Small helicopter flight test report

AbstractFor a broad range of applications, flight mechanics simulator models have to accurately predict the aircraft dynamics. However, the development and improvement of such models is a difficult and time consuming process. This is especially true for helicopters. In this paper, two rapidly applicable and implementable methods to derive linear input filters that improve the simulator model are presented. The first method is based on model inversion, the second on feedback control. Both methods are evaluated in the time domain, compared to recorded helicopter flight test data, and assessed based on root mean square errors and the Qualification Test Guide bounds. The best results were achieved when using the first method.

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Rotor Downwash Velocities about the UH-1M Helicopter - Flight Test Measurements and Theoretical Calculations

10.21236/ada008965 ◽

1975 ◽

Author(s):

B. Z. Jenkins ◽

A. S. Marks

Keyword(s):

Theoretical Calculations ◽

Flight Test ◽

Helicopter Flight

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Guided Drogue Flight Test Report

10.21236/ada049164 ◽

1977 ◽

Cited By ~ 1

Author(s):

J. A. Ellsworth ◽

W. R. Fox ◽

D. E. Lovendahl ◽

J. E. Moore

Keyword(s):

Flight Test ◽

Test Report

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Distributed Turbulence Model with Rigorous Spatial Cross-Correlation for Simulation of Helicopter Flight in Atmospheric Turbulence

Journal of the American Helicopter Society ◽

10.4050/jahs.64.042011 ◽

2019 ◽

Vol 64 (4) ◽

pp. 1-13

Author(s):

Honglei Ji ◽

Renliang Chen ◽

Pan Li

Keyword(s):

Atmospheric Turbulence ◽

Turbulence Model ◽

Cross Correlation ◽

Turbulence Models ◽

Flight Test ◽

Longitudinal Direction ◽

Flight Simulation ◽

Quality Analysis ◽

Frequency Range ◽

Helicopter Flight

This paper presents a distributed turbulence model with rigorous spatial cross-correlation for helicopter flight simulation in atmospheric turbulence and for future handling-quality analysis. First, digital filters with longitudinal correlations of the von Kármán turbulence are developed to generate discrete turbulence velocity components. Meanwhile, transverse turbulence correlations are considered by relating the filters in different positions with mathematically rigorous spatial cross-correlation. Then, the distributions of the related filters on the transverse plane in front of helicopter and their velocity components in the longitudinal direction of airspeed, as well as turbulence models of helicopter aerodynamic surfaces, are established. Finally, a flight dynamics model coupled with the turbulence model is developed and validated against the flight-test data. The proposed model can achieve accurate real-time simulations of helicopter response to atmospheric turbulence in the frequency range of interest of handling qualities. The effect of transverse turbulence correlations on helicopter frequency response is also analyzed. The results show that the simulation model regardless of transverse turbulence correlations would aggravate the "rotor-to-body attenuation" effect of the main rotor and therefore underpredict the helicopter roll, pitch, and heave rate responses to atmospheric turbulence in the frequency range of interest.

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Part 2 Some Features of Flight Testing on the Fairey F.D.2 Leading up to the Successful Attempt on the World Speed Record and Subsequent Flying

Journal of the Royal Aeronautical Society ◽

10.1017/s036839310012838x ◽

1957 ◽

Vol 61 (559) ◽

pp. 447-466

Author(s):

L. P. Twiss

Keyword(s):

Flight Test ◽

Development Programme ◽

Test Report ◽

Handling Characteristics ◽

Successful Attempt ◽

The World ◽

Air Speed ◽

Opening Paragraph ◽

Interesting Development ◽

Engineering Personnel

The opening paragraph in my first Flight Test Report after the initial flight of the Fairey Delta 2 still rings very true today:—“This aircraft shews every promise of being a very pleasant flying machine. Soon after take-off, I had confidence in the handling characteristics, and I should like to congratulate all the design and engineering personnel who made this possible.”This great day was the 6th October 1954, at Boscombe Down, and was the start of an intensely interesting development programme—not without its setbacks and excitements—which was highlighted last March by the gaining of the World's Absolute Air Speed Record for Britain. The early flights followed the pattern of most prototype aircraft and, but for an unfortunate setback on the fourteenth flight, went very smoothly.

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Helicopter flight simulation trim in the coordinated turn with the hybrid genetic algorithm

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410017745899 ◽

2017 ◽

Vol 233 (3) ◽

pp. 1159-1168 ◽

Cited By ~ 1

Author(s):

Wei Wang ◽

Dongsheng Li ◽

Chun Liu

Keyword(s):

Genetic Algorithm ◽

Hybrid Genetic Algorithm ◽

Flight Test ◽

Flight Simulation ◽

Control Vector ◽

Experimental Platform ◽

Helicopter Flight ◽

Quasi Newton ◽

General Method ◽

Good Agreement

Helicopter trim models are multivariate nonlinear equations and it is difficult to determine these initial trim points comparable to flight conditions. To solve this question, a hybrid genetic algorithm is presented in this paper, that combines the quick convergence ability of the quasi-Newton method and the advantages of genetic algorithm, such as global convergence. The trim control vector and the constraint conditions were established in the coordinated-turn based on the helicopter flight dynamic model. The coordinated turn flight of a UH-60 A helicopter was taken as an example to simulate on the experimental platform. Comparisons were made between the trim results and flight test data and there is a good agreement among them, and the efficiency of the algorithm presented is verified. It is a general method that can be applied to trim the helicopter of different flight conditions.

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