Effective Date: 15 June 98

Handling Qualities Testing

Current MIL 8785C Type Testing

Measurement Requirements

The measurements required for handling qualities and stability and control testing are numerous. This section will not attempt to define all measurements which are required because of the multitude of aircraft configurations and types which could exist. Instead, some general direction will be given, and it will be up to the reader to choose the measurements which are required to fit his particular situation.

The measurements used for handling qualities and stability and control testing can be put into four different categories; states, responses, controls, and inputs. Aircraft states refers to the flight conditions/attitude, responses are the disturbances from the steady state, controls are any changes to control surfaces, and inputs are the pilots inputs to the controls. The following paragraphs give some examples of these different types of measurements:

STATES: Airspeed, à, , Mach, Altitude, , í,

RESPONSES: p, q, r, nx, ny, nz

CONTROLS: ëe, ëa, ër, ëF, Fx

INPUTS: Fa, Fr, Fs, ëPS, ëRS, ëPED, PLA, ëT

In addition to the measurements listed above, it is also necessary to know the configuration of the aircraft. This includes status of landing gear, any external stores, and any other change to the aircraft external configuration which is different from the baseline configuration.

All measurements should be recorded at a sample rate which is fast enough to avoid aliasing the frequency of the recorded parameters. A sample rate which is five times the expected maximum frequency of the measured quantity should be sufficient to provide adequate frequency resolution.

Flight notes, although not a measurement, should be kept throughout the entire tests. Handling qualities are mostly qualitative in nature, as such, pilot comments that are made during any test should be written down explicitly by an independent note taker. These comments are especially useful during the post-flight debrief in helping the pilot to recall specific handling quality traits or quirks.