Based on the stretched fuselage
Bell 205, the Bell 212 was originally developed for the
Canadian Forces as the
CUH-1N and later redesignated as the
CH-135. The Canadian Forces took delivery of 50 starting in May 1971. At the same time the
United States military services ordered 294 Bell 212s under the designation UH-1N. Bell 212 used as
air ambulance by the
Ministry of the Interior By 1971, the Bell 212 had been developed for commercial applications. Among the earliest uses of the type in civil aviation was by
Helicopter Service AS of Norway to be used in support of
offshore drilling; it proved popular across the offshore sector in particular as it had been certified for operating under marginal weather conditions. Today, the 212 can be found used in logging operations, maritime rescue and resupply in the Arctic on the
Distant Early Warning Line or
North Warning System. The 212 is powered by a
Pratt & Whitney Canada PT6T-3 Twin-Pac made up of two coupled
PT6 power turbines driving a common gearbox. They are capable of producing up to 1,800 shp (1,342 kW). Should one power section fail the remaining section can deliver 900 shp (671 kW) for 30 minutes, or 765 shp (571 kW) continuously, enabling the 212 to maintain cruise performance at maximum weight. Early 212s configured with an Instrument Flight Rules (IFR) package were required to have a large and very obvious fin attached to the roof of the aircraft, above and slightly behind the cockpit. This fin was initially determined necessary to alter the turning performance of the aircraft during complex instrument flight maneuvers, but is no longer required due to revised stipulations of the type certificate. Many aircraft still fly with the modification. In 1979, with the purchase of eight by the Civil Air Authority, the 212 became the first U.S. helicopter sold in the
People's Republic of China. The
ICAO designator for this aircraft as used in a
flight plan is "B212". Bell developed the Model 212 further with the
Bell 412; the major difference being the composite four-blade main rotor. The last Bell 212 was delivered in 1998. ==Variants==