Nash & Thompson was a British engineering firm that developed and produced hydraulically operated gun turrets for aircraft. As part of Parnall Aircraft it was also an important manufacturer of hydraulic-powered radar scanners used on radar systems such as H2S and AI Mark VIII. Nash & Thompson also designed the hydraulically-powered turret traversing systems that were used in British Cruiser tanks from the A9 - the first tank with a powered turret traverse - through to the Cromwell.