RAE Larynx

The Royal Aircraft Establishment Larynx, whose name stood for "Long Range Gun with Lynx engine," was an early British unmanned aircraft designed to attack ships. Work began in September 1925, and it is regarded as an early cruise missile, steered by an autopilot.

Background

The idea of using an unmanned, explosive-filled aircraft guided by radio had first emerged during the First World War. The Royal Aircraft Factory had previously experimented with monoplane aircraft launched from a track and controlled by an autopilot, a concept developed by Professor Archibald Low. Another early attempt, the Ruston Proctor AT (Aerial Target, a deliberately misleading name), was a radio-controlled biplane designed by Henry Folland to target German Zeppelins, but it performed poorly in demonstrations and was abandoned.

In May 1919, the Admiralty requested a remotely controlled target aircraft for anti-aircraft practice. The Royal Aircraft Establishment began testing a small monoplane similar to the earlier Royal Aircraft Factory design. Trials of pilotless aircraft launched from ships and controlled by wireless from the ship or a nearby aircraft started in 1922. By 1925, research had progressed enough for the Admiralty and Air Ministry to consider using such aircraft for attacks on both air and ground targets.

An unmanned bomber offered several advantages: no need for a pilot, defensive measures, or an undercarriage; it could be faster, fly farther, and carry more bombs in any weather, either dropping them or crashing into the target. With no need to manage low-speed control, maximum speed could be much higher. Such a weapon would be useful against heavily defended targets or as a decoy to protect manned bombers. The possibility that other nations were developing similar technology also pushed Britain to work on countermeasures.

Design

In 1925, the RAE was ordered to build a prototype anti-ship missile capable of flying at 190 mph with 100 lb of explosives—soon increased to 200 lb—for a range of 200 to 300 miles, a bomb load similar to that of the new Fairey Fox. The resulting aircraft, the Larynx, was a small monoplane powered by a 200 hp Armstrong Siddeley Lynx IV engine, giving it a top speed of 200 mph, faster than contemporary fighters. It used the autopilot developed by Professor Archibald Low during the First World War.