The SB-17, also known as the B-17H, was developed as a variant of the iconic B-17 Flying Fortress and was primarily designed for air-sea rescue missions, gaining the nickname “Dumbo†due to its rescue role.
Heavy bombers, specifically modified to manage the lifeboat’s external load, carried this robust airborne lifeboat.
Intended for parachute drop during Dumbo missions, the SB-17 would drop a A-1 rescue boat, which was aimed to land near downed airmen.
Approximately 130 B-17Gs underwent modifications for USAAF air-sea rescue missions, which included equipping them with an airborne lifeboat.
A U.S. Coast Guard Boeing PB-1G Flying Fortress search and rescue plane in flight. The USCG used 18 former USAAF SB-17G from 1945 to 1959.
The Higgins A-1 lifeboat was to be dropped by an SB-17 traveling at an airspeed of 120 miles per hour. The yellow-painted vessel was supplied with enough food, water and clothing for 12 survivors to last for about 20 days in the ocean. It was provided with sails kept relatively small so that inexpert operators could use them.
The SB-29 dropped the A3 boat as seen in the second picture.
The success of the B-17H later referred to as the SB-17 Dumbo, prompted experimentation with a similar air-sea rescue aircraft based on the B-29 as early as 1944. The Superfortress’s extended range, increased lift capacity, and advanced features were all deemed improvements over the SB-17’s capabilities.
In 1949, a series of conversions for a select number of SB-29 aircraft commenced. According to recent research by Robert A. Mann, 25 such aircraft were primarily converted at Tinker Air Force Base.