A project of the “Synchropter” type high-speed helicopter with pushing air propeller

Аuthors

Nikitin S. O.^*, Makeev P. V.^**

Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia

*e-mail: luber6785@yandex.ru
**e-mail: vaultcity13@gmail.com

Abstract

Due to the helicopters ability to perform vertical take-off and landing, as well as effective operation while hover mode, they became indispensable practically in all regions of the world. With that, the requirements for the helicopters flight performance enhancement become ever more acute, primarily concerning the increase in speed and range.

Currently, a number of rotary-winged aircraft structures of vertical take-off and landing, realizing increase in speed and flight range, are under development and in some cases at the stage of testing and batch production in leading world countries. There is a number of concepts and technical solutions, mainly in the field of aerodynamics, allowing increase a helicopter cruising speed. In this regard, the exploratory research and these projects implementation development are highly relevant.

The presented work is devoted to creation of a project of a perspective passenger high-speed aircraft with vertical take-off and landing based on a helicopter with intermeshing rotors and a pushing air propeller.

The project employs a set of the following technical solutions:

-    The blades rotational speed reduction (from 220 to 180 mps) as the flight speed increase; special arrow­shaped tips setting on the blades to reduce to zero the probability of a wave crisis on the advancing blades with flight speed increasing;

-    Balancing the unbalanced lateral tilting moments on the two rotors of a “synchropter” scheme, rotating in opposite directions;

-     Application of rotors with elastic torsion sleeves;

-    Application of a system of the blades individual control to prevent the flow disruption on the retreating blades;

-    The aircraft fuselage layout with account for the specifics of the scheme with low frontal resistance at near-zero angles of attack;

-    Application of a propulsion propeller with maximum efficiency in operating conditions.

The capabilities of modern computer-aided design technologies were demonstrated while the project developing. The main emphasis is made on the aircraft dynamic designing with implementation of modern tendencies of the high-speed helicopters development. The main limitations and possible ways for the helicopter speed increase implementation were considered. The article presents the computational results of aerodynamic characteristics with account for the decisions made.

The developed project has the following characteristics: the take-off weight of 6500 kg, payload mass of 1000 kg, maximum speed of 420 km / h, static ceiling of 4700 m, dynamic ceiling of 5600 m, and flight range of 1228 km.

The obtained results indicate the achievement of indicators close to the modern world level, demonstrated on similar developed helicopters.

The developed project has prospects for further flight performance improvement by improving the‘ aerodynamic characteristics of the fuselage, propellers, as well as exploiting more fully the capabilities of the individual blade control system.

Keywords:

flying vehicle design, perspective highspeed helicopter, synchropter type main rotor, pushing propeller, aerodynamic design, numerical modeling, flight performance

References

1. Tishchenko M.N., Artamonov B.L. Trudy MAI, 2012, no. 55. URL: http://tmdymai.ru/eng/published.php?ID=30115

2. Mikheev S.V. Puti sovershenstvovaniya vintokrylykh letatel’nykh apparatov (Ways of rotorcraft improving), Moscow, MAI, 2006, 63 p.

3. Ignatkin Yu.M., Makeev P.V., Shomov A.I. Aerodinamicheskie skhemy vintokrylykh letatel’nykh apparatov (Rotorcraft configuration aerodynamic), Moscow, MAI, 2018, 88 p.

4. Leishman J.G. Principles of Helicopter Aerodynamics. Cambridge University Press, 2006, 864 p.

5. Johnson W. Rotorcraft aeromechanics. Cambridge University Press, 2013, 944 p.

6. Jonhson W. Helicopter theory. Courier Dover Publications, 1994, 1120 p.

7. Nikitin S.O., Ignatkin Yu.M., Makeev P.V. 16-ya Mezhdunarodnaya konferentsiya “Aviatsiya i kosmonavtika – 2017”. Sbornik tezisov dokladov, Moscow, Lyuksor, 2017, p. 50.

8. Kruchinin M.M., Artamonov B.L. Analysis of hinge moments occurring on helicopter main rotor blades. Aerospace MAI Journal, 2016, vol. 23, no. 3, pp. 15-20.

9. Bell V-280 Valor Specifications, http://www.bellflight.com/military/bell-v-280#sectionSpecs

10. Bell Helicopter Achieves First Flight of V-280 Valor, http://www.collectivemag.com/bell-helicopter-achieves- first-flight-v-280-valor/

11. Airbus Clean Sky 2, The future of high-speed rotorcraft, https://www.airbus.com/innovation/clean-sky-2.html

12. American Helicopter Society paper. The ABC Rotor – A Historical Perspective, Robert K. Burgess. Presented at the 60th AHS Annual Forum, Baltimore, MD, June, 2004

13. S-97 RAIDER® Demonstrator, https://www.lockheedmartin.com/en-us/products/s-97-raider-helicopter.html

14. Rotorcraft Report: DARPA Pursues Disc Rotor Development, https://www.rotorandwing.com/2008/10/01/rotorcraft-report-darpa-pursues-disc-rotor-development/

15. Kalinin D.V., Kalinin Y.V. Two-stage transmission scheme design for perspective helicopter. Aerospace MAI Journal, 2016, vol. 23, no. 1, pp. 38-46.

16. Animitsa V.A., Borisov E.A., Kritskii B.S., Mirgazov R.M. Trudy MAI, 2016, no. 85. URL: http://trudymai.ru/eng/published.php?ID=65452

17. META: Active Rotor Control using a Multiple Swashplate System, https://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10660/1147_read-4496/#/gallery/6881

18. Basov K. CATIA V5. Geometricheskoe modelirovanie (CATIA V5. Geometric modeling), St. Petersburg, DMK Press, 2008, 272 p.

19. ANSYSFLUENT 6.3. Theory Manual. 2005. Fluent Inc. Central Source Park, 10 Cavendish Court, Lebanon, NH 03766, USA. http://www.fluent.com

20. Tishchenko M.N. Vybor parametrov vertoleta na nachal’noi stadii proektirovaniya (The choice of parameters of the helicopter at the initial stage of design), Moscow, MAI, 2011, 121 p.

21. Shaidakov V.I., Troshin I.S., Ignatkin Yu.M., Artamonov B.L. Algoritmy i programmy raschetov v zadachakh dinamiki vertoletov (Algorithms and computing programs in problems of helicopters dynamics), Moscow, MAI, 1984, 53 p.

22. Ignatkin Yu.M., Makeev P.V., Grevtsov B.S., Shomov A.I. A nonlinear blade vortex propeller theory and its applications to estimate aerodynamic characteristics for helicopter main rotor and anti-torque rotor. Aerospace MAI Journal, 2009, vol. 16, no. 5, pp. 24-31.