Gulfstream G100

The Gulfstream G100 is a twin-engine mid-size business jet built by Israel Aerospace Industries (IAI) and marketed for most of its life as the IAI 1125 Astra. It was developed from IAI's Model 1124 Westwind and first flew in 1984, entering service in 1986. After Gulfstream acquired Galaxy Aerospace, holder of the Astra type certificate, in May 2001, the final Astra SPX version was renamed Gulfstream G100 in September 2002. The type has seen limited military use, most notably as the US Air Force and US Navy C-38A Courier, and its wing formed the basis of the larger IAI Galaxy, later the Gulfstream G200.

Development

Work on an improved Westwind began in the late 1970s. Rather than a modest update, the project gave the aircraft a new swept wing using the IAI Sigma-2 airfoil, and the result was designated the IAI 1125 Astra. The prototype made its first flight on 19 March 1984, the first production aircraft flew on 20 March 1985, and FAA certification followed on 29 August 1985. Customer deliveries began in 1986.

The Astra SP, announced in 1989, introduced modified aerodynamics that added about 98 km (53 nmi) of range, along with improved avionics and a revised interior. The Astra SPX first flew in August 1994 with more powerful Honeywell TFE731-40R-200G turbofans, winglets, higher operating weights and greater range. It is this version that became the G100 under Gulfstream ownership.

In September 2002 Gulfstream announced the G150, a derivative of the G100 with a cabin 30 cm (12 in) wider, a longer fuselage, a revised nose, updated avionics and a maximum take-off weight of 11,839 kg (26,100 lb). It first flew on 3 May 2005 and received FAA certification late that year; it was also certified for the steep approach into London City Airport. Airframes were built by IAI in Israel and flown to Dallas, Texas, for interior completion. Gulfstream sold the last G150 in September 2016, after a ten-year production run during which the type was overtaken in its own market segment by the larger G280 introduced in 2012; the final delivery took place in mid-2017. Total production of the family reached 265 aircraft: 145 Astra and G100 and 120 G150.

The Astra wing was also mated to an entirely new, wider fuselage to produce the IAI Galaxy, later sold as the Gulfstream G200.

Design

The G100 has two rear-mounted turbofans and a crew of two, and carries six to nine passengers. The original Astra was powered by two Garrett TFE731-3A-200G engines of 16.46 kN (3,700 lbf) each; the SPX and G100 use Honeywell TFE731-40R-200G turbofans rated at 18.9 kN (4,250 lbf) each.

The aircraft is 16.94 m long, spans 16.64 m over the winglets and stands 5.54 m high, with a wing area of 29.41 m². Empty weight is 6,214 kg and maximum take-off weight 11,181 kg (24,650 lb), with 4,910 L of usable fuel. Maximum speed is Mach 0.875 and cruising speed 896 km/h (484 kt). With maximum fuel and four passengers, range is 5,462 km (2,949 nmi). Service ceiling is about 13,700 m (45,000 ft) and the rate of climb 19.3 m/s. The cockpit is fitted with Collins Pro Line 4 avionics.

Military service

The United States ordered the type in 1997 for the US Air Force as the C-38A Courier, an Astra SPX fitted with military avionics. The two aircraft replaced the Learjet C-21 with the 201st Airlift Squadron, District of Columbia Air National Guard, at Andrews Air Force Base, Maryland, which operated them until 2015. Both then passed to the US Navy, where they replaced T-2 Buckeyes with Air Test and Evaluation Squadron 20 (VX-20) at Naval Air Station Patuxent River, Maryland. There the C-38A flies as a chase aircraft in the test programmes of the P-8A, E-2D, MQ-4C, E-6B and C-130, serves as an airborne radar target, supports pilot proficiency and transports officials. Two remained in service as of 2023.

The Indian Air Force operates two G100s. In Taiwan, the Aerospace Industrial Development Corporation (AIDC) operates one Astra SPX as a target tug.

The Eritrean Air Force operated a single Astra as the presidential aircraft. In October 2012 two serving Eritrean Air Force officers flew it to Jizan, Saudi Arabia, and requested political asylum; Saudi Arabia refused to return either the aircraft or the crew.

Many used Astras and G100s have found a second career as air ambulances, including with operators in Canada.

Variants

• IAI 1125 Astra: original production version, powered by Garrett TFE731-3A-200G turbofans; deliveries from 1986.
• Astra SP: announced in 1989 with modified aerodynamics adding about 98 km (53 nmi) of range, improved avionics and a revised interior.
• Astra SPX: first flown in August 1994 with Honeywell TFE731-40R-200G engines, winglets, higher weights and greater range.
• Gulfstream G100: the Astra SPX as renamed by Gulfstream in September 2002.
• C-38A Courier: US military version of the Astra SPX with military avionics, two ordered for the US Air Force in 1997 and transferred to the US Navy in 2015.
• Gulfstream G150: enlarged derivative with a wider cabin, longer fuselage, revised nose and updated avionics; 120 built, the last delivered in mid-2017.