British RAF "Wimperis" Course Setting Bomb Sight Mk IXA 1940 WWII

This is a prize in my collection of historical military aviation artifacts. The Course Setting Bomb Sight was developed by Harry Wimperis during the years preceding the opening of WWII. The invention solved many issues associated with the aircraft-bomb-dropping problem, including accounting for the aircraft's speed, altitude, wind-drift, weight of the bomb, etc. It is quite a complicated, manual device for the age, appearing as if Jules Verne himself had designed it. It was typically used while the bomb-aimer is exposed to open air from the bottom of the aircraft while in flight (see photo) or from the glass nose of the aircraft. It was used in a number of different RAF bombers during the early part of the war (e.g., Fairey Battle, Bristol Blenheim), eventually giving way to semi-automatic computing bomb sights such as the Sperry S-1, especially for heavy bombers such as Lancasters.

This specimen has a serial number indicating year of manufacture of 1940. It is a near-complete kit, which includes the sight itself, in a wooden case, with a drawer containing the metal scales which affix to the device for different airspeed ranges expected over the target during the bombing run. The only thing that is missing is the mount to attach it to frame of the aircraft hatch.

Now just imagine hanging out of the bottom of an aircraft traveling hundreds of MPH in open frigid air at thousands of feet high, bouncing around in turbulence, while the adversary is shooting at you, trying to operate this contraption in order to accomplish the sole purpose for your aircraft being aloft while risking the lives of your crewmates in doing so. The odds were not in your favor....