We both fly and camp alot. I have different requirements for each. For flying I need to pack a gluten free snack. I usually end up packing bars that I can eat on the way or save for breakfast one we get to our destination. You have to be careful though when you fly they won't let you take anything that isn't sealed.
For camping we always have packages of sausages. We love sausages roasted on a campfire. We also take mustard, salt, hot sauce, bread for DH, fruit, tomatoes, onions and cucumbers, cream cheese in a tub for toast, chocolate, marshmallows, pop and a couple bottles of wine. I would cook more but I have no interest in doing dishes while I'm camping so until DH decides he wants to do the clean up this is our usual menu. We like it anyway.