American production, black & white (I believe), so guessing mid-50s to early 60s. Caught only last ~15-20 minutes of movie (about 45-50 years ago) on TV, so can’t help with other scene(s). Likely a “B” movie, but unsure. Actor unknown. Climactic scene(s) included: an activated or damaged atom bomb (capsule shaped) sitting on or near runway at base or airport, then being chained to either a bomber or helicopter by hero pilot who sacrifices self to radiation exposure and flies bomb away from city (over ocean?). Bomb explodes, killing hero pilot. Disaster averted.
MisterDan Unselected an answer Feb 19, 2021
Excellent – thank you very much, Gorgo! I’ll see if I can find a copy and watch it “again” (after 45+ years, it will seem as if I’m watching it for the first time, I’m sure).