Heinkel 111 Z "Zwilling"
Heinkel 111 Z "Zwilling": They consisted of two airplanes by the bearing areas was connected. In the coupling place a fifth engine was inserted. Starting from 1942 a small number of these machines to dragging large transport gliders (how the ME 321) built (for lack of other strong airplanes). Thus dangerous "Troika" - dragging procedures with three individual BF (ME) - was replaced 110.