Boundary-Escape Tracking: A New Conception of Hazardous PIO

Abstract

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Boundary Avoidance Tracking: A New Pilot Tracking Model

“…Numerous patterns were noted while checking sensitivities to variations in the model. 7 Confirmation of these patterns through data analysis awaits further work.…”

Investigations on boundary avoidance tracking and pilot inceptor workload

“…This behaviour is referred to as point tracking. In 2004, Bill Gray introduced a new theory which suggests that there are situations when the pilot abandons the point tracking task in favour of boundary avoidance tracking (BAT) [2,3], a control action based on the avoidance of unfavourable or even dangerous conditions like stall, over-g or ground impact. The concept was mainly based on anecdotal evidence he experienced during his career as a test pilot.…”

“…Gray first introduced his theory in 2004 [2,3]. The expressions ''Boundary Escape Tracking'', ''Boundary Avoidance Tracking'' and ''Point Tracking'' were introduced and initial considerations were given to a suitable BAT pilot model.…”

“…The BAT model, therefore, implies a switching behaviour between point tracking and BAT. It is hypothesized that the pilot intuitively switches to BAT when the BAT input exceeds the point tracking input and vice versa [2,3].…”

“…If the hypothesis is true that many PIOs are based on BAT [2], current flight test methods do not cover the whole range of the pilot's control behaviour and potential PIO problems may not be discovered during flight test. This is why conventional tracking tasks have been altered to create a task which is boundary-dependent [2,3,[6][7][8].…”