Apparent Rotation of Runway Sidelines as a Cue to Flare Timing

This paper presents experimental results regarding the timing of the landing flare initiation by airline pilots. From previous research it was hypothesized that pilots use the visual cue theta-dot --which denotes the speed of apparent rotation of the runway side lines-- to decide the proper time to commence the flare. Experiments were carried out in a Boeing 767-300 full flight training simulator, with one Captain and one Junior pilot. Approaches were flown under calm, head, cross- and tail wind conditions, resulting in a variety of approach sink rates, without the demerit of `unnatural\u27visual cues as would be the case with varying glide slopes as usually done in such experiments. Both the proposed theta-dot cue and several other cues suggested in literature are analyzed. Results show significant differences between the pilots with respect to the flare, while the main parameters during glide and at touch down did not. Data of the captain pilot seems to support our hypothesis, although the relatively small sample size and some outliers make it difficult to draw hard conclusions. No clear flare initiation cue could be identified the junior pilot, and his control throughout the flare is less sophisticated as well.Part of "Proceedings of the Asia-Pacific International Symposium on Aerospace Technology (APISAT2009)