Helicopter deck the submarine, but brushes the officer charged with trying to hook him who receives a minor injury. Coaxial rotor helicopters in flight are highly resistant to side-winds, which makes them suitable for shipboard use, even without a rope-pulley landing system. Marine and offshore helicopter decks on board offshore oil platforms and ships are typically regulated by the rules defined within CAP 437, which defines standards for the design, marking, and lighting of marine/offshore helicopter decks, and is produced by the Civil Aviation Authority. The largest marine heli decks will accommodate the Boeing CH-47 Chinook, which requires a D value of
1978 Iranian Chinook shootdown damaged helicopter and opened fire with GSh-23L 23-mm gun, spending a total of 72 rounds in two passes and hitting the starboard engine of the CH-47C. The Iranian pilot was lucky enough to manage a landing near the Soviet border post at Gjaurs. All four crew members survived, but were subsequently captured by Soviet border guards. The remaining two Chinooks escaped, crossing back into Iranian airspace. Despite a severe loss of life for the IIAF, the incident was played down by both sides, and the Soviets subsequently permitted the damaged Chinook to be repaired by Iranians and flown back to