An extract from
Flying Guns – World War 2: Development of Aircraft Guns, Ammunition and Installations 1933-45:
"The Germans were also early experimenters with gyro sights, but were discouraged by technical problems and Luftwaffe indifference. Not until late 1944 did the Askania EZ 42/1-A1 (Einheitszielvorrichtung = standard sighting device), go into production. However, it seems that technical problems had still not been resolved and few saw service, principally in Me 262s, in which it was reported that they were used only as conventional reflector sights."
The US sights were copies of the British GGS (Gyro GunSight). The RAF and USAAF/USN were the only air forces to have an effective gyro sight in WW2.
Tony Williams: Military gun and ammunition
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