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 N
Pom-pom directors, Mk IV on HMS King George V. The large rectangular box centered above the director contains the Gyro Rate Unit. This image was taken early in King George V's career as the directors do not yet have Type 282 radar.