Frankr -
If someone gave me a free type, a six figure job, and told me that it was me or him that had to take the Xmas trip, I would volunteer for the flight rather then resent that fact that he didn't take the bullet.
And like you said, if you would rather go flying, or rather stay home, then that can be worked out with the other pilots. A good dept manager would probably give that flight to the single guys that would otherwise be depressed sitting around on Xmas alone watching TV. I don't see any resentment other then what you manufactured.