EA-37B Compass Call

The EA-37B Compass Call is an electronic warfare aircraft operated by the United States Air Force, based on the Gulfstream G550 business jet airframe and modified with mission equipment supplied by L3Harris and BAE Systems. It replaces the EC-130H Compass Call in the Counter-C5ISRT role, jamming enemy command and control communications, radars and navigation systems, and supporting Suppression of Enemy Air Defenses missions. The first operational aircraft was delivered on 23 August 2024.

Development

The US Air Force awarded L3 Technologies a contract on 7 September 2017 to replace the EC-130H with a G550-based platform, re-hosting up to 70 percent of the existing mission equipment. The first airframe was purchased in FY17 under the interim designation EC-X, and Congress accelerated the programme in FY19. The Secretary of the Air Force approved Air Combat Command's basing request on 23 October 2018, with the basing decision memorandum signed on 15 November 2018, assigning the type to the 55th Electronic Combat Group at Davis-Monthan AFB, Arizona. First flight took place on 25 August 2021, and the first aircraft was delivered for testing on 12 September 2023. The designation changed from EC-37B to EA-37B on 14 November 2023. Ten aircraft were originally planned; Congress added two more in FY26, restoring the fleet to twelve. Five had been delivered as of May 2025, with five more planned through 2028. Initial operational capability is scheduled for 2026 following a ten-month slip attributed to component obsolescence and changing requirements.

Design

The airframe is a Gulfstream G550 fitted with large conformal antenna arrays on both sides of the fuselage, derived from those of the G550 CAEW. Power comes from two Rolls-Royce BR700-710 C4-11 turbofans of 15,385 lbf thrust each, giving a maximum speed of Mach 0.82, a range of 3,830 nmi and a service ceiling of 45,000 ft. Maximum takeoff weight is 98,000 lb against an empty weight of 48,300 lb, with 41,300 lb of fuel. Mission systems include BAE Systems' Small Adaptive Bank of Electronic Resources (SABER), the Advanced Radar Countermeasure System (ARCS) and the System-Wide Open Reconfigurable Dynamic Architecture (SWORD-A), together with Network Centric Collaborative Targeting, Radio Frequency Receiver and software-defined radio subsystems, a Counter Radar Assembly, AN/ARC-210 RT-2036 radios, KG-250 in-line network encryptors, KY-100 terminals and KIV-77 Mode 4/5 IFF. Crew is up to nine: two pilots plus a mission crew commander, weapon system officer, mission crew supervisor, analysis operators, an acquisition operator and an airborne maintenance technician.

Operational History

The first mission training sortie was flown on 2 May 2025 by the 43rd Electronic Combat Squadron from Offutt AFB, Nebraska, and initial operational testing was completed in July 2025. Test aircraft operate from Edwards AFB, California. Two aircraft departed Davis-Monthan AFB on 30 March 2026 on the type's first operational deployment, staging through Joint Base McGuire-Dix-Lakehurst and RAF Mildenhall on 31 March before departing for the US Central Command area of responsibility on 2 April 2026. US Central Command confirmed on 1 April 2026 that the type was participating in Operation Epic Fury alongside RC-135 Rivet Joint aircraft. The Italian Air Force has ordered two EA-37B mission system packages to convert two G550 airframes.