From Top Gun (the movie) Aboard Enterprise, Iceman and Hollywood are assigned to provide air cover, with Maverick and RIO Merlin on standby. Iceman expresses his concerns to Stinger about Maverick's mental state, but is told to just do his job.1
As he thinks Maverick isn't a good fit for the job, it's pure conjecture to choose the exact words, but you can for sure end the sentence with almost anything that conveys that idea (it's only pure basic english language here, I believe):
is he the best backup that...
- we have?
- you can pick?
- we can expect?
It's not written in the scripts I could read: section 117C - scriptorama (where the line is "- But is Maverick the best pilot to ... ?")
After more research I found another version of the script where it's written:
Nothing personal Sir but is that the best backup you've got?
1. emphasis mine