Boeing KB-29M refuelling a Republic EF-84E Thunderjet, 2 September 1950

The Boeing KB-29M was a tanker version of the B-29 bomber used for refuelling trials. There was just one Republic EF-84E Thunderjet converted for the trials.

The KB-29M was fitted with a single trailing hose unit developed by Flight Refuelling Ltd. The EF-84E was fitted with a probe which could engage with the hose, the so called ‘probe and drogue’ method of air-to-air refuelling. Trials began in 1949 but, despite their success, the United States Air Force adopted the flying boom as its preferred method of refuelling in flight.