INFRA-RED RAYS

New Zealand Herald, Volume LXXII, Issue 22197, 26 August 1935, Page 12

INFRA-RED RAYS

DETECTION OF AIRCRAFT FOUR MILES THROUGH FOG LONDON, Aug. 15 Commander Paul MacNeil has invented an apparatus for detecting aircraft and other moving objects by long infra-red rays as a substitute for searchlights when visibility is poor, says the aeronautical correspondent of the Times. The apparatus may be synchronised with an anti-aircraft gun, enabling a shell to be fired immediately an aeroplane crosses the infra-red beam, thus eliminating the time lag due to tho use of a sound-locator. Moreover, it will be possible to fire at invisible targets, offering a prospect of accurate fire against aircraft hidden by clouds. The invention may be used to differentiate between height and distance, ignoring tho passage of slower objects than those it is intended to detect. It also possesses au amplification factor of 3,000,000 with which ships can bo located 23,000 yards away and aircraft located through fog at a distance of four miles. Commander MacNeil offered tho device to tho War Office in February and later carried out a successful demonstration, but it is stated that tho officials did not evince tho slightest interest. Meanwhile another groat Power offered Commander MacNeil a laboratory in which to develop tho invention. .This offer has not so far been accepted, as the inventor says he hopes either the War Office or the Air Ministry will offer him some encouragement.