The power plant and drive systems in a conventional helicopter cause high development and operating costs, compromise safety, and introduce performance limitations. Even though much effort is devoted to mechanical transmission systems, the use of electric components promises a higher reliability. Magnetic gearboxes address many of the problems in mechanical transmissions, but proved to be too heavy at this time. However, since this technology has not achieved its full potential, improvements are imminent and could allow its implementation in the near future. Several combinations with energy sources, amongst which liquid hydrogen (LH2), showed a turboshaft with kerosene to offer the lightest configuration. For the lower required power range, Avgas piston engines should at least be replaced with more efficient diesel engines. The possibility of using electric motors, such as the switched reluctance motor, to drive the tail rotor is possible at the expense of weight. The use of LH2, which has a threefold higher energy density than kerosene, in a helicopter seems feasible; though heavier due to an increased helicopter volume and tank weight, it offers a free cold source for high-performing high-temperature superconductive devices.
Million, D. J. Research requirements to reduce maintenance cost of civil helicopters, NASA CR, 145288, 1978.
3.
BuysschaertFHendrickPNewmanSConventional helicopters and their adaptiveness for more electric and alternative transmission technologiesIn 36th European Rotorcraft Forum, Paris, France, 7–9 September 2010, pp. 1–16.
4.
BennettJ WJackA GFault-tolerant control architecture for an electrical actuatorIn 35th Annual IEEE Power Electronics Specialists Conference, Aachen, Germany, 20–25 June 2004, pp. 4371–4377.
BurnsJ WAircraft cost estimation methodology and value of a pound derivation for preliminary design development applicationsIn 53th Annual Conference of Society of Allied Weight Engineers, Inc., Long Beach, California, USA, 23–25 March 1994, no. 2228, pp. 1–44.
7.
Beltramo, M. N. Parametric study of helicopter aircraft systems, costs and weights. NASA CR-152315, 1980.
8.
SostilioNWeight control overview S-92 medium lift helicopter program, Society of Allied Weight Engineers, Inc, 1997, pp. 1–31 (Bellevue, Washington).
9.
Alvarez, M. C. Economics of air transport. NASA TT F-15249, 1974.
10.
Liebeck, R. H., Andrastek, D. A., Chau, J., Girvin, R., Lyon, R., Rawdon, B. K., Scott, P. W., and Wright, R. A. Advanced subsonic airplane design and economic studies. NASA CR-195443, 1995.
11.
CaleD BContributions of the engine R&D community to reduce cost of ownership of army helicopters15th AIAA/SAE/ASME Joint Propulsion ConferenceLas Vegas, Nevada, 18–20 June 1979, no. AIAA 79-1360, pp. 1–7.
12.
CraigGMD500 main rotor drive system, high power high reliability low cost low weight, ed. AHS 51st Annual Forum, May1995, 9–11 (Fort Worth, Texas).
13.
National Transportation Safety Board. US Air Carrier Operations, calendar year 2005, annual review of aircraft accident data, 2009 (National Transportation Safety Board, Washington).
Krantz, T. L. NASA/Army rotorcraft transmission re- search, A review of recent significant accomplishments. NASA TM-106508, 1994.
21.
Krantz, T. L. and Handschuh, R. F. Efficiency study comparing two helicopter planetary reduction stages. NASA TM-103106, 1990.
22.
Folenta, D. and Lebo, W. Design, manufacture, and spin test of high contact ratio helicopter transmission utilizing self-aligning bearingless planetary (SABP). NASA CR 4155, 1988.
23.
Folenta, D. J. Design study of self-aligning bearingless planetary gear (SABP). NASA Contract NAS3- 21604, 1983.
24.
Henry, Z. S. Bell helicopter advanced rotorcraft transmission (ART) program. NASA CR 195479, 1995.
25.
Rashidi, M. and Krantz, T. L. Dynamics of a split torque helicopter transmission. NASA TM-105681, 1992.
26.
White, G. 3600 HP split torque helicopter transmission. NASA CR 174932, 1985.
27.
Chaiko, L. Assessment of worm gearing for helicopter transmissions. NASA Technical Memorandum 102441, 1990.
28.
RekikMBesbesMMarchandCMultonBLoudotSLhotellierDHigh-speed-range enhancement of switched reluctance motor with continuous mode for automotive applications. Eur. Trans. Electr. Power, 2008, 18, 674–693.
29.
