The actual date of completion for the aircraft will be difficult to determine as the Cutlass program was a prime example of poor program management at the bleeding edge of aeronautical technology. Problems with deliveries of program designated Westinghouse J46 engine to the Vought plant meant that Vought had engineless airframes parked on their factory ramp for an extended period after they began coming off the line in 1951. The first F7U-3 with the J46 did not fly until April 1953. The production line continued until mid-1954.
Bureau number 129565 was the 21st airframe off the production line in the second (and largest) largest batch of F7U-3 orders (BuNo 129545-129676). If I were to hazard a guess, I would say that 129565 came off the line in late 1951/early 1952, sat at Vought for a couple of years and was finally delivered to the Navy in 1954.
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