Fly-by-wire T & E challenge [aircraft test pilot handling compensation]

Systems developers and testers have always assumed that human compensation is measurable, or, at least, that a cognizant and trained tester is able to identify and detect compensation. More than one study conducted at the Wright-Patterson large amplitude multi-mode aerospace research simulator (LAMARS) facility indicates that this is not necessarily true. Test pilots were able to compensate sufficiently to fly and meet defined performance standards on intentionally crippled aircraft flight control designs. These flight control systems were designed to trigger pilot-induced oscillations, but, in most cases, test pilots could compensate sufficiently to prevent pilot-induced oscillations and to control the simulated aircraft. Anecdotally, this points to a colossal deficiency in the test of highly augmented aircraft systems that has been borne out by multiple aircraft accidents in actual aircraft designs: natural pilot compensation is sufficient to allow faulty designs to reach production and operational service while hiding critical handling qualities cliffs that can lead to loss of an aircraft. This observation, if applied across the gamut of human factors experimentation, has vast ramifications for test and evaluation and development of all human interface systems.