1987. It was registered with the Weeks Museum as N29KW. Allied nations United Kingdom During the early 1950s, the Royal Air Force urgently needed interim aircraft for its bomber units, as a "stop gap" replacement for the Avro Lincoln, until British-designed and manufactured jets like the English Electric Canberra and, in the longer term, the so-called "V bombers", became operational. From the RAF's point of view the B-29, was a heavy bomber comparable to the Lincoln, albeit with distinct performance and capacity advantages and, as a type that had already been proven operationally, did not detract from the development of the British jets. A formal agreement with the USA was signed on January 27, 1950 and the USAF loaned the RAF seventy B-29 bombers which received the serials WF434-WF448, WF490-WF-514 and WF545-WF574. Later another 18 were delivered under serials WW342-WW356 and WZ966-WZ968. The aircraft received the service name Boeing Washington B.1 (B.1 from "Bomber Mark 1") with RAF Bomber Command from 1950 as a longer-range nuclear-capable bomber, pending the introduction of the English Electric Canberra in quantity. Most of the airframes were taken out of USAF storage and were virtually new, having been delivered at the end of the Pacific War, although a small number came from operational units. The first 4 aircraft were delivered to the Washington Conversion Unit at RAF Marham on March 22, 1950. All B-29s for the RAF were ferried by the crews of the 307th Bombardment Wing USAF. The first unit converted to Washingtons was No. 115 Squadron RAF which flown from USA in June 1950. Two RAF Washingtons took part in the Laurence Minot SAC bombing competition in 1951 alongside USAF B-29s. Squadrons based at RAF Coningsby were converted to English Electric Canberra bombers in 1953. Squadrons from RAF Marham were converted a year later. Most Washingtons were returned to the United States, being flown by RAF crews to Dover AFB; then subsequently to the aircraft storage facility at Davis-Monthan AFB. A small number of Washingtons remained in the United Kingdom, being used by 192 Sq. for Electronic Intelligence operations until 1958; later being used as ground target airframes for RAF combat aircraft. Royal Air Force RAF Marham No. 35 Squadron RAF No. 90 Squadron RAF No. 115 Squadron RAF No. 207 Squadron RAF RAF Coningsby No. 15 Squadron RAF No. 44 Squadron RAF No. 57 Squadron RAF (moved from RAF Waddington in April