Do not call in SICK for your non-sick occasion.

Do call in 'unavailable for work'.


You won't have any sick time accrued, so its going to be unpaid time off anyway.
Do let the recruiter know you have a long-standing obligation for the summer. Do not accept a class date that will conflict with your dates. It sounds as if you should be done with training prior to your wedding day. Let your Chief Pilot know as soon as you get to your base. If the CP won't work with you to arrange an unpaid leave before the fact, make your best effort to cover your time off - swap off days with reserve days, get coworkers to pick up days, however it works at your company. Then call out as needed.

If you get fired anyway after being upfront with everyone, and doing your best to cover the time you need, then to he11 with 'em. Family comes first. And it won't be a black mark on you at any decent outfit.