111110k This document is subject to the release conditions printed on the reverse of this page This document is issued for the information of such persons only as need to know its contents in the course of their official duties. Any person finding this document should hand it to a British Forces unit or to a police station for safe return to the Chief Security Officer, QINETIQ Ltd, Cody Technology Park, Farnborough, Hampshire GU14 OLX, with particulars of how and where found. THE UNAUTHORISED RETENTION OR DESTRUCTION OF THE DOCUMENT IS AN OFFENCE UNDER THE OFFICIAL SECRETS ACT OF 1911 - 1989. (When released to persons outside Government service, this document is issued on a personal basis and the recipient to whom it is entrusted in confidence within the provisions of the Official Secrets Acts 1911 - 1989, is personally responsible for its safe custody and for seeing that its contents are disclosed only to authorised persons.) Customer Information Customer Reference Number TOR3/09/97BD Task Title MAR Recom. for Ejection Seat Upgrade Customer Contact Name Tor9c,1111111111111 Staff Requirement/Target Project Number C8FFT/014 Milestone Number Date Due (dd/mm/yyyy) 26/11/1999 This document contains commercially valuable information controlled by QinetiQ. Intellectual Property Department must by consulted before it is released outside QinetiQ. © Copyright of QinetiQ ltd 2002 This document is intended for internal use only ii QINETIQ/AT&E/CR00782/1 Authorisation Prepared by 111111111111110°—' Title Trials Officer Signature Date Location BCE Authorised by 411.11111111.11 Title Technical Manager Air Launched Munitions Signature Date Principal authors Name 111111111111111111111 Appointment Tornado Project Manager Location BCE QINETIQ/AT&E/CR00782/1 iii RESTRICTE11' Record of changes Issue Date Detail of Changes 1 December 02 Initial Issue 111011*A• iv QINETIQ/AT&E/CR00782/1 RESTRICTED Executive summary Phase Two modifications to the Mk10A ejection seat fitted to the Tornado GR4/4A and F3 aircraft were incorporated to address the extended aircrew mass range that was apparent in the RAF. The original specification range for nude mass of aircrew in 1975 was 56.56kg to 97.34kg. The new specification for nude mass is 50.98kg (female aircrew) to 107.86kg. This equates to boarding masses of 67.5kg to 135kg wearing full AEA. The weight of Aircrew Equipment Assemblies (AEA) and the mass of the seat itself have all increased since the introduction of the Tornado aircraft and Mk10A ejection seat. Modification 02198 involved the replacement of the GQ1000 Mk2 parachute assembly (incorporated during the Phase One modifications) with the GQ5000 parachute and it's associated deployment system. The GQ5000 properties include a drive capability and a reduced rate of descent, as well as a reduced lines taught snatch load. It also incorporates a selectable steering capability, which offers the aircrew improved manoeuvrability and a reduced forward speed on landing if utilised correctly. Modification 02197 involved the replacement of the original primary and secondary ejection gun cartridges with revised cartridges offering a reduced Dynamic Response Index (DRI) value (resulting in a reduced risk of injury, especially to the minimum weight ejectee), whilst maintaining an acceptable velocity (of the seat) on separation from the ejection gun (especially for the maximum weight ejectee). The revised cartridges offer a reduced DRI on the primary cartridge phase of operation, but increase the force during the secondary phase of operation to ensure sufficient velocity on seat/ejection gun separation. The assessment of the GQ5000 and its deployment system (Mod 02198) concluded that it was acceptable with regard to zero/zero ejection situations (in conjunction with the revised ejection gun cartridges) with the revised heavy weight seat occupant. It also performed satisfactorily (in conjunction with the revised ejection seat gun cartridges) in the high-speed sled test (initiation at 608kts). The system successfully passed all environmental trials, but had to have the low temperature specification altered, with the system being cleared for -50°C rather than the original -60°C. This occurred due to the two ply butyl rubber of the deployment inflation bladder failing after a soak at -60°C. The new higher temperature of -50°C was considered acceptable (system tested satisfactorily at -54°C). Resurgence of the packed parachute was found after further environmental trials and amounted to 4mm. This amount of resurgence was considered acceptable. The clearance between the upper surface of the headbox and the lower surface of the aircraft canopy, specifically the Linear Cutting Cord (LCC) was found to be acceptable. Modifications to the top flap of the headbox, which consisted of the introduction of a kevlar insert, and cross-stitching, ensured that little or no damage would occur