Laurie-Lean, D. W.
Abstract:
The longitudinal dynamic response characteristics of a twin-engined
propeller-driven aircraft determined from flight measurements are presented
and compared with predictions based on theoretical studies. Transient
responses to pilot-applied Pulsed notions of the elevator control surfaces
were recorded. The transient data was then converted into frequency response
form by means of the Fourier transformation and compared with predicted
responses calculated from the basic equations of motion of the aircraft.
In particular, detailed experience of the determination of frequency
responses with regard to data sampling frequency and control input shape,
using the Fourier transformation method, was obtained.
Experimentally-determined transfer functions were used for the evaluation
of the stability derivatives that have the greatest effect on the dynamic
response of the aircraft.
Some experience was also obtained with automatic data recording and
processing equipment using magnetic tape, but no satisfactory frequency
responses were obtained using this method. However, with further development
and use of this equipment, the analysis of large quantities of flight data
would be facilitated.