IOCU 5MP 12 AZON BOMB SECRET. A B-24 bomber flying a mission. According to this photograph's header, it may be carrying an AZON.
"AZON (AZimuth ONly) was one of the world's first smart bombs, deployed by the Allies and contemporary with the German Fritz X.
Officially designated VB-1 (Vertical Bomb), it was invented by Major Henry J. Rand and Thomas J. O'Donnell during the latter stages of World War II, as the answer to the difficult problem of destroying the narrow wooden bridges that supported much of the Burma Railway.
AZON was essentially a 1,000 lb (450 kg) bomb with a radio controlled tail fin allowing adjustment of the vertical trajectory in two planes, making basically a guided fall. There were gyroscopes mounted in the bomb to stabilise it, and a radio control system, which had about three minutes of battery life, long enough to guide it from a 5,000 foot (1,500 m) drop height. On the tail of the bomb was a 600,000 candela flare, to enable the pilot to observe it from the control aircraft. It was dropped from a modified B-24 Liberator. Only ten crews, of the 458th Heavy Bombardment group based at Horsham St Faith, were trained to drop the device.
AZON crews famously destroyed Bridge 277, the Bridge on the River Kwai, although they used four 1,000 lb conventional bombs from tree-top height, making four direct hits and destroying one concrete pier, along with two of the spans."
Courtesy of Wikipedia