to the fabric top flap should the LCC detonate within either a very close proximity, or in physical contact. Reconfiguration of the Drogue Withdrawal Line (DWL), with regard to reduction in the armoured sleeve and alterations to the stitching pattern resulted in a significant reduction in packed headbox height. The assessment of the revised primary and secondary ejection gun cartridges (Mod 02197) concluded that the performance of the system was much improved over that achieved in the original Mk10A ejection seat qualification programme in regards to the DRI. The worst case scenario for the value of the DRI (high temperature (+70°C) cartridges, minimum weight seat occupant) produced a value of 20.44 (17% chance of injury), which compares favourably with the maximum allowable DRI in this situation of 22.2 (40% chance of injury). The worst case scenario for velocity at seat/ejection gun separation (-40°C cartridges, maximum weight seat occupant) was marginally reduced, but was still considered acceptable. However, the values for the maximum QINETIQ/AT&E/CR00782/1 speed at which a heavy weight seat occupant can eject from the rear seat position and avoid a `hard' contact with the Tornado tail fin have been reduced (from the original specification of 625 Knots Calibrated Air Speed (KCAS)). The values now stand at 617 KCAS or below for the Interdictor Strike (IDS) aircraft and 622 KCAS or below for the Air Defence Variant (ADV) aircraft. The lower of the maximum airspeeds (617 KCAS) should be used for both aircraft types resulting in a single ejection envelope graph being produced for all Tornado documentation. The revised simplified combined harness (introduced during Phase One modifications) was shown to be able to withstand the dynamic parachute inflation forces produced by a maximum weight ejectee and also the Tornado specification 40g impact forces produced by a maximum weight seat occupant in the event of an aircraft crash. However, the ejection seat mounting points which attach the seat/occupant to the structure of the aircraft were not able to withstand the increased forces generated by a maximum weight seat occupant in a 40g crash scenario (original Tornado specification). The mounting points and the aircraft bulkhead were theoretically calculated to be able to withstand an impact force of 34g with a maximum weight seat occupant. Due to this, the specification for impact survivability has been reduced to a value of 34g. Assessment of the GQ5000 parachute steering facility in a suspension trial highlighted difficulties in use due to the location of the steering handles on the parachute risers and the size of the handles themselves. This was compounded by the fact that location of the handles could only be achieved via feeling up the parachute risers. Bulky AEA (especially with an inflated life preserver) and an ejectee with a short functional reach added to the difficulties. However, the system was able to be used and was considered to improve the chances of survival of an ejectee by allowing a steering facility for avoidance of hazards when landing. Many other minor alterations were necessary due to the embodiment of the Phase Two modifications, such as the replacement of the drogue release 'scissors' shackle with a Gas Shackle (GS), replacement of the Barostatic Time Release Unit/Manual Override (BTRU/MOR) cartridges with improved items and replacement of the Breech Type Time Delay Firing Unit (BTTDFU) with the Gas Fired Time Delay Unit (GFTDU). QinetiQ is able to support the implementation of the Phase Two modifications 02197 and 02198 with regard to the Mk10A ejection seats fitted to the Tornado GR4/4A and F3 aircraft. However, some limitations exist with regard to the maximum ejection speed, the revised -50°C low temperature limit and 34g-impact value. Consideration should also be given to the training of aircrew on the use of the GQ5000 parachute. The escape system envelope for the fully modified Mk10A ejection seat fitted to the Tornado ADV and IDS type aircraft would be 0-617kts, 0-50,000ft for all aircrew. vi QINETIQ/AT&E/CR00782/1 List of contents Authorisation iii Record of changes iv Executive summary List of contents vii List of Figures ix 1 Introduction. 1 1.1 Task Number. 1 1.2 Originator. 1 1.3 Background. 1 1.4 Phased Introduction of Modifications. 2 1.5 Assessment Philosophy. 2 2 Description of Equipment. 4 2.1 GQ 5000 Parachute Assembly (Mod 02198). 4 2.2 Simplified Combined Harness Assembly. 5 2.3 BTRU/MOR Cartridges. 5 2.4 Primary and Secondary Gun Cartridges (Mod 02197). 6 2.5 Aircraft Canopy and Associated Jettison System. 6 3 Assessment of Evidence. 8 3.1 GQ 5000 Parachute and Bladder Inflation System Zero/Zero. 8 3.2 GQ 5000 Parachute and Bladder Inflation System 625Kts. 9 3.3 GQ 5000 Parachute and Bladder Inflation System Environmental Qualification.

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