With a good safety record and robust backup systems, the Airbus 330 wouldn't be easily downed by lightning, they say.
At least 34 countries have plans, worth a total of $2.25 trillion.
The new process will be as transparent as possible, said defense officials Wednesday.
The Air Force should reopen the bidding process, the Government Accountability Office said Wednesday.
The shift reflects consumer stress, but it could help boost US manufacturers.
The Air Force's $35 billion award to a European aircraft company is one of its largest ever.