Compass Call Appears to Take On New Mission

Air Force SSgt. William Urquhart, 755th Aircraft Maintenance Squadron aerospace propulsion, inspects an EC-130H Compass Call engine during Aviation Rotation 19-2 at Krzesiny AB, Poland, on June 13, 2019. Air Force photo by SSgt. Jonathan Snyder.

The Air Force’s EC-130H Compass Call electronic-attack plane has taken on a new role at the intersection of cyber and electronic warfare, according to Capitol Hill researchers.

“Compass Call is normally used to jam enemy radars and communications,” an Aug. 13 Congressional Research Service report said. “However, in recent years, it has been used to transmit computer code to wireless devices using radio frequencies.”

An Air Combat Command spokeswoman declined to comment on that new mission because it is classified. The information comes as the Air Force is merging its intelligence, surveillance, reconnaissance, cyber, and EW forces into a new organization.

It’s unclear whether the Compass Call is passing code between friendly forces or whether it’s meant to disrupt enemy operations. CRS declined to elaborate on its report.

“The most recognizable convergence of electronic warfare and cyberspace operations is when forces transmit computer code to inject it into an adversary’s network,” CRS noted. “In these types of operations, radios can transmit data packets on Wi-Fi networks, even if these networks are closed (i.e., not connected to the internet).”

In 2017, The War Zone reported on a US Central Command document that acknowledged the potential crossover between EW and cyber operations.

“Cyberspace operations may be used to force an adversary from wired to wireless networks that are vulnerable,” the document states. “EW may be used to set favorable conditions for cyberspace operations by stimulating networked sensors, denying wireless networks, or other related actions. In the defensive environment, EW systems may detect and defeat attacks across wireless access points.”

Compass Call entered service in the 1980s, but the Air Force’s secretive Big Safari group routinely updates it with new EW technology. The service is in the process of moving the EC-130H’s equipment into a new fleet of 10 Gulfstream G550s, dubbed the EC-37B. Air Force operators will receive the first EC-37B in 2023, Inside Defense reported last year.