Future Trends in Short-Haul Air Transportation

1. Future Trends in Short-Haul Air Transportation Rajkumar S. Pant Aerospace Engineering Department Indian Institute of Technology - Bombay

2. Presentation Outline • Introduction • Civil V/STOL Market Needs • V/STOL Aircraft Concepts • V-22 Osprey Program • Technology Needs for Advanced Rotorcrafts • Infrastructure Needs • Vertiports

3. What is Short-Haul Air Transportation ? • Air travel over stage lengths   400 NM (644 Km) • Various modes • Trains, Automobiles, buses, ships, aircraft, rotorcraft • Major challenges • Increasing congestion of roads, airports and air corridors • Cost and environmental impediments in developing new airports • Inability of ground systems to adjust to changing demand patterns • Enormous capital cost for improving/extending ground systems • Possible solution • Air systems with Vertical / ShortTakeoff and Landing capability

4. 1958 US Army/Bell XV-3 Convertiplane US Army/NASA/Bell XV-15 Tiltrotor 1972 Pioneer VTOL Aircraft

5. Short-Haul Market Needs • Unacceptable delays • Infrastructure constraints • Shortage of slots at busy airports • Creation/Expansion of new airports not always possible • Prohibitive cost of land acquisition and development • New hub airport like DFW would require  18,000 acres of land • Cost around  $ 5 billion + terminal + handling + support costs • Tremendous public resistance • e.g. Narita in Tokyo, Gatwick in UK, Rewas-Mandhwa in Mumbai, …. • Large fraction of Short Haul traffic from hub airports • > 60% of all flights travel < 435 NM (805 Km) and last  1 hour • Time saving for business passengers • Requires reduction in total travel time • Reduced access time

6. Unacceptable Delays • Main reasons • Hub & Spoke route structure • Severe Congestion at major airports • No. of US airports with annual delay  20,000 hrs • 23 in 1991 (actual) costing $ 32 million • 32 in 2002 (projected) • Factors causing delay in US in 1993

7. Compound helicopter Thrust vectoring Tiltwing Tiltrotor V/STOL Aircraft Concepts

8. T I L T R OT OR S

9. Features of T iltrotors • Highest potential of capturing Short-haul VTOL transport • Major issues • Meeting attributes of commercial air market • VTOL • Reasonable speeds compared to current aircraft • Pressurization and passenger amenities • Acceptable safety levels • High reliability • Comparable Operating Costs • Possibility of production at reasonable cost • Replacement for commuter/corporate aircraft/helicopters • Acceptance by Aviation Industry • ATC Authorities, Airport Administrators and local community

10. V-22 Osprey Program

11. Transition from Helicopter to Aircraft

12. Aircraft Mode Rotorcraft Mode Tiltrotor Control Mechanism

13. Flight Envelope Range-payload Capability V-22 versus Helicopters

14. European Tiltrotor studies EUROFAR Civil Tiltrotor • Participating countries • France (Aerospatiale) • Germany (MBB) • U. K. (Westland) • Italy (Agusta & Aeritalia) • Spain (CASA) • Studies related to • Technology Selection & Evaluation • Preliminary Design • Experimental activities on critical components & systems • Certification and Airworthiness • Market research & Economic evaluation

15. Boeing/NASA/FAA/USDoD study • Conclusions of the study (1986 - 1991) • CTR has large market potential in high density market • CTR is superior to multi engine helicopters due to • Higher speed and range • Lower operating costs • Better community and passenger acceptance • CTR is competitive with fixed wing airplanes due to • Time saving and greater convenience • Recommendations • Establish commercial Tiltrotor transportation network • Extend Tiltrotor technology to meet Civil needs • Develop operational standards and Vertiport Terminal Instrument Procedures • Modify ATS to exploit unique capabilities of Tiltrotor

16. Challenges for Advanced Rotorcraft USER COMMUNITY Environmental Considerations Noise Comfort Safety Economic Considerations Affordability TECHNOLOGICAL READINESS Dispatch Reliability OPERATOR

17. Safety and Passenger Acceptance • Safety • Meeting minimum standards not sufficient for a new system • High cost of insurance • Able to fly away or safely land in case of engine failure • Passenger acceptance • Convenient schedules, which are met with minimum delays • Higher mechanical reliability & lower unscheduled maintenance • All Weather operation capability • Advanced Vehicle and Air Traffic Control systems • Comfort • Lower vibration and cabin noise levels

18. Typical aircraft vibration levels

19. Environmental factors and Cost • Environmental factors • Noise, Emissions, Ground Transportation, Parking & land use • Community acceptance not ensured by meeting FAA/ICAO standards • Initial and Operational Cost • Comparable to conventional aircraft • Lower development and manufacturing cycle times • Empty weight reduction • Higher speeds for reducing block times • Lower Production and Maintenance cost

20. Operating costs of Tiltrotors

21. All weather operation • Proper design of man-machine interface • Reducing pilot workload by appropriate control laws & displays • Enhanced navigation and guidance information • Automation of many control functions • GPS & DGPS for accurate and reliable navigation in bad weather • Low power De-Icing

22. Specific Markets Served by Tiltrotors • Corporate/Executive • Public Service • Police, medical, border patrol, drug enforcement, SAR, Fire-fighting • All weather capability and IFR operations • Resource Development • Transport of crew to offshore oil rigs • MTOW  40000 lbs.. • Cargo/Express Package • Courier and Freight services • Inter-metropolitan routes, low ground time, late package pickup time • Low Density Transport • High Density Transport

23. CUMULATIVE REQUIREMENT Ref.: Clay et al. Civil Tiltrotor Missions and Applications; Summary Final Report, Boeing Commercial Airplane Company, NASA CR 177452, 1987 Market Forecast for Tiltrotors

24. Vertiports • Current infrastructure centered on fixed-wing aircraft • Advisory circular for Vertiport design • Setting up cost $ 5 million - $ 40 million (one tenth of airport) • Max. access time 30 minutes by road during peak hours • Located near the center of density of travelling public • Three types of Vertiports • Urban •  5 acres of land required • approach and departure paths over water • Edge-of-city •  20 acres of land required • located above a highway, highway interchange or hub airports • Full-service remote • facilities for fuelling and light maintenance • mass transit /freeway access to high-density populated areas

25. Atop a Building On the Sea Front Urban Vertiports

26. Edge of City Vertiport

27. Air Traffic Management of Tiltrotors • General Issues • Enroute ATM requirements comparable to advanced turboprops • Steeper approaches for noise abatement • Horizontal attitude maintained during approach • Increased passenger comfort and pilot visibility • FAA efforts in ATM of CTR • General Aviation Vertical Flight Program Office set up • Study of CTR operation between New York & Boston • CTR service will not interfere with conventional aircraft • Study the impact of CTR introduction in the Northwest corridor • CTR service will increase flexibility of air service without congestion • Terminal Instrument Approach Procedures being developed • IMC operations of rotary wing aircraft, using DGPS

28. PRIORITY (%) Ref.: Schleicher & Alexander, Technology Development for Advanced Tiltrotor Transports Proceedings of AIAA Intl. Powered Lift conference, Santa Clara, CA, USA, Dec. 1993 Inhibitors to Civil Tiltrotor Service

29. Bell-Agusta BA609 Civil Tiltrotor

30. Thanks for your attention !Any Questions ??