RP-3

The RP-3 (from Rocket Projectile 3 inch) was a British rocket projectile used during and after the Second World War. Though primarily an air-to-ground weapon, it saw limited use in other roles. Its 60 lb (27 kg ) warhead gave rise to the alternative name of the "60 lb rocket"; the 25 lb (11.3 kg) solid-shot armour-piercing variant was referred to as the "25 lb rocket". They were generally used by British fighter-bomber aircraft against targets such as tanks, trains, motor transport and buildings, and by Coastal Command and Royal Navy aircraft against U-boats and shipping. The "3 inch" designation referred to the diameter of the rocket motor tube.

History

The first use of rockets fired from aircraft was during World War I. The "Unrotated Projectiles" were Le Prieur rockets which were mounted on the interplane struts of Nieuport fighters. These were used to attack observation balloons and were reasonably successful. Sopwith Baby and Pup and Home Defence B.E.2 fighters also carried rockets. With the end of the war, the Royal Air Force, intent on retrenching, forgot about the potential uses for rockets fired from aircraft. The British Army, however, did see a use for rockets against low-flying aircraft; from late 1940 parts of Britain were defended by increasing numbers of "Z-Batteries" 2-inch (51 mm) rockets supplementing the conventional anti-aircraft guns.