Two 3040kW (4075shp) takeoff rated Lycoming AL 5512 turboshafts driving two three-blade rotors.
LR, MLR & ER - Max speed 278km/h (150kt), max cruising speed 270km/h (145kt), long range cruising speed 250km/h (135kt). Max initial rate of climb at MTOW 1180ft/min. Range - LR & MLR with max fuel 1150km (620nm), ER with max fuel 1918km (1035nm). UT - Max speed 260km/h (140kt), max cruising speed 260km/h (140kt), long range cruising speed 250km/h (135kt). Max initial rate of climb at MTOW 1500ft/min. Range with max internal load 425km (230nm).
LR - Empty 11,748kg (25,900lb), max takeoff 22,000kg (48,500lb), or 23,133kg (51,000lb) with an external load. ER - Empty 12,020kg (26,500lb), max takeoff same. MLR - Empty 11,113kg (24,500lb), max takeoff same. UT - Empty 9797kg (21,600lb), max takeoff 19,051kg (42,000lb), or 23,133kg (51,000lb) with an external sling load.
Two pilots on flightdeck. Seating for 44 at four abreast in main cabin. Combi versions seat between eight and 32 with rear cabin loaded with freight, or between 22 and 32 with freight on one side of main cabin. Max internal load of LR and MLR models 9070kg (20,000lb), ER and UT models 8730kg (19250lb). Max external sling load 12,700kg (28,000lb).
Approximately a dozen Commercial Chinooks were built in the early to mid 1980s. Most remain in service.
Heavylift utility and airliner helicopter
The Boeing Helicopters Model 234 Commercial Chinook is, as its name suggests, a commercial variant of the successful CH47 Chinook military airlifter.
The Chinook was developed for the US Army and first flew in September 1961, and since then has been developed into a number of progressively improved variants. The Commercial Chinook was not launched until 1978, following a British Airways Helicopters order for three for North Sea oil rig support missions. The Commercial Chinook's first flight occurred on August 19 1980, certification was granted in June 1981, and service entry was the following month.
Largely identical in configuration to the CH47, the Commercial Chinook retains the former's rear cargo ramp, but has a slightly reprofiled nose, commercial avionics and large passenger windows along both sides of the main cabin.
The initial orders were for the 234 LR Long Range, which compared with the CH47 has roughly twice the fuel load, plus a 44 seat passenger interior based on that used in Boeing jetliners. A number of other versions were offered - the 234 ER Extended Range with additional tankage, the 234 UT Utility, and 234 MLR Multi purpose Long Range which can be used for passenger or freight operations, or a combination of both.