It varies by airline, but many of them explicitly state in their hiring material to not include NFO/Nav/etc (any non-pilot rating or specialty) in the flight time on the application.
With respect to the FAA, I know of some FSDOs many years ago (early to mid 90s) who gave flight time credit to WSOs in 2-seat fighters who were going for ATPs, but those were guys who all ready had FAA pilot ratings in addition to their military Nav qualification. The two that I know of that did this all ready had FAA MEL tickets and were using their "FAA-part 61 equivalent" sole-manipulator-of-the-controls-while-in-an-F-4-or-F-15E argument to justify the time in their logbook. The inspectors bought that, because of their MEL rating, they were "qualified" to act as PIC in the F-4 and/or F-15E (IMHO not a valid argument, but I'm not a FSDO inspector).
Even in that situation, their experience was only being used to fill some of the flight time requirement for the ATP -- they were still taking a full-up ATP practical test to receive the rating.