Predictive Landing Guidance in Synthetic Vision Displays

Abstract

Pilot manual path-following performance with synthetic vision displays can be improved with predictive guidance symbols. Little is known, however, on how these predictive guidance concepts can be applied to the landing flare maneuver. This paper discusses the applicability of 3D predictive guidance in synthetic vision displays during the final phase of the landing. Two types of predictive guidance were examined, the Flight-Path Predictor that indicates the aircraft's future position a certain time ahead, and the Flight Trajectory Predictor that presents the future trajectory by interpolating a number of sequential predicted positions. A theoretical investigation and an offline simulation were used to optimize the two guidance laws for the manual landing task. A pilot-in-the-loop experiment, conducted in a moving-base flight simulator, indicated that both predictive guidance types investigated support pilots in manual control. The pilot's ability to determine the correct flare initiation time is improved, and becomes comparable to timing the flare with a more realistic synthetic vision display with textured surfaces. Even though the flare initiation timing was improved by the addition of predictive guidance, the control of the flare after its initiation was not sufficiently supported. As a result, no noticeable improvement in landing performance was found.

The Effect of Synthetic Vision Enhancements on Landing Flare Performance

“…Pilot gain behavior was constant after 3 seconds of FPP prediction time and the optimum time was 5 seconds in relation to performance. 10 It must be noted that with 5 seconds of FPP time, pilots had to judge when to flare by themselves.…”

“…9,10 This strategy assumes a pilot can perceive the TTC accurately in an unbiased manner when the aircraft's main gear will contact the runway with no action taken. 8 Mathematically, TTC is defined as the distance between the pilot's eye and the aiming point divided by the closing velocity.…”

Predictive Landing Guidance in Synthetic Vision Displays

“…It is assumed that the two most important subjective measures that determine the landing performance are the runway consumption until touchdown d rw and the descent velocity at touchdown h td . Therefore, it is stated that the landing maneuver is successful when these two measures are within the following limits [22]:…”

“…Still, the highfrequency elevator deflections 'hides' the exact flare initiation time. Therefore, a Moving Average Filter (MAF) was applied to provide a reliable solution [22]. First, the original elevator control 'signal' is processed by a MAF with an interval length that equals the period of the short period eigenfrequency (Fig.…”

Trigger event – a key factor in adverse Aircraft/Rotorcraft Pilot Couplings

“…The quantification of simulator fidelity have been developed using an adaptive pilot model in acceleration/deceleration manoeuvre [43]. Based on tau-guidance strategy, reference [44] investigates the applicability of 3D prediction guidance in Synthetic Vision Display during the final phase of landing through time-tocontact and tau-coupling techniques. Reference [45] investigates change of rate of width runway angle (in respect with pilot eye) through mathematical analysis using data obtained from flight simulator landings.…”