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The CRV7, short for "Canadian Rocket Vehicle 7", is a 2.75 inch (70 mm) folding-fin ground attack rocket produced by Bristol Aerospace in Winnipeg, Manitoba. It was introduced in the early 1970s as an upgraded version of the standard U.S. 2.75 inch air-to-ground rockets. It was the most powerful weapon of its class, the first with enough energy to penetrate standard Warsaw Pact aircraft hangars. The CRV7 remains one of the most powerful air-to-ground attack rockets to this day, and has slowly become the de facto standard for Western-aligned forces outside the United States. ==Development== The CRV7 was an offshoot of late 1950s research at CARDE into high-performance solid fuel rockets, performed as a part of a general program studying anti-ballistic missiles. With Aerojet's assistance, CARDE and Bristol developed the "Propulsion Test Vehicle" to test new fuel and engine designs. This program led to the development of the Black Brant sounding rocket, which first flew in 1965 and has had a long and successful career since then.〔("Black Brant" )〕 In the early 1970s, CARDE and Bristol decided to use the same propellant and engine design for a new 2.75 inch rocket to equip the CF-104 Starfighter.〔("Then and Now: The CRV7" ), Defence Research and Development Canada〕 The resulting RLU-5001/B (C-14) engine was first delivered by Bristol in production form in 1973. It had a total impulse of 2,320 lbf·s (10.3 kN·s) and a burn time of 2.2 seconds. The empty weight of the rocket is 6.6 kg and it is normally equipped with a 10 lb (4.5 kg) high-explosive warhead taken from U.S. rockets. Compared to the U.S. Mk 40 ''Mighty Mouse'' rockets the CRV7 replaced, the higher energy fuel and newer fuselage design led to a longer and much flatter trajectory, with twice the energy on impact. Its maximum effective range is over 4,000 m, allowing launch from beyond the envelope of most short-range anti-aircraft weapons. In comparison, the Mighty Mouse or Hydra 70 requires launches from much shorter ranges, potentially placing the launch aircraft within the range of ground-based weapons arranged around the target.〔''Fixed''〕 Unguided rockets are normally spin stabilized, like a rifle bullet. The spin is imparted by small fins at the rear of the rocket body that flip out into the airstream once the rocket leaves its launch tube. The fins take a short time to open, and more time to start the rocket spinning. During this period the rockets can drift significantly from their original aim point. The CRV7 solved this problem by adding small vanes projecting into the rocket exhaust to start the rocket spinning even before it left the launch tube, greatly increasing accuracy. A salvo of CRV7's will impact the target area in one-third the footprint of older designs.〔 The weapon was originally quoted to have a dispersion of 4 milliradians, but testing with the CF-18 Hornet demonstrated it was even lower, at 3 milliradians.〔("New roles for Canadian rocket" ), ''FLIGHT International'', 11 February 1984, pg. 381〕 This is considerably better than the autocannon that arm most aircraft; the widely used M61 Vulcan is rated at 8 milliradians, while the much larger and considerably heavier GAU-8 is rated at 5 milliradians.〔("GAU-8 Avenger" ), GlobalSecurity.com〕 The CRV7 had just been introduced into Canadian Air Force service when it was entered as a part of a general competition in France. One part of the competition required the contestants to hit a tower with unarmed rockets. The Canadian pilot hit it on his first try, but aimed as if firing the much lower-powered Mk 40 and was therefore close enough that the rocket motor was still firing. The remaining unburned propellant shattered allowing more surface area of the rocket motor to burn, in turn increasing the pressure and rate of combustion to a speed that was no longer considered burning but was now a deflagration and destroyed the tower, and the pilot was disqualified because the judges refused to believe it was unarmed. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「CRV7」の詳細全文を読む スポンサード リンク
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