to be refuelled in the air. With jet fighters suffering from short range there was a need for these to be refuelled in the air and several KB-29Ms were modified to use 'probe-and-drogue' systems, in which the refueling hose has a torus-shaped para-drogue attached to the end, and the receiving aircraft has a probe on its nose or wing, which the pilot manoeuvers into the drogue to link the hose. One KB-29M, redesignated YKB-29T, was modified to have another two refueling hoses on its wingtip. It served as the prototype for the KB-50D. The refuelling systems were developed and installed by Flight Refuelling Ltd, at Tarrant Rushton in the United Kingdom. KB-29P Section source: Baugher and National In an effort to improve on the probe-and-drogue system, Boeing developed a rigid flying boom system, which was first used on the KB-29P. The boom was mounted on the aftmost end of the KB-29P, and used a V-tail-like set of control surfaces for stabilization at its far end. With the V-tail-style surfaces, still used on most USAF tanker aircraft in the 21st century, the boom could be manoeuvered by the operator. The flying boom system was selected by SAC as the preferred method for refuelling their bombers and, because of the massive size attained by SAC, it became the most common method for In-Flight Refueling in the USAF and was used on KC-97s and also on modern tankers such as the KC-135 Stratotanker, the KC-10 Extender, and the KC-46 Pegasus. The KB-29P was operated by 420th Air Refueling Squadron based at RAF Sculthorpe Norfolk during the mid-1950s. From 1954 to 1957, the 407th Air Refueling Squadron was based at Great Falls Air Force Base. Later the base name was changed to Malmstrom Air Force Base. Specifications (KB-29P) See also References Sources Swanborough, F.G. and Peter M. Bowers. United States Military Aircraft since 1909. London:Putnam, First edition, 1963. External links Baugher's Encyclopedia of Bombers B-29 Index Page 1940s United States special-purpose aircraft 1940s United States military tanker aircraft KB-29 United States military tanker aircraft Air refueling Four-engined tractor aircraft KB-29 Mid-wing aircraft Four-engined piston aircraft