The U.S. Air Force has very few weapons that nobody else can match. The EA-37B Compass Call is one of them — a Gulfstream business jet stuffed with classified electronic-attack hardware that can shut down enemy radios, command nets, GPS, and air-defence radars across hundreds of kilometres. It flew its first combat sorties over Iran weeks ago. And now the fleet is about to triple.

Defence contractor L3Harris is poised to receive a $2.9 billion follow-on order for 12 additional EA-37Bs, bringing the planned fleet to 22 aircraft. The Air Force currently operates 10. If approved, the order doubles the legacy fleet of ageing EC-130H Compass Calls that the EA-37B is replacing.

A Quiet Step Up from the Hercules

The previous Compass Call platform was an EC-130H — a four-turboprop C-130 Hercules, slow, loud, and visible. The new EA-37B is a twin-jet Gulfstream G550, fast, high-flying, and far less observable. It carries the same mission system in a cleaner, longer-range package.

The platform change matters because the modern threat environment has moved well outside the EC-130H’s comfort zone. A Gulfstream at 41,000 feet can stand off from a fortified airspace and jam it from outside the lethal envelope of Russian or Chinese long-range SAMs.

What It Actually Does

The Compass Call mission set is officially “communications jamming, offensive cyber, and information warfare.” In practice, it can:

• Silence enemy ground-force radios so units can’t talk to each other
• Deny GPS over a defined operational area
• Disrupt enemy air-defence command links so SAM batteries can’t be cued by central control
• Inject false signals into hostile networks
• Conduct cyber effects from the air against connected systems

It is the unglamorous side of warfighting — but in the opening hours of any modern campaign, the side that controls the spectrum controls the fight.

Iran Was the Demonstration

Operation Epic Fury included the EA-37B’s first acknowledged combat sorties. Air Force officials have been reluctant to detail what was actually jammed and when, but the operational picture — Iranian air-defence command links going dark before missile batteries could engage — strongly suggests Compass Call did its job.

The new order is essentially Congress writing a thank-you note in nine zeroes.

Sources: Air & Space Forces Magazine, L3Harris press release, Aviation Week.