The Theory of Visual Judgments in Motion and its Application to the Design of Landing Aids for Aircraft

Abstract

This paper is intended to bring the theory of the visual aids up to date, and to discuss various practical methods of increasing the safety of the approach and landing operation. Arguments are put forward to show that the guidance in the vertical plane needs to be improved, particularly in visibilities somewhat above the limiting visibility, and a new form of angle of approach indicator is described, which promises to achieve this result. The beam spreads of the approach lights should be increased, and fittings for providing guidance for circling approaches should be developed. The British design of flush-type runway light has proved! satisfactory in actual operations, and as a result, landing mats have now become practicable, even on existing runways.

Optic Flow: A History

“…In 1957, Calvert further expanded on how displacement, track heading and track curvature—or “where [one] is at any moment, where [one] is going at that moment, and … where [one] will be going a few moments later” ( Calvert, 1957a , p. 272)—are perceived by the pilot in the horizontal and vertical planes. As we have seen above when Calvert discussed “[giving the zero point] a velocity towards [the aim point]” ( 1954 , p. 244), previously, he did not show an appreciation for the fact that a laminar motion is added to the visual motion pattern when the observer's orientation changes, such as when traveling along a curved path.…”

“…Calvert. Calvert too receives a fair number of citations on his major papers ( Calvert, 1954 , 1957a ; and the apparently lesser known, Calvert, 1950 ). As far as I am aware however, with the exception of Beall and Loomis ( 1996 , 1997 ) who discussed Calvert's theory of visual control of aircraft, all these citations are tangential and no other text examines Calvert's contributions in detail.…”

Visual Spatial Disorientation: Re-Visiting the Black Hole Illusion

“…Calvert (9) referred to the BH effect occurring the last 23 m above the ground. Kraft (31) There is yet no consistent explanation of and no agreed upon distance when and why the BHI may occur.…”

Terrain Orientation Theory for a Visual Approach to Landing

“…Many studies have made reference to the black hole illusion from a variety of distances. Calvert (1957) referred to the black hole effect occurring the last 23 m above the ground. Kraft (1978) started subjects at 32 km and stopped 7.2 km from the runway because this point was 1.6 km prior and 76 m above where ground motion cues would assist with altitude control (p.2).…”

“…Consequently, it is difficult to understand visual illusions when a solid theory is lacking for organizational perception during normal, nonillusory conditions. More specifically, the featureless terrain illusion or black hole approach has been described in aviation research for many years and still continues to contribute to aircraft accidents (Calvert, 1957;Kraft, 1978;Palmisano & Gillam, 2005;Perrone, 1984).…”