AtallahKDesign, analysis and realisation of a high-performance magnetic gear. IEEE Proc. Electr. Power Appl., 2004, 151(2), 135–143.
30.
NagrialM HRizkJHellanyADesign and development of magnetic torque couplers and magnetic gearsIn IEEE’07, Lahore, 11–12 April 2007.
31.
HuangC CTsaiM CDorrellD GLinB JDevelopment of a magnetic planetary gearbox. IEEE Trans. Magn., 2008, 44(3), 403–412.
32.
TsurumotoKBasic analysis on transmitted force of magnetic gear using permanent magnet. IEEE Transl. J. Magn. Jpn, 1992, 7(6), 447– 452.
33.
YaoY DHuangD RHsiehC CChiangD YWangS JYingT FThe radial magnetic coupling studies of perpendicular magnetic gears. IEEE Trans. Magn., 1996, 32(5), 5061–5063.
34.
JianL NChauK TZhangDJiangJ ZWangZA magnetic-geared outer-rotor permanent magnet brushless machine for wind power generationIndustry Applications ConferenceNew Orleans, Los Angeles, 23–27 September, IEEE 0197-2618/07.
35.
RasmussenP OAndersenT OJørgensenF TNielsenODevelopment of a high-performance magnetic gear. IEEE Trans. Ind. Appl., 2005, 41(3), 764–770.
36.
MMPA. Standard specifications for permanent magnet materials. MMPA Standard No. 0100-00, Magnetic Materials Producers Association, Chicago, Illinois, USA, 2009.
37.
JørgensenF TAndersenT ORasmussenP OThe cycloid permanent magnet gear. In Industrial Applications Conference. IEEE, Tampa, Florida, 2006, 8–12, October 2006, 1-4244-0365-0/06.
38.
Rens, J., Atallah, K., Calverley, S. D., and Howe, D. A novel magnetic harmonic gear. In Electric Machines and Drives Conference, IEEE, Antalya, 3–5 May 2007, 1-4244-0743-5/07.
AIRB PHandbook of products, 2000 (AIR BP, Hertfordshire, UK).
41.
KnotheG‘Designer Biodiesel’: optimizing fatty ester composition to improve fuel properties. Energy Fuels, 2008, 22, 1358–1364.
42.
AkridgeJ RMikhaylikYLithium-sulfur secondary battery: chemistry and practical system performanceIn International Conference on Polymer Batteries and Fuel Cells, Las Vegas, Nevada, USA, 12–17 June 2005.
KrishnanRBlandingDBhanotAStaleyA MLoboN SHigh reliability SRM drive system for aerospace applications29th Annual Conference of the IEEERoanoke, Virginia, 2–6 November 2003, 0-7803-7906-3/03 IEEE.
48.
JackA GMecrowB CHaylockJ AA comparative study of permanent magnet and switched reluctance motors for high performance fault tolerant applications. IEEE Trans. Ind. Appl., 1996, 32(4), 889–895.
49.
UematsuTWallaceR SDesign of a 100 kW switched reluctance motor for electric vehicle propulsion. In APEC’95 conference proceedings, Dallas, Texas, 5–9 March 1995, vol. 1, pp. 411–415.
50.
KachapornkulSJitkreeyarnPSomsiriPTungpimolrutKA design of 15 kW switched reluctance motor for electric vehicle applicationsIn Proceedings of International Conference on Electrical Machines and Systems, Seoul, Korea, 8–11 October 2007, pp. 1690–1693.
51.
ChanC CChauK TAn advanced permanent magnet motor drive system for battery-powered electric vehicles. IEEE Trans. Veh. Technol., 1996, 45(1), 180–188.
52.
MassonP JLuongoC AHTS machines for applications in all-electric aircraftIn Power Engineering Society General Meeting, Tampa, Florida, 24–28 June 2007, IEEE 1-4244-1298-6/07.
53.
KwonY KBaikS KLeeE YLeeJ DKimY CMoonT SParkH JKwonW SLeeS HHongJ PJoY SRyuK SStatus of HTS motor development in KoreaIn Power Engineering Society General Meeting, Tampa, Florida, 24–28 June 2007, IEEE 1-4244-1298-6/07.
54.
Berton, J. J., Freeh, J. E., and Wickenheiser, T. J. An analytical performance assessment of a fuel cell-powered small electric plane. NASA/TM-2003-212393, 2003.
55.
Serenus. Serenus fuel cell evaluation kit, 2009 (High temperature PEM fuel cell system brochure).
