The "killing zone" revisited: serial nonlinearities predict general aviation accident rates from pilot total flight hours.

Background: Is there a "killing zone" (Craig, 2001)-a range of pilot flight time over which general aviation (GA) pilots are at greatest risk? More broadly, can we predict accident rates, given a pilot's total flight hours (TFH)? These questions interest pilots, aviation policy makers, insurance underwriters, and researchers alike. Most GA research studies implicitly assume that accident rates are linearly related to TFH, but that relation may actually be multiply nonlinear. This work explores the ability of serial nonlinear modeling functions to predict GA accident rates from noisy rate data binned by TFH.

Testing a multidimensional nonveridical aircraft collision avoidance system.

Objective: This study explores operators' ability to use a multidimensional, nonveridical control display.

Background: Veridical displays represent realistic scenes. State space displays represent nonveridical n-dimensional information based on informative coordinate axes plus variable features such as color and shading.

Clockwise and counterclockwise rotating shifts: effects on temperature and neuroendocrine measures.

Introduction: Most researchers suggest that shift rotation in a clockwise (CW) direction produces less disruption of circadian rhythms than rotations in a counterclockwise (CCW) direction. This is based on extrapolation from quasi-experimental studies of shift workers and research on the effects of jet lag that indicate that westward travel results in less disruption of circadian rhythms.

Methods: The effect of direction of rotation on cortisol, melatonin, and rectal temperature was examined in participants randomly assigned to either a CW (n = 14) or CCW (n = 14) shift rotation.