A DISNEY mission was a code name for missions where DISNEY rocket-boosted concrete piercing bombs were dropped.
The DISNEY rocket bomb was developed by the Royal Navy for use in penetrating and destroying U-boat and E-boat shelters. It weighed 4,500 pounds (2041 kilograms) and was 14 feet (4,27 meters) long. It was too big to be carried by RAF aircraft so the Yanks were asked to help and in the autumn of 1944, a B-17G was used to test the ability to carry and drop two of the bombs which were carried on wing racks between the fuselage and the inboard engines. With two bombs, weighing 9,000 pounds (4082 kilograms), the B-17G's gross weight was 66,000 pounds (29 937 kilograms) requiring a 4,200 foot (1280 meter) takeoff run. Climb to 20,000 feet (6096 meters) took 40 minutes at 150 mph (241 km/h) indicated air speed.
When the bomb was dropped, it would free-fall until it reached 5,000 feet (1524 meters) and then the rocket motor ignited propelling the missile to a speed of 2400 feet per second (1,636 mph or 2633 km/h) at impact. During tests, the bomb penetrated 20 feet (6,1 meters) of concrete. It was first used operationally on 14 March 1945 by the Eighth Air Force's 92d Bombardment Group (Heavy) against E-boat pens at Ijmuiden, the Netherlands.