Sextant, Aircraft Periscopic, RAF Mk II, Ref No 6B/2838 KC-135 which is usually simple to

which is usually simple to do

or very similar to

It has a screw-type heeling compensator

2 inch by 7-inch wide negatives in 120-type film

It is number eight in the Fixed Gunnery and Combat Tactics series

Sextant, Aircraft Periscopic, RAF Mk II, Ref No 6B/2838 KC-135 which is usually simple toHere is an original aircraft Periscopic Sextant Mk II as used in aircraft of the British Royal Air Force, in its original carrying case. The periscopic sextant was used in aircraft with a pressurized cabin, whereas the 'periscope' was inserted through a shutter mounted in the ceiling of the aircraft. This provided an unobstructed view of the sky for celestial navigation without compromising the pressurization of the crew cabin. The serial number of