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On aircraft flight performance in a perturbed atmosphere

Published online by Cambridge University Press:  04 July 2016

L. M. B. C. Campos
L. M. B. C. Campos*
Affiliation:
Instituto Superior Técnico, Lisbon, Portugal
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Summary

We consider the effect of atmospheric disturbances, such as wind, shears, turbulence, wakes and downflows, on aircraft performance (section 1), recalling the minimum of aerodynamics (section 2) necessary for the calculation of the effects on flight mechanics. For example, it is shown (section 3) that the relative lift change, due to wind, shear or both, coincides with the disturbance intensity G, defined as the instantaneous vertical acceleration, measured in g's, that an aircraft will experience as a consequence of atmospheric disturbances, assuming constant velocity and attitude. The disturbance intensity is a measure of the total force that the atmospheric disturbance can exert on the aircraft; this force may cause changes in normal acceleration, flight velocity and angle-of-attack, either isolated (section 5) or combined (section 6), in straight and level flight; in the case of a horizontal turn (section 7), the disturbance intensity specifies the changes in instantaneous turn rate, velocity, radius (section 8), acceleration and bank angle (section 9) due to atmospheric perturbations, and their cumulative effect over time in (section 10) deforming and displacing trajectories. These effects (section 11) are quantified by formulas and illustrated in graphics, and we indicate throughout the flight mechanical consequences of disturbances with the critical intensities G1 = — 0·17 and G2 = — 0·42; these are the disturbance intensities which, if uncompensated, would be just enough to cause an aircraft to stall (section 4) respectively at unstick on take-off and on approach to land. We conclude (section 12) with a discussion of the use of the disturbance intensity as a parameter in the reduction and analysis of flight data.

Type
Research Article
Information
The Aeronautical Journal , Volume 90 , Issue 898 , October 1986 , pp. 302 - 312
Copyright
Copyright © Royal Aeronautical Society 1986 

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References

1. Lanchester, F. W. Aerodonetics. Constable, 1945.Google Scholar
2. Von Mises, R. Theory of Flight. McGraw-Hill 1945, Dover 1959.Google Scholar
3. Duncan, W. J. The Principles of Control and Stability of Aircraft. Cambridge UP, 1952.Google Scholar
4. Perkins, E. W. and Hage, L. Airplane Performance, Stability and Control. Chapman and Hall, 1956.Google Scholar
5. George, L. and Vernet, J. F. La Méchanique du Vol. Béranger, 1960.Google Scholar
6. Lecomte, P. Micanique du Vol. Dunod, 1962.Google Scholar
7. Babister, A. W. Aircraft Stability and Control. Oxford UP, 1961.Google Scholar
8. Babister, A. W. Aircraft Dynamic Stability and Response. Pergamon, 1980.Google Scholar
9. Etkin, B. Dynamics of Atmospheric Flight. Wiley, 1972.Google Scholar
10. Milne-Thomson, L. M. Theoretical Aerodynamics. MacMillan 1958, Dover 1973.Google Scholar
11. Campos, L. M. B. C. On the influence of atmospheric disturbances on aircraft aerodynamics. The Aeronautical Journal. Paper 1085, June/July 1984, 257–264.Google Scholar
12. Etkin, B. Turning in a wind. Eng J (Can), 1945.Google Scholar
13. Etkin, B. Effect of wind gradient on glide and climb. J Aeron Sci, 1947.Google Scholar
14. Pinsker, W. J. and Jones, J. G.. Possible losses of airspeed during turning manoeuvres in gusty air, Aeron Res Counc, 1972, RM, 3672.Google Scholar
15. Bochis, V. Dynamics of an aircraft in a windshear of arbitrary direction. J Guidance, 7, 615–619.Google Scholar
16. Frost, W., Cosby, B. and Camp, D. W. Flight through thunderstorm outflows. AIAA Journ Aircraft, 16, 11–15.Google Scholar
17. Etkin, B. The turbulent wind and its effect on flight. Univ Toronto Aerosp Dep, Rev 44, 1980.Google Scholar
18. Sweezy, W. B., Moninger, W. R. and Strauch, R. G. Simulation of radar-measured Doppler velocity profiles in low-level wind shear. FAA, RD-78-46, 1977.Google Scholar
19. Woodfield, A. A. and Vaughan, J. M. Using an airborne DO2 CW-laser for free stream airspeed and windshear measurements. AGARD, CP-373, 22, 1984.Google Scholar
20. Vorsmann, P. An on-line realisation for precise wind vector measurements on board the Do28 research aircraft. Int Cone Aeron Sci, Paper 84-5.10.1.Google Scholar
21. Woodfield, A. A. and Woods, J. F. Wind shear from head wind measurements on British Airways B747-236 aircraft. RAE, TM-409, 1981.Google Scholar
22. Gerlach, O. H., Van de Moesdijk, G. A. J. and Van Der Vaart, J. C. Progress in the mathematical modelling flight in turbulence. AGARD CP-140, 1973.Google Scholar
23. Van De Moesdik, G. A. J. The description of patchy atmospheric turbulence, based on a non-Gaussian simulation technique. Delft Univ Aerosp Dep, Rep VTH-192, 1975.Google Scholar
24. Jones, J. G. Modelling of gusts and wind shear for aircraft assessment and certification. RAE, 1976.Google Scholar
25. Zhu, S. and Etkin, B. A Fluid-dynamic model of a downburst. Univ Toronto Aerosp Dep, Rep, 271, 1983.Google Scholar
26. Tomlinson, B. N. Developments in the simulation of atmospheric turbulence. AGARD CP-198, 1975.Google Scholar
27. Kaufmann, B. On the interaction of atmospheric turbulence and unsteady lift. AGARD CP-, 1985.Google Scholar
28. Diederich, F. W. The response of an airplane to random atmospheric disturbances. NACA TN-3910, 1957.Google Scholar
29. Brockhaus, R. and Wuest, P. Open-loop compensation of wind-shear effects in low level flight. AGARD CP-240, 19, 1978.Google Scholar
30. Van Der Vaart, J. C. Aircraft response to wind shears and down draughts. AGARD CP-260, 16, 1979.Google Scholar
31. Parks, E. K., Wingrove, R. C, Bach, R. E. and Mehta, R. S. Identification of vortex-induced clear air turbulence using airline flight records. AIAA Journ Aircraft, 1985, 22, 124.Google Scholar
32. Etkin, B. and Zhu, S. Control logic for landing-abort autopilot mode. Univ Toronto Aerosp Dep. Rep 258, 1982.Google Scholar
33. Cavalcanti, S. G. Critical conditions for the automatic control of landing from decision height in variable winds. Univ Toronto Aerosp Dep, Rep 284, 1984.Google Scholar
34. Schanzer, G. The effect of gusts and windshear for automatic STOL approach and landing. AGARD CP-140, 1973.Google Scholar
35. Reid, L. D., Markov, A. B. and Graf, W. O. The application of techniques for predicting STOL aircraft response to wind shear and turbulence during the landing approach. Univ Toronto Aerosp Dep, Rep 215, 1977.Google Scholar
36. Bray, R. S. A method for three-dimensional modelling of wind-shear environments for flight simulator applications. NASA TM-85969, 1984.Google Scholar
37. Kurylowich, G. A method for assessing the impact of wake vortices on USAF operations, AF Flight Dynamics Lab, AFFDL-TR-79 3060, 1979.Google Scholar