Grumman G-159 Gulfstream I
As early as 1947 the Grumman Company was working on designs for a twin-engine executive transport aircraft. The concept went through several stages including conversions of existing Grumman designs and all new jet powered concepts. By 1956 they had settled on a turboprop design as the best compromise between speed and affordability. Interest in the aircraft was extremely high and a series of preorders and deposits convinced Grumman to go ahead. The aircraft that emerged on August 14, 1958 could carry up to 24 passengers over 2,000 miles at speeds in excess of 300 miles an hour. A total of 200 Gulfstream I aircraft were built between 1958 and 1969 with the vast majority going into service as corporate transports. A very few were used as airliners, but they quickly proved to be uneconomical in that role. The U.S. Navy purchased nine aircraft for training A-6 Intruder navigators while the Coast Guard purchased one aircraft as a transport. In 1963, NASA purchased five Gulfstreams for both experimental and transport use.