''Le Prieur'' rockets (French ''Fusées Le Prieur'') were a type of incendiary

air-to-air rocket An air-to-air rocket or air interception rocket is an unguided projectile fired from aircraft to engage other flying targets. They were used briefly in World War I to engage enemy observation balloons and in and after World War II to engage enem ...

used in

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...

against

observation balloon An observation balloon is a type of balloon that is employed as an aerial platform for intelligence gathering and artillery spotting. Use of observation balloons began during the French Revolutionary Wars, reaching their zenith during World War ...

s and

airship An airship or dirigible balloon is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power. Aerostats gain their lift from a lifting gas that is less dense than the surrounding air. In early ...

s. They were invented by the French

lieutenant A lieutenant ( , ; abbreviated Lt., Lt, LT, Lieut and similar) is a commissioned officer rank in the armed forces of many nations. The meaning of lieutenant differs in different militaries (see comparative military ranks), but it is often ...

Yves Le Prieur and were first used in the

Battle of Verdun The Battle of Verdun (french: Bataille de Verdun ; german: Schlacht um Verdun ) was fought from 21 February to 18 December 1916 on the Western Front in France. The battle was the longest of the First World War and took place on the hills north ...

in April 1916. Due to great inaccuracy their range was limited to about .

Development

The Le Prieur rocket was essentially a cardboard tube filled with 200 grams of black powder with a wooden conical head attached (by doped paper or linen tape) and had a triangular knife blade inserted in a slot across its apex forming a spear point. A square-section wooden stick (usually pine) was taped to the fish with about extending back from the base of the rocket and fitted snugly into a launch tube attached to the aircraft inter-plane struts. As top French military officers had expressed concerns about fire hazard for the attacking aircraft, Yves Le Prieur first experimented with his weapon by fitting one on a short section of a Voisin aircraft wing bolted on a Piccard Pictet (

Pic-Pic Pic-Pic was a Swiss automobile manufactured in Geneva from 1906 to 1924. They were produced by the Piccard-Pictet Company (whence its name derives) until 1920, and by Gnome et Rhône from 1920 until the demise of the marque in 1924. History In t ...

) automobile (one of the few period cars with a genuine capability). As the tests went on with full success, the weapon was soon put into active service.

Method of use

The rockets were fired electrically from the

interplane strut In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of strut, which act in ...

s supporting the wings of

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While a ...

s via a cockpit switch. The switch launched all the rockets consecutively. The rockets were generally fired at a range of 100–150 metres with the aircraft at an inclined dive angle of 45 degrees. The steeper the dive the straighter the trajectory and the more accurate the attack. Attacks were made in the direction of the length of the balloon and against the wind, the pilot taking aim via the plane's existing gun-sight. However, the ignition and discharge of each rocket did not occur immediately and a delay varied slightly from one rocket to another. Thus the pilot had to continue to hold the target in his gun-sight and the dive continued until the last rocket discharged. It successfully brought down observation

balloon A balloon is a flexible bag that can be inflated with a gas, such as helium, hydrogen, nitrous oxide, oxygen, and air. For special tasks, balloons can be filled with smoke, liquid water, granular media (e.g. sand, flour or rice), or lig ...

s, but never managed to bring down a

Zeppelin A Zeppelin is a type of rigid airship named after the German inventor Count Ferdinand von Zeppelin () who pioneered rigid airship development at the beginning of the 20th century. Zeppelin's notions were first formulated in 1874Eckener 1938, pp ...

, although it was used to defend the United Kingdom from Zeppelin raids. Amongst users of the rockets were United Kingdom, France, Belgium and Germany. After planes became equipped with

tracer rounds Tracer ammunition (AMO) (Tracers) are bullets or cannon-caliber projectiles that are built with a small pyrotechnic charge in their base. When fired, the pyrotechnic composition is ignited by the burning powder and burns very brightly, making th ...

and incendiary bullets which were highly effective against hydrogen filled aerostats, the rockets were gradually abandoned through 1918. Aircraft that were armed with the rockets included the B.E.2,

B.E.12 The Royal Aircraft Factory B.E.12 was a British single-seat aeroplane of The First World War designed at the Royal Aircraft Factory. It was essentially a single-seat version of the B.E.2. Intended for use as a long-range reconnaissance and bom ...

Sopwith Baby The Sopwith Baby is a British single-seat floatplane that was operated by the Royal Naval Air Service (RNAS) from 1915. Development and design The Baby (also known as the Admiralty 8200 Type) was a development of the two-seat Sopwith Schneider. ...

Sopwith Pup The Sopwith Pup is a British single-seater biplane fighter aircraft built by the Sopwith Aviation Company. It entered service with the Royal Naval Air Service and the Royal Flying Corps in the autumn of 1916. With pleasant flying characte ...

Sopwith Camel The Sopwith Camel is a British First World War single-seat biplane fighter aircraft that was introduced on the Western Front in 1917. It was developed by the Sopwith Aviation Company as a successor to the Sopwith Pup and became one of the ...

Nieuport 11 The Nieuport 11 (or Nieuport XI C.1 in contemporary sources), nicknamed the ''Bébé'', was a French World War I single seat sesquiplane fighter aircraft, designed by Gustave Delage. It was the primary aircraft that ended the Fokker Scourge in ...

Nieuport 16 The Nieuport 16 C.1 (or Nieuport XVI C.1 in contemporary sources)The C in the designation indicates that it is a ''chasseur'' or fighter, and the 1 indicates the number of crew members. was a French World War I single-seat sesquiplane fighter air ...

Nieuport 17 The Nieuport 17 C.1 (or Nieuport XVII C.1 in contemporary sources) was a French sesquiplane fighter designed and manufactured by the Nieuport company during World War I. An improvement over the Nieuport 11, it was a little larger than earlier ...

SPAD S.VII The SPAD S.VII was the first of a series of highly successful biplane fighter aircraft produced by ''Société Pour L'Aviation et ses Dérivés'' (SPAD) during the First World War. Like its successors, the S.VII was renowned as a sturdy and rug ...

, SPAD S.XIII and the Farman HF.20/21. They were usually armed with eight rockets but the B.E.12 had ten and the SPAD 7 had six.

References

*{{cite magazine , last=Jarry , first=Maud , title=Les fusées d'Yves Le Prieur en 1916: La bataille des saucisses , magazine=Le Fana de l'Aviation , date=September 2003 , issue=406 , pages=28–35 , language=fr

External links

The Pioneers—Yves Le Prieur
World War I weapons of France Air-to-air rockets

Development

Method of use

See also

References

External links