56.
BosselUInvited Paper. On the way to a sustainable energy future, ed. September2005, 18–22 (Intelec ’05, Berlin).
57.
Brewer, G. D., Morris, R. E., Davis, G. W., Versaw, E. F., Cunningston, G. R., Riple, J. C., and Baerst, C. F. Study of fuel systems for LH2-fueled subsonic transport aircraft. NASA CR-145369, 1978.
58.
Verstraete, D. The potential of liquid hydrogen for long-range aircraft propulsion. PhD Dissertation, Cranfield University, Cranfield, UK, 2009.
59.
BastienJHandlerCHydrogen production from renewable energy sourcesIn EIC Climate Change Technology, Ottawa, Ontario, 10–12 May 2006, IEEE 1-4244-0218-2/06.
60.
BosselUDoes a hydrogen economy make sense?. Proc. IEEE, 2006, 94, 1826–1837.
61.
VerstraeteDHendrickPParametric sizing of more-electric regional jet aircraft with hydrogen fuel, 2008 (Sizing of the fuel tank, Deliverable D2/6 Add.A, Addendum A).
62.
VerstraeteDHendrickPPilidisPRamsdenKHydrogen fuel tanks for subsonic transport aircraft. Int. J. Hydrogen Energy, 2010, 35(20), 11085–11098.
63.
BarronR F. In: ScurlockR G (ed.) Cryogenic systems, edition 2, 1985 (Oxford University Press, Inc, New York).
64.
MecrowB BAtkinsonD JJackA GGreenSHaylockJ AThe need for fault tolerance in an aeroengine electric fuel control system, ed. November1999, Vol. 9 (In IEE Colloquium, London).
65.
Choi, B. B. and Siebert, M. A bearingless switched-reluctance motor for high specific power applications. NASA/TM-2006-214486, 2006.
66.
KlungR DGriggsMReliability and availability of megawatt drive conceptsIn 2004 International Conference on Power System Technology – POWERCON 2004, Singapore, 21–24 November 2004.
67.
SheahenT PMcConnellB WMulhollandJ WMethod for estimating future markets for high-temperature superconducting power devices. IEEE Trans. Appl. Supercond., 2002, 12(2), 1784–1789.
68.
LewisCMüllerJA direct drive wind turbine HTS generatorIn Power Engineering Society General Meeting, Tampa, Florida, 24–28 June 2007, IEEE 1-4244-1298-6/07.
69.
NerowskiGFrauenhoferJRiesGNickWNeumüllerH WAdvances and prospects of HTS rotating machine development at SiemensPower Engineering Society General MeetingDenver, Colorado, 10 June 2004, vol. 2, pp. 2052–2055.
70.
SivasubramaniamKZhangTLokhandwallaMLaskarisE TBrayJ WGerstlerBShahM RAlexanderJ PDevelopment of a high speed HTS generator for airborne applications. IEEE Trans. Appl. Supercond., 2009, 19(3), 1656–1661.
71.
WoodruffSBoenigHBogdanFFikseTPetersenLSloderbeckMSnitchlerGSteurerMTesting a 5 MW high-temperature superconducting propulsion motorIn IEEE Electric Ship Technologies Symposium, Philadelphia, Pennsylvania, 25–27 July 2005, pp. 206–216.
MassonP JPienkosJ ELuongoC AScaling up of HTS motor based on trapped flux and flux concentration for large aircraft propulsion. IEEE Trans. Appl. Supercond., 2007, 17(2), 1579–1582.
74.
FrankelD JModel for flux trapping and shielding by tubular superconducting samples in transverse fields, 1979 (Stanford University, Stanford, California, USA).
75.
RadebaughRCryocoolers: the state of the art and recent developments. J. Phys. Condens. Matt., 2009, 21, 9–9.
76.
LandersC LLuceroLHenthornK DHelicopter preliminary design. In No. 3165In 60th Annual Conference of Society of Allied Weight Engineers, Inc., Arlington, Texas, USA, 19–23 May 2001, pp. 1–53.
77.
AIAA. Aerospace design engineers guide, 2003 (American Institute of Aeronautics and Astronautics, Inc, Reston, Virginia).
78.
WenHBaileyWGoddardKAl-MosawiMBeduzCYangYPerformance test of a 100 kW HTS generator operating at 67 K–77 K. IEEE Trans. Appl. Supercond., 2009, 19(3), 1652–1655.
