Boeing CH-47 Chinook the CH-47 have been developed since the helicopter entered service. The U.S. Army's first major design leap was the now-common CH-47D, which entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilot workload, improved and redundant electrical systems, an advanced flight control system, and improved avionics. The latest mainstream generation is the CH-47F, which features several major upgrades to reduce maintenance, digitized flight controls, and is powered by two 4,733-horsepower Honeywell engines. A commercial model of the Chinook, the Boeing-Vertol Model 234, is used worldwide for logging, construction, fighting forest
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