Gulfstream II

In March 1983, Gulfstream, in collaboration with Grumman, initiated the development of the Gulfstream IV, a derivative of the Gulfstream III featuring re-engined design and a stretched fuselage. The first GIV accomplished its maiden flight on September 19, 1985. Following FAA type certification on April 22, 1987, the aircraft entered service in 1987 with serial number 1000. The G-IV was later upgraded to the special purpose GIV-SP version starting at serial number 1214 in 1993, and eventually redesignated as G400 starting at serial number 1500. A shorter-range variant, derived from the GIV, was introduced in 2002 with the G300 designation. In 2001, Gulfstream commenced work on an enhanced iteration of the GIV-SP, initially named GIV-X, later rebranded as G450, which is lengthened by 1 ft (0.305 m) compared to the G400 and shares the forward fuselage and larger cockpit design of the G550. Following its first flight on April 30, 2003, production of the G450 began in October 2004, succeeding the G400. A shorter-range version of the G450, the G350, was developed and certified in 2004. The last of the G450’s was delivered on 19 January 2018 after 365 deliveries over 12 years, ending its production run.

Design

Compared to the Gulfstream III, the Gulfstream IV incorporated a redesigned wing structure for weight reduction and aerodynamic improvements to reduce cruise drag and increase range. These wing contour modifications focused on the forward 65% of the wing chord. Outboard wing modifications aimed to reduce the peak subcritical pressure coefficient, moving it aft to decrease shock strength and increase shock sweep. Power was provided by Rolls-Royce Tay fanjet engines. Aerodynamic improvements resulting from the wing design also contributed to an increased range of over 300 nautical miles. The Gulfstream IV distinguished itself as the first business jet to feature a complete glass cockpit. The G450 variant offered the PlaneView cockpit with four 14-inch (355 mm) liquid crystal displays and a Head-Up Display (HUD).

Operational History

The Gulfstream IV and its derivatives have seen diverse operational use. The National Oceanic and Atmospheric Administration (NOAA) operates a specially-modified GIV-SP for hurricane research, flying scientists and crew at high altitudes to deploy dropsondes and gather meteorological data. Several military variants, designated C-20F/G/H/J, are utilized by the U.S. military for command/executive transport and cargo operations, with the C-20G notably serving the Marine Corps at Kaneohe Bay. The C-20G variant can be configured for cargo operations, 26-passenger operations, or combinations of the two. With passenger seats removed, the C-20G can be configured to hold three pallets with no passengers, two pallets and eight passengers, or one pallet and fourteen passengers. The aircraft can accommodate up to twenty-six passengers and a crew of four with full seating. A hydraulically operated cargo door is installed on the starboard side, and a ball roller cargo floor accommodates palletized cargo. Multiple air forces and government operators across the globe employ GIV variants for VIP transport, electronic intelligence, and other specialized roles.

Variants

Main Variants:

• C-20F: This is a GIV model operated by the U.S. Army in a command/executive transport role.

• C-20G: Configurable for cargo, passengers, or a combination, this variant features a cargo door and ball roller cargo floor.

• C-20H: This is a GIV-SP model operated by the U.S. Air Force in a command/executive transport role.

• C-20J: This is a GIV-SP model operated by the U.S. Army in a command/executive transport role.

• G450: An improved version of the GIV-SP, it features a longer fuselage, enhanced performance, and the PlaneView cockpit.