Gyro rate unit (original) (raw)

Gyro rate unit refers to a fire-control computer developed by the Royal Navy of the United Kingdom in 1937, and which was used extensively on British warships in World War II. In the 1930s the Royal Navy began to investigate the possibility of combining gyroscopes with optical sights to directly and accurately measure target aircraft speed and direction and began development of the GRU in 1937. A gyroscope was attached, via mechanical linkage, to an optical monocular sight to form the gyro rate unit or GRU.