The reason is physics. Steam catapults generate enormous magnetic fields during operation. These fields are catastrophic for the sensitive electronic components and unshielded avionics inside Unmanned Combat Aerial Vehicles (UCAVs). Electromagnetic catapults (EMALS), by contrast, can be tuned to provide smooth, controlled acceleration without the electromagnetic spike that fries drone circuitry.

The Stranded Allies

Worse, the decision strands every allied navy that planned to follow the American lead. France, the United Kingdom, Australia, and Japan will now have to develop their own EMALS systems from scratch, given that the USN has already spent 20 years and billions on a program it now treats as failed.

The magnetic reality is unforgiving. A steam shuttle slams a 30 ton aircraft down a track in seconds, and the inductive kick of that discharge blankets the deck in a field that no commercial grade drone bus can survive. EMALS solved this by spreading the impulse across the full length of the stroke, lowering peak field strength to a level the airframe tolerates. Walk that back, and the loyal wingman becomes a hangar piece.

For the allies, the question is left with no answer: who launches the drones if the lead Navy will not?