First flown on 2 November 1977,[1] the cruise speed of the aircraft was increased to 230 mph (200 kn; 370 km/h).

The engine mounted on the nose could be shut off, decreasing the speed to 180 mph (160 kn; 290 km/h) and increasing the range of the aircraft.

It was uniquely suited for flying long distances and landing on rough, unprepared snow runways.

In this role it was instrumental in opening up the interior of Antarctica to private expeditions and tourism.

[2] Data from The Illustrated Encyclopedia of Propeller Airliners[3]General characteristics Performance Related development Aircraft of comparable role, configuration, and era