Page 78 - Marutas of Unit 731

“U Bomb—e 30kg U bomb was designed to spray liquids by means of

compressed air at a predetermined altitude. e bomb had a det achable nose

covering a spray head. It was equipped with an impact nose fuze, a delay tail

fuze and a self-timing tail mechanism which operated upon release from the

airplane. Action of the self-timer allowed the central burster tube to move

for ward separating the detachable nose from the spray head. e for ward
motion of the central burster tube also caused release of the compressed air

with spraying of the bomb itself exploded. Only 20 rounds of this bomb

were manufactured, Ishii said, and no eld exper iments were conducted

aside from tests to determine bomb function. Because of leakage of the

contents, defective fuzes, inaccurate timing mechanism, and because of its
complicated structure the U bomb was not considered worthy of further

development and was discarded.”