The Gulfstream I (company designation G-159) is a twin turboprop business aircraft. It first flew on August 14, 1958.

The Gulfstream I is a low-wing cantilever monoplane with a semi-monocoque aluminum alloy fuselage structure. The aircraft is powered by two Rolls-Royce Dart turboprops with four-bladed constant speed propellers. The Gulfstream I has a retractable tricycle landing gear, with twin wheels on the two main units and the nosewheel. The cabin is designed to take up to twenty-four passengers in a high-density arrangement or only eight in an executive layout, although ten to twelve was more usual. The aircraft has a hydraulically operated airstair in the forward cabin for entry and exit.

The United States military version for this plane is the C-4 Academe. The TC-4 is a version with added instruments and navigation. It was used by US Navy for bombardier/navigator training for the A-6 Intruder. A VC-4A variant was flown by the United States Coast Guard as an executive transport until the early 1980s. It was later used as a logistics and long-range command and control aircraft until 2001.

A 37-passenger stretched version, the G-159C, was developed by Gulfstream for regional airline use. Five were delivered from November 1980.  Air North (Plattsburgh NY) (which subsequently changed its name to Brockway Air) was one the few airlines in the U.S. to use this version before its acquisition by Brockway Glass. Another Gulfstream I-C airline operator was Chaparral Airlines which flew passenger services as American Eagle via a codesharing agreement with American Airlines. Royale Airlines also operated the G-I in scheduled passenger service in the U.S. operating as Continental Connection on behalf of Continental Airlines; however, its aircraft were standard length G-159 models and thus were not the stretched version. Several other airlines in the U.S. as well air carriers in Africa, Canada, Europe and the Mideast also operated standard Gulfstream Is in scheduled passenger service, including Peregrine Air Services in the U.K. which operated airline flights for British Airways.

In August 2006, a total of 44 Grumman Gulfstream I aircraft remain in service. The major operator is Phoenix Air in the United States with 13 aircraft. Some 19 other airlines also operate the type.  A G-1 purchased by Walt Disney in 1964 and last flown on Oct. 8, 1992 is on display at Disney's Hollywood Studios near Orlando, Florida. The aircraft logged 8800 flights and 20,000 flight hours with notable passengers Richard Nixon, Ronald Reagan, Jimmy Carter, Julie Andrews, Hugh O'Brian, and Annette Funicello.

Variants

G-159 Gulfstream I

Twin-engined executive, corporate transport aircraft with accommodation for up to 14 passengers, powered by two 2,210-ehp (1648-kW) Rolls-Royce Dart RDa.7/2 Mk 529-8X turboprop engines. 200 built.

G-159C Gulfstream I-C

Stretched regional airline version. Five G-I aircraft were converted into Gulfstream I-Cs, by having the fuselage lengthened by 10 ft 8 in (3.25 m) to provide seating for up to 37 passengers.

VC-4A

VIP transport version for the US Coast Guard. One built.

TC-4B

United States military designation for a cancelled order for ten aircraft for the United States Navy for the navigation training and transport duties.

TC-4C Academe

United States military designation for a bombardier, navigator trainer trainer for the US Navy first flown in 1967. Aircraft were fitted with an Grumman A-6 Intruder nose radome, a simulated A-6 cockpit and four bombadier/navigator consoles for A-6 crew training, nine built.

Specifications

Data from Jane's All The World's Aircraft 1965-66