The development of large lightweight airframes has resulted in what used to be high frequency
structural dynamics entering the low frequency range associated with an aircraft’s rigid body dynamics.
This has led to the potential of adverse interactions between the aeroelastic effects and
flight control, especially unwanted when incidents involving failures or extreme atmospheric disturbances
occur. Moreover, the pilot’s response in such circumstances may not be reproducible
in simulators and unique to the incident. The research described in this thesis describes the
development of a pilot model suitable for the investigation of the effects of aeroelasticity on
manual control and the study of the resulting airframe loads. After a review of the state-ofthe-
art in pilot modelling an experimental approach involving desktop based pilot-in-the-loop
simulation was adopted together with an optimal control based control-theoretic pilot model.
The experiments allowed the investigation of manual control with a nonlinear flight control
system and the derivation of parameter bounds for single-input-single-output pilot models. It
was found that pilots could introduce variations of around 15 dB at the resonant frequency
of the open loop pilot-vehicle-system. Sensory models suitable for the simulation of spatial
disorientation effects were developed together with biomechanical models necessary to capture
biodynamic feedthrough effects. A detailed derivation and method for the application of the
modified optimal control pilot model, used to generate pilot control action, has also been shown
in the contexts of pilot-model-in-the-loop simulations of scenarios involving an aileron failure
and a gust encounter. It was found that manual control action particularly exacerbated horizontal
tailplane internal loads relative to the limit loads envelope. Although comparisons with
digital flight data recordings of an actual gust encounter showed a satisfactory reproduction and
highlighted the adverse affects of fuselage flexibility on manual control, it also pointed towards
the need for more incident data to validate such simulations.
| Identifer | oai:union.ndltd.org:CRANFIELD1/oai:dspace.lib.cranfield.ac.uk:1826/10388 |
| Date | 01 1900 |
| Creators | Lone, M. Mudassir |
| Contributors | Cooke, A. K. |
| Publisher | Cranfield University |
| Source Sets | CRANFIELD1 |
| Language | English |
| Detected Language | English |
| Type | Thesis or dissertation, Doctoral, PhD |
| Rights | © Cranfield University, 2013. All rights reserved. No part of this publication may be reproduced without the written permission of the copyright holder. |
Page generated in 0.0016 seconds