Experimental Investigation of the Short-Period Requirements of MIL-F-8785C
Report Number: AFWAL TR 86-3109 Volume 1
Author(s): Bailey, Randall E.
Corporate Author(s): ARVI/CALSPAN Advanced Technology Center
Laboratory: Flight Dynamics Laboratory
Date of Publication: 1986-11-01
Pages: 124
Contract: F33615-83-C-3603
DoD Project: 2403
DoD Task: 240305
Identifier: ADA180983
Abstract:
In the current military specification for flying qualities of piloted airplanes (MIL-F-8785C), the short period frequency requirement is expressed as a function of the aircraft's normal acceleration response to angle of attack changes (n/alpha). An investigation of the short period frequency requirements of MIL-F-8785C was performed using the USAF/TIFS in-flight simulator. Thirty-five evaluations of 18 configurations were conducted. The experiment examined the minimum frequency boundary at three values of (n/alpha) for one true airspeed. The experiment included the effects of pilot location and evaluation task. The data indicate that the current requirement is essentially valid. The minimum acceptable frequency boundary may be relaxed, however, when the pilot station is forward of the center of rotation. Also, the phasing between the normal acceleration and pitch rate responses has been shown to be a critical determinant of longitudinal short period flying qualities. The results are analyzed using the equivalent systems methodology. Keywords: Flying qualities; Handling qualities; Flight control system; Control Also anticipation parameter.
Provenance: AFRL/VACA
Author(s): Bailey, Randall E.
Corporate Author(s): ARVI/CALSPAN Advanced Technology Center
Laboratory: Flight Dynamics Laboratory
Date of Publication: 1986-11-01
Pages: 124
Contract: F33615-83-C-3603
DoD Project: 2403
DoD Task: 240305
Identifier: ADA180983
Abstract:
In the current military specification for flying qualities of piloted airplanes (MIL-F-8785C), the short period frequency requirement is expressed as a function of the aircraft's normal acceleration response to angle of attack changes (n/alpha). An investigation of the short period frequency requirements of MIL-F-8785C was performed using the USAF/TIFS in-flight simulator. Thirty-five evaluations of 18 configurations were conducted. The experiment examined the minimum frequency boundary at three values of (n/alpha) for one true airspeed. The experiment included the effects of pilot location and evaluation task. The data indicate that the current requirement is essentially valid. The minimum acceptable frequency boundary may be relaxed, however, when the pilot station is forward of the center of rotation. Also, the phasing between the normal acceleration and pitch rate responses has been shown to be a critical determinant of longitudinal short period flying qualities. The results are analyzed using the equivalent systems methodology. Keywords: Flying qualities; Handling qualities; Flight control system; Control Also anticipation parameter.
Provenance: AFRL/VACA