Argus As 014

Argus As 014. The Argus As 014 was a simple, low-cost pulsejet engine that powered the Fieseler Fi 103, the world's first operational cruise missile known as the V-1 flying bomb. Developed in Nazi Germany during World War II, its distinctive buzzing sound earned it Allied nicknames like "buzz bomb" and "doodlebug." The engine's design, based on the Schmidt tube, represented a significant, if crude, advancement in jet propulsion technology for its era.

Development and design

The As 014 originated from pre-war experiments by inventor Paul Schmidt, whose work on resonant pulsejets was later merged with projects from the German Air Ministry (Reichsluftfahrtministerium). The engine's development was overseen by Robert Lusser of Fieseler and Fritz Gosslau of Argus Motoren, with the latter firm responsible for production. The design was exceptionally simple, consisting of a long sheet metal tube with spring-loaded shutter valves at the front, a fuel injection system, and a spark plug for ignition. This valved pulsejet operated on the Hiller principle, where combustion pulses created thrust without the need for a moving compressor or turbine, making it cheap and quick to manufacture. Key testing took place at the Peenemünde Army Research Center and the Luftwaffe's Erprobungsstelle test facilities.

Operational history

The As 014 entered operational service in June 1944, powering V-1 flying bombs launched from catapult ramps in Nazi-occupied Europe against targets in southern England, particularly London. The engine's unreliability and short operational life—typically around one hour—were offset by the weapon's psychological impact and the difficulty of interception for Allied fighters and anti-aircraft guns. RAF pilots, including those of the Tempest V, developed tactics to tip the missiles over by sliding a wing underneath them. Despite thousands being fired, many failed due to engine malfunctions, and the campaign was largely suppressed by the Allied advance on launch sites. The technology later influenced early postwar jet engine and unmanned aerial vehicle designs in several countries.

Variants

The primary variant was the standard production As 014 used on the Fi 103. An experimental, longer-burn version was tested to extend range. Proposals existed for a "Mistel"-style composite aircraft where a piloted Focke-Wulf Fw 190 would guide a V-1, but this was not operational. The basic design was also studied for potential use on He 111-launched bombs and small, disposable attack aircraft. After the war, captured examples inspired developments like the American Republic-Ford JB-2 and similar projects in the Soviet Union and France.

Specifications (As 014)

* **Type:** Valved pulsejet * **Length:** 3.48 m (11 ft 5 in) * **Diameter:** 0.58 m (1 ft 11 in) at widest point * **Dry weight:** 150 kg (331 lb) * **Components:** * **Valve system:** Bank of 38 spring-steel shutter valves * **Fuel system:** Direct fuel injection into combustion chamber * **Ignition system:** Single spark plug, with a acetylene gas starter system * **Performance:** * **Thrust:** 2.9 kN (660 lbf) at 670 km/h (416 mph) at sea level * **Specific fuel consumption:** Extremely high, approximately 4.0 kg/kN/hr * **Operating speed range:** 640 km/h (400 mph) to 800 km/h (500 mph) for efficient resonance * **Fuel:** Low-grade gasoline * **Operational life:** Approximately 1 hour (30 minutes typical flight time)

Applications

The sole major production application was the Fieseler Fi 103 (V-1 flying bomb). Captured engines and technology were used in the American copy, the Republic-Ford JB-2 Loon. The Soviet Union developed the 10Kh and later Lavochkin La-17 target drones using the design. In France, the SNECMA company developed the SNECMA Écrevisse research pulsejet from As 014 principles. The engine's basic concept also informed early research into ramjet technology and target drone propulsion during the Cold War.

Category:Pulsejet engines Category:World War II German aircraft engines Category:Argus aircraft engines