He has Tesla's "Full Self Driving" system, which works with AI and cameras.
He probably wants to just upload his software to US fighter jets for, say, $20 million per unit.
It might actually cost way more than that, changing the jet's balance and attaching things to them requires major modifications, but him selling the the systems for that alone sounds about right.
Maybe the real plan is to intentionally fuck it up and weaken the US Military. Wouldn't put it past the Trump admin.