On an aspect of the accident history of aircraft taking off at night

Abstract

An investigation is described into the cause of a series of accidents to aircraft taking off at night; it depends on the fact that the direction of the net reaction on a pilot's body during acceleration is the same as that corresponding to a steady climb. The analysis and a numerical illustration are given in Part I. The results of flight tests designed to check the analysis are summarised in Part II: the results confirm the theoretical findings. It is concluded that the only faculty which can be safely used is that of vision, and this implies the use of instruments throughout the whole of the take-off at night.