Neptunes for the Royal Air Force were allocated US Air Force rather than US Navy serials. When the aircraft were returned in 1957-58, many received a wrong serial. "51-15956" was really 51-15931, British serial WX505. To Brazil as FAB 7002. The real 51-15956 (c/n 5161), WX543, later to FAB 7000, returned as 51-15931. This is evidently not a 1951 delivery photo of 51-15956 as the aircraft had no MAD boom back then.
This photo was added on 27 January 2024, and has since been viewed 101 times.