Boeing HH-47 CSAR-X

The Boeing HH-47 CSAR-X was a proposed combat search and rescue helicopter, a derivative of the CH-47 Chinook that Boeing offered as a medium to heavy lift alternative to the HH-60 Pave Hawk. The Air Force wanted a helicopter that could fly out 316 miles, loiter for five minutes during an extraction and return, compared with 213 miles for the Pave Hawk. The design added forward-looking infrared pods, terrain avoidance radar, a rescue hoist, in-flight refuelling, an anti-corrosion layer, heavier armour, wire strike cutters and an environmentally controlled treatment area for four litters. Boeing was pronounced the winner and four development aircraft and 141 production aircraft were planned, but Lockheed Martin protested and requested a Government Accountability Office review in 2007, and the Air Force did not choose the HH-47; the HH-60W entered service in 2020 instead.