In late 2015, the RAAF ordered two Gulfstream G550 aircraft to be delivered by 30 November 2017. The aircraft will be used for SIGINT and ELINTintelligence gathering.[3] It is reported that the aircraft will possibly form the replacement for the electronic intelligence-gathering role performed by two of the RAAF's AP-3 Orions.[3][4] In June 2017, the sale was approved, and the United States confirmed that Australia was interested in purchasing up to five airframes, to be delivered in two tranches from the early 2020s.[5][6] In March 2019, the Minister for Defence and Minister for Defence Industry in a joint statement announced the procurement of four modified Gulfstream G550 aircraft for use in electronic warfare missions. The aircraft, to be designated MC-55A Peregrine in Australian service, are to be modified in the U.S. and delivered to RAAF Base Edinburgh in a deal worth US$1.7 billion.[7]
Bahrain
The Kingdom of Bahrain is known to use a Gulfstream G550 as a state aircraft and for transporting its royal family.[citation needed]
Germany
German Aerospace Center (DLR) – one G550 special mission aircraft. The aircraft is dubbed HALO (High Altitude and Long Range Research Aircraft). The aircraft's primary objective is to explore the atmosphere and its carbon cycle. Its unique configuration allows a flying altitude of more than 15 kilometers (49,500 feet), a range of more than 8,000 kilometers, and a load capacity of three tons.[8][9]
Israel
Israeli Air Force – two Eitam CAEW (Conformal Airborne Early Warning) and Three Shavit SEMA (Special Electronic Missions Aircraft) aircraft[10]
Italy
Italian Air Force – two G550 CAEWs as part of a counter-deal to Israel's $1 billion order for 30 Alenia Aermacchi M-346 advanced jet trainers.[11] Both aircraft delivered and in service as of January 2018.[12] In December 2020 Italy decided to buy additional 8 G550; the first two will be equipped for AISREW (Airborne Intelligence, Surveillance, Reconnaissance, and Electronic Warfare) mission with a L3Harris suite and the remaining six would be delivered as "green" aircraft to be fitted with mission systems at a later date.[13]
Various companies are known to own and operate G550s, among the most well-covered being those acquired by Elon Musk in 2020 and 2021. Musk's two most recently purchased G550s were formerly owned by Wells Fargo and Contrail Aviation LLC.[28]
The following individuals have been reported to own G550s at some point: