After the Invasion of Poland in 1939 Świątecki evacuated to Hungary and via Yugoslavia and Italy to France (Paris) where he worked as engineer in military industry.
Then, when France collapsed in June 1940, he escaped again, with his family, travelling to North Africa and then by ship to England.
The slip device was modified for use in the Lancasters of 9, 12 and 617 Squadrons of the Royal Air Force for the use of the Tallboy and Grand Slam giant aerial bombs.
The Ministry claimed the device was invented at the Royal Aircraft Establishment, Farnborough and developed by Vickers Armstrongs.
In 1943, an updated version of Świątecki invention was created by Jerzy Rudlicki for the American Boeing B-17 Flying Fortress.