The 3.5-inch Forward Firing Aircraft Rocket, or 3.5-Inch FFAR, was an American

rocket A rocket (from , and so named for its shape) is a vehicle that uses jet propulsion to accelerate without using any surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely ...

developed during

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

to allow aircraft to attack enemy

submarines A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or info ...

at range. The rocket proved an operational success, and spawned several improved versions for use against surface and land targets.

Design and development

Following trials by the

Royal Air Force The Royal Air Force (RAF) is the Air force, air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the World War I, First World War on 1 April 1918, on the merger of t ...

of rocket-propelled, air-launched weapons for

anti-submarine warfare Anti-submarine warfare (ASW, or in the older form A/S) is a branch of underwater warfare that uses surface warships, aircraft, submarines, or other platforms, to find, track, and deter, damage, or destroy enemy submarines. Such operations ar ...

during 1942 (which resulted in the adoption of the

RP-3 The RP-3 (from Rocket Projectile 3 inch) was a British air-to-ground rocket (weapon), rocket projectile introduced during the Second World War. The "3 inch" designation referred to the nominal diameter of the rocket motor tube. The use of a warhe ...

RAF Coastal Command RAF Coastal Command was a formation within the Royal Air Force (RAF). It was founded in 1936, when the RAF was restructured into Fighter, Bomber and Coastal commands and played an important role during the Second World War. Maritime Aviation ...

), the

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

launched a high-priority project during the summer of 1943 for the development of an anti-submarine rocket of its own.Parsch 2004 The resulting rocket was a simple design with four tail fins for stabilization at the rear, powered by a rocket motor that had been under development by

Caltech The California Institute of Technology (branded as Caltech) is a private university, private research university in Pasadena, California, United States. The university is responsible for many modern scientific advancements and is among a small g ...

since 1943. The warhead contained no explosive. The rocket's nose was a solid steel mass, weighing , that punctured the

pressure hull A submarine hull has two major components, the ''superstructure'' and the ''pressure hull''. The external portion of a submarine’s hull—that part that does not resist sea pressure and is free-flooding—is known as the “superstructure” i ...

of a target submarine through the kinetic energy and momentum from its high velocity and mass.Campbell 1985, p.170. The nose of the 3.5" FFAR was given a relatively blunt conical shape that had been shown experimentally to give a maximum pitch-up as the rocket entered the water. This caused the rocket to shoot forward at a shallow depth deadly to submarines that were surfaced or traveling at snorkel or

periscope depth A periscope is an instrument for observation over, around or through an object, obstacle or condition that prevents direct line-of-sight observation from an observer's current position. In its simplest form, it consists of an outer case with ...

. The rockets were launched in a shallow dive, since entry into the water at too steep an angle would defeat their ability to shoot forward at the required shallow depth. The rocket remained lethal even after passing through up to of water, giving the pilot a target several times the actual size of the submarine. The sweet spot for targeting was considered to be in front of the near side of the submarine. Typical firing range was about .

Operational history

Following expedited development, the weapon, officially designated the "3.5-inch forward firing aircraft rocket", entered operational service with the U.S. Navy late in 1943; production of 10,000 rockets per month had been ordered that August. The FFAR's first "kill" of an enemy submarine took place 11 January 1944. The rocket was originally carried by the

Grumman TBF Avenger The Grumman TBF Avenger (designated TBM for aircraft manufactured by General Motors) is an American World War II-era torpedo bomber developed initially for the United States Navy and Marine Corps, and eventually used by several air and naval a ...

torpedo bomber A torpedo bomber is a military aircraft designed primarily to attack ships with aerial torpedoes. Torpedo bombers came into existence just before the World War I, First World War almost as soon as aircraft were built that were capable of carryin ...

s. Excessive drag caused by the original channel-slide launchers was largely eliminated with the introduction of zero-length launchers in May 1945. Zero-length launchers quickly became standard on most fighters and many light bombers for firing a variety of rockets with 3.25" or 5" diameter rocket motors. Although the rocket's accuracy was more than sufficient to allow usage against surface targets, the narrow body diameter restricted the size of any explosive warhead that could be fitted. Therefore, for use against ships and land targets, the rocket was given a warhead consisting of a re-fused 5" (127 mm) Mark 35 artillery shell, producing the 5-inch forward firing aircraft rocket, usually shortened to 5" AR.Parsch 2006

References

;Citations ;Bibliography * * * * *

External links

{{USA WW2 rockets Anti-submarine missiles of the United States World War II weapons of the United States Weapons and ammunition introduced in 1943

Design and development

Operational history

See also

References

External links