Straps, beds, rear springs, and the ATA!
a lever called the 'Pilot's Harness Release Lever' which is situated on the right on the outside front of the arm rest and attached to it (which can be raised so the pilot can get in or out of the seat). This lever looks like it could be hydraulically operated, or some sort of flexible rod, as there seems to be a flexible pipe coming from behind it leading round to the back of the seat.
Once strapped in with the usual Sutton Harness, this additional lever could slacken off the harness, giving the pilot extra movement, e.g, to lean forward to see the magnetic compass. Simply leaning back tightened the harness.
Whitleys, Wellingtons, Lancs and Halifaxes all had lap straps on the "jump" seats. Engineers on Halifaxes seemed to stand behind the pilot as their instrument panel was situated there, and they had to move to change tanks. When we were inverted and dropped 7,000 ft, my engineer "hit the roof."
I think Gunners and Navigators used lap straps.
All the above mentioned heavy bombers had a "bed," or stretcher, in the rear. Carrying an unconscious Bomb-aimer from the bows to the bed, using portable oxygen bottles, was hard work. Other casualties went on the floor (deck.)
[B]rear sear spring retainer keeper. [/B] I remember it well, but I know nothing of the differences between British & American Brownings.
In the sixties and the seventies I regularly met some of the wartime ATA women pilots, and their log books made our eyes water. To qualify for heavy aircraft they attended a Halifax conversion flight. If they passed, they were qualified to fly all four engined aeroplanes, except flying boats.
They had flight engineers (ATA) for the bigger aircraft.