The CH-47D was the result of June 1976 contract for a modernized Chinook.The improvements included a redesigned cockpit to reduce pilot workload, an advanced flight control system, and improved avionics. The Chinook has two tandem three-bladed counter-rotating fiberglass rotors. The CH-47D is powered by two Allied Signal Engines T55-L-712 3750 shp turboshaft engines and has a maximun speed of 163 mph. The CH-47D made its first flight in May 1979. The CH-47D carrys twice the load of a CH-47A and has improved performance. The CH-47D can operate at night and in nearly all weather conditions. The CH-47D is equipped with an air-to-air refueling probe.
The Chinook can accommodate a wide variety of internal payloads, including vehicles, artillery pieces, 33 to 44 troops, or 24 litters plus two medical attendants. The "D" model can carry up to 26,000 pounds externally. The CH-47D has three cargo hooks: a center (main) hook and two additional hooks fore and aft of the main hook Engine: 2 Lycoming T-55-L-714turboshaft, 3,750 shp each Rotor Diameter: 60 ft Fuselage Length: 51 ft Overall Length: 99 ft Height: 18 ft 7 in Empty Weight: 22,452 lb Max Takeoff Weight: 50,000 lb Max Speed: 185 mph Ceiling: 17,000 ft Range: 1,250 miles Crew: 2