GB1351933A - Camouflage of ships against radar detection - Google Patents

Abstract

1351933 Camouflaging ships against radar detection ELTRO GmbH 16 Aug 1972 [17 Aug 1961] 31570/62 Heading B7S [Also in Division H4] In a ship having surfaces which reflect electromagnetic waves, the cross-sections of the substantially vertical surfaces of the individual components of the ship and of the deck superstructures differ by at least 3 degrees from a right angle in relation to the horizontal surfaces or in relation to the water surface. It is explained that surfaces at right angles reflect radar radiation strongly in the incident direction, whereas if the surfaces differ from a right angle by at least 3 degrees, and preferably between 10 and 20 degrees, the reflection in the incident direction is reduced. The surfaces may be at least partly parabolic in section, and large wall surfaces are preferably sub-divided into individual facette-like areas which are curved concavely along the axes of the surfaces. All surfaces longer than 1 metre in one direction are preferably curvilinear in this direction. The vertical side surfaces of the ship are preferably so shaped that rectilinearly propagated radiation impinging at an angle of 0 to 10 degrees from the horizontal is reflected so that it impinges on the water surface at a distance of 3 to 30 metres from the ship where the water is normally disturbed by the ship's movement. Surfaces participating in multiple reflection may be made of or covered with material which abosrbs electromagnetic waves. Fig. 5, shows a diagrammatic sectional view of the side of a ship and a deck structure, the path of incident radiation and reflected radiation being shown by arrows R and Z respectively. Figs. 7a and 7b show respectively a side elevation and plan of a deck-house.