Modern Airships The Big “Green” Thing in the Sky Ron Hochstetler Aviation Sector Manager [email protected] 1 Ron Hochstetler Lighter-Than-Air Expertise • Director, SAIC LTA Programs • Deputy Program Manager for SAIC SKYBUS 80K UAS airship • Project Manager US Army “Transport Airship” Study • Technical support to Phase I DARPA ”ISIS” stratospheric airship program • Senior Project Analyst for CargoLifter GmbH, Germany • Program Manager supporting US Navy Airship Program Office • Tour Manager for Airship Industries commercial airship • Assistant to Program Manager for Airship Industries YEZ-2A Navy airship • Mechanic/Assembler on Helistat heavy lift hybrid airship US Navy YEZ-2A Airship Mockup CargoLifter Heavy Lift Airship Concept DARPA ISIS Stratospheric Concept Piasecki Helistat Hybrid Airship 1988 Pepsi Airship Tour SAIC SKYBUS 80K 2 Airship Types Three general types 3 Airship Design Basics . Lighter-than-air gas (helium) provides airships with continuous “static” lift . One cu. Meter of Helium Lifts One Kilo! • High payload volume • High payload lift – Hindenburg had 100 ton payload • High in-flight stability • Speed range - 0 to 90 mph – High aerodynamic drag on hull – Low aerodynamic constraints on cargo • Energy needed to propel and lift the airship and payload is very low • High fuel efficiency (an order of Hindenburg Exiting its Hangar magnitude better than jet of equal payload) • Lower fuel consumption yields – Low carbon emissions – Very long flight endurance – Very long unrefueled ranges – Low vibration – Low noise signature Total Engine Power of Hindenburg (100 ton payload) Equal to One Engine on C-130 (20 US Navy Patrol Airship Ton Payload) 4 Airship Design Basics (cont.) • Require little ground infrastructure and can operate in austere locations • Investment is in the airship not in the ground infrastructures • Can accommodate crews onboard for several days • Refueling, re-crewing, re-supply, and basic maintenance can be done while in flight In-flight maintenance on Zeppelin N 07 Operations in Winter Graf Zeppelin Mock Up of Hindenburg Layout for Two-person Cabin on 1987 Passenger Area US Navy Patrol Airship Concept 5 Design Configurations Fully buoyant Semi-buoyant • Conventional ellipsoid • Hybrid-rotary • Lenticular • Hybrid-lifting body • Other shapes • Hybrid-winged Conventional Ellipsoidal Airship Lenticular Semi-Rigid Airship Hybrid-Winged Hybrid-Lifting body Hybrid-Rotary 6 Mission Optimizations Two main applications for airships 1. Persistent presence, optimized for long endurance from sea level to medium altitudes in areas to be supported. Missions include intelligence, surveillance, and reconnaissance (ISR), communication links, maritime patrol, civil police patrol. Manned or unmanned. 2. Transport, optimized for loading, transport, and unloading of freight (or passengers). Cargo can be bulk, liquids, pallets, containers, vehicles, or project equipment. Manned operations. Two categories of transport airships 1. Long distance carrier, optimized for speed and low drag for transport over long distances. Some designs land vertically while others require landing fields. 2. Short distance flying crane, optimized for precision lift and payload placement. Typically has higher drag and lower speed, but has active controls to enable precision hovering payload operations. 7 Airship Mooring Systems Airship operations can be supported from fixed or mobile mooring masts Basic Expeditionary Mast Mobile Mooring Mast Vehicle Zeppelin Semi-Automated Mobile Mooring Mast Road Transportable Mobile Mast Trailer 8 Airship Hangars • Large airships need large hangars for construction and annual maintenance • All other operations can be supported from fixed or mobile mooring mast systems Three airships in TCOM aerostat hangar in Elizabeth City, NC Zeppelin N 07 airship under construction in CargoLifter hangar in Germany German airship hangar 9 Airships Today Airships represent the “unexploited” aviation technology Modern Airship Designs • High strength-to-weight fabrics • Composite material construction Skyship 600 Gondola Zeppelin N 07 Cockpit • Computerized flight controls • Semi-automated ground handling • Vectoring propellers Airship Operations Vectoring Propellers • Fully mobile and can operate out of small airports or open areas • Ground crew, can be as few as one person • Weather limits, similar to helicopters – Winds of 35 mph or less are preferred Zeppelin N 07 Airship Moored to Semi- – Max wind tolerance when moored is 90 mph automated Mast 10 Current Airship Manufacturers/Operators Only a handful of airship manufacturers and operators • About a dozen airships currently operating in the world • Small companies with limited resources • Most airship operations are owned by the airship manufacturer • Very small number of experienced operations personnel – There are more astronauts than airship pilots! Goodyear GZ-20 Airship Services Skyship 600 B American Blimp Corp Lightship A-150 Zeppelin N 07 Aeros Corp 40-D RosAeroSystems Au-30 11 High Altitude Unmanned Applications • Strong interest for unmanned airships operating in the stratosphere – Supports telecomm services and intelligence, surveillance, and reconnaissance (ISR) missions • Average wind speed drops down significantly around 72,000 ft. – Just two significant high wind events at these altitudes annually • Airships can serve as “low altitude” satellites operating up to a year above a geographic point 12 Cargo Applications General airship cargo applications • Between multi-modal shipping centers (trucking terminals, etc.) • Within remote or otherwise inaccessible regions Primary freight transport missions • Shipping perishable food, fuel, equipment, and supplies • Delivery of materials, equipment, prefab structures, etc…for mining or construction projects (replace ice roads in Canada, Alaska, and Siberia) – Permits “just-in-time” movement of materials and supplies; reduces on-site storage, shortens project schedules, and reduces project costs • Moving outsized or heavy “project freight” • University of Manitoba forecast Canada could use between 185 and 635 airships, of 50 metric tons lift Ice Road Truck Arctic Inuit Village Equipment Transport Canadian Diamond Mine 13 Vertical Lift for Precision Positioning Transport equipment difficult to move by conventional means • Install pre-fab windmills and hydro generation equipment in optimized locations • Electrical grid installations – Towers, transmission lines, switches, transformers, etc. • Move oil and gas drilling systems and pipeline equipment around environmentally sensitive areas Deliver equipment to meet short-term production needs • Airship transport reduces handling steps, point-to-point distances, overall transport time, and overall expense • Production equipment and facilities can be leased on as needed basis Hoisting Propellers Generator Moving Through a Village Positioning Bridge and Rail Segments onto Windmills 14 CargoLifter CL-160 Development Designed to transport 160 metric tons! • Fly-by-wire flight control system • Computer controlled propulsion and positioning systems • Vertical thrusters provide 40 tons of lift. Bow/stern thrusters provide positioning stability during load exchanges and mooring • Semi-rigid graphite composite tubular keel • Envelope of multiple layers of Vectran Coated w/ Tedlar • 16 GE turbo shaft engines for primary propulsion, station keeping, and ship’s power CargoLifter CL-160 Aerial Crane Airship Concept 15 CL-75 Cargo Balloon Largest recent LTA vehicle built • CL-75 constructed by CargoLifter in 2000 • Cargo container tethered below the balloon • Designed to be towed by large helicopter, surface ship, or ground vehicle 55 ton German Mine Area Tank Inside CL-75 Load Frame CL-75 Cargo Balloon Lifting Tank • Diameter: 61 meters (200 ft.) • Volume: 110,000 cu. Meters helium – More than half the gas volume of the Hindenburg! • Gross lift: 100 metric tons • Useful lift: 75 metric tons • Altitude: 2,500 ft above sea level • Towing speed: up to 70 km/hr. • Range: 250 km CL-75 Cargo Balloon Being Towed from its Hangar • Cost to build: $10 million (approx.) 16 “Rise of the Hybrids ” 1960’s Goodyear Hybrid Concept 1960’s Goodyear Rotary Hybrid Concept HAV Long Endurance Lockheed Martin P-791 Lifting Body Hybrid Aeros Pelican Lifting Body Hybrid Multi-Int Vehicle (LEMV) Aerovehicles Aerocat Dynalifter Winged Hybrid Skyhook Rotary Hybrid Concept 17 What Does the Future Hold???? 18 SAIC Optimized Airship Routing (SOAR) System SAIC has a tool that provides optimal route planning for airships operating in inclement weather • Routes are broken into multiple short flight segments • Each segment is tested against the performance metric • Only the best segment is retained in each step – Uses recursive definition of routes – Branching is constrained by factors such as nearness to destination and current direction of travel Destination Start • 1 million routes are sampled per run ‒ Routes restricted to circular region with GCR as its diameter ‒ Routes constrained within pre-determined angular sector The dots represent way-points ‒ New routes weighted by the previous heading generated for each route ‒ New routes are also weighted by the heading towards the final destination 19 Green Airship Propulsion Employ engines that burn heavy fuel or bio-diesel – Airships promote safer in-flight development of high power-to-weight engines – Engines can run on a variety of “heavy” fuels – Can also be configured to run on hydrogen fuel – Need power to weight ratio equal to turboprop engines