It's a P2V Neptune, seen at 1:09:38. RAF Coastal Command received 52 P2V-5's designated Neptune MR.1's.
https://www.youtube.com/watch?v=5My2KyaZt60
RAF Neptune fates,
http://www.rafcommands.com/forum/sho...-Neptune-fates
https://en.wikipedia.org/wiki/The_Si...emy_(1958_film)
Inaccuracy - 3.In the film Crabb dives on the wreck of a recently crashed B-24 Liberator that had gone into the sea just after taking off from Gibraltar Airport. This scene was based on the accident in 1943 in which Polish general Władysław Sikorski was killed. In the film the submerged wreck of a Lockheed P2V is used as a stand-in for the Liberator.