I'm just at the final stages of a similar dismissal in my job (not related to flying in any way) and the hoops an employer has to jump through are numerous. employees today have so many rights.
I have bundles of notes, emails and everything that ever been said between myself and the employee and still the solicitor is nervous to make sure everything is covered.
We've had to try and offer alternative positions to the employee to show we have done everything we can.
Each meeting brought out another matter and then we had to have another meeting to discuss that and so on....