“The military branch that operated the P-47 and initially expressed skepticism about its design.”

“The American air arm that initially resisted the Mustang in favor of the P-47 and P-38.”

“The aerial warfare service branch of the United States during WWII.”

“The military branch Hoover served in during WWII.”

“The military branch Ilfrey served in; they updated their training doctrine based on his flight.”