The aircraft used in the film is a B-50, a modified version of the venerable B-29 Superfortress of World War II fame. B-29s were used in the Korean War early on, but by 1952 had been mostly phased out for the somewhat updated B-50 version.
The Flight Engineer (equivalent to a Crew Chief, the top enlisted airman on the crew) in this film is a Technical Sergeant. The post was usually held by a Master Sergeant, but could be held by the top NCO on the crew, at the time usually a Tech Sgt., as Master Sgt. was the top enlisted rank in the Air Force at the time-and would remain so until the creation of "Super NCO" Paygrades E-8 (Senior Master Sergeant) and E-9 (Chief Master Sergeant).