Boeing KB - 29 The Boeing KB - 29 was a modified Boeing B - 29 Superfortress for air refueling needs by the USAF . Two primary versions were developed and produced : KB - 29M and KB - 29P . The 509th and 43d Air Refueling Squadrons ( Walker AFB , NM and Davis - Monthan AFB , AZ respectively ) were created in 1948 to operate the KB - 29M tankers . The 303d Bombardment Wing at Davis - Monthan AFB flew B - 29s and KB - 29s from 1951 to 1953 that provided training for strategic bombardment and air refueling operations to meet SAC ' s global commitments . Deployed at Sidi Slimane AB , French Morocco , Oct 5 - Nov 6 , 1952 . Variants . KB - 29M . The B - 29 played an important role in developing the effective use of aerial refueling during the late 1940s . The first aircraft involved in this programme were the KB - 29M tanker and B - 29MR receiver . At first , a grappling system , known as the looped hose method , was used ; the tanker would formate behind , above and to the left of the receiver . It would then unreel a hauling cable attached to a 55 lb weight ( to make it dangle near vertically ) . The receiver would trail a hauling cable ending in a drag cone ( to make this trail near horizontally ) and a grapnel . With both cables trailed , the tanker would cross to the right of the receiver so the two cables snagged each other . With cables snagged , the tanker hauled both into its fuselage where the receiver ' s cable was connected to the tanker ' s hose . This was then hauled into the receiver . After connecting with internal fuel compartments pumping would begin . When the receiver was full the process was reversed allowing the tanker to recover its hose and the receiver its hauling cable . While this system was clumsy , it was often used in the late 1940s before a better system was developed . It was most notably used to refuel the " Lucky Lady II " during her famous circumnavigation of the globe in 1949 . The ability of the USAF to circumnavigate the globe demonstrated that its bombers could strike at any target . This helped sway the argument as to whether the USAF or US Navy should provide the US ' s nuclear delivery capability . The USAF won with the consequential massive expansion of the USAF ' s Strategic Air Command and cancellation of the US Navy ' s super carriers . The looped hose method was only of use with large multi crew planes since crew members were required to assist in the hauling in . A modified method known as the probe and drogue system was developed to allow single seat aircraft 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 . 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 had two small wings . With these wings , 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 KB - 50s and KC - 97s and also on modern tankers such as the KC - 135 Stratotanker and KC - 10 Extender . The KB - 29P was operated by 420 Air Refueling Squadron based at RAF Sculthorpe Norfolk during the mid - 1950s .