K-4

The title of this article is ambiguous. For the aircraft type, see Kalinin K-4 , and for the car model, see Miele K 4 .

K-4 (also: Triplex ) is the Soviet camouflage name for armored glass on fighter aircraft .

The development by the Scientific Experimental Institute of the Aviation Industry began in 1935 and ended in 1939 with the consultation of the most famous Soviet physicist Abram Fyodorovich Joffe and his colleague Anatoli Petrovich Alexandrov . The development of bulletproof glass was a military secret in all countries at the time .

The laminated glass consisted of a total of three layers, with a protective layer of toughened glass called Stalinit stuck to a 40 mm thick Plexiglas pane and another colorless pane on top . The protective screen was not made from one piece, but consisted of individual curved disks, which were called "tablets". The glass could withstand machine-gun fire and projectile splinters, but many small cracks formed.

The first aircraft type equipped with it was the Ilyushin Il-2 . By the end of the war, all types of Soviet aircraft could be equipped with armored glass.

literature

• Wilfried Copenhagen : Lexicon Soviet Aviation. Transpress, Berlin 1986, ISBN 3-344-00005-5 , p. 111 f.