I know of guys that got hired with suits of all (normal) colors. That includes grey (gray?), blue, dark blue that's almost black, black and even a guy in an olive suit with wine colored shoes and a tan shirt. One guy that got the nod even wore a short sleeved shirt under his black suit jacket, which they saw when he took his jacket off in the sit down portion. He was also hired.

Oh, and ties of all (normal) colors too. I think the key is wear what you want, as long as its somewhat conservative and mainstream, and it needs to look good and look good on you. Proper fit, pressed, no lint, and newish well shined shoes. I'd also not skimp on the belt or briefcase, although I know of a couple that got on with very ratty cases, but why introduce that element of risk if you don't have to?

That's not to say you need to go out and buy top shelf everything including $500 brief cases. Far from it. Pilots have been hired wearing suits off the $99 sale rack carrying bottom shelf office depot brief cases.

That said, most of the pilots on interview day will be in dark blue suits, white shirts and red ties with new brief cases. Therefore most pilots hired will be of that profile. That doesn't mean there is any preference either way on Delta's part. But it doesn't mean there's not either…

Whatever you wear, it needs to fit and look good and you need to carry yourself well and jump through all the other well gouged but homework intensive interview hoops. I really don't think the forum uniform profile is the new rocking chair conspiracy like some seem to think it is. I just wouldn't stray too terribly far out of the circle of social expectations with your dress code if I were you. Just look good, that's the main thing.

Cause DL pilots look good. All of us.