If you get something "airtight" be aware of the fact it will swell when the airliner is at cruising altitude, and will compress again during the descent. This is when your ears are popping and the babies are screaming in agony. When you hear them screaming, think of your case and try to remember if you've opened a vent.
Even worse, is what can happen to your Phantom. Some cases will allow air to escape, but not enter the case. This alleviates the "swelling" of the case, but screws you royally as the cabin pressure rises during the descent. That's when the case will actually shrink,
which may crush the contents.
The
WORST possible thing you could do, is to
let the extra air out of the case while the airliner is in flight. If you must do this, you must also leave it open, or it will crush your Phantom.
It's a good idea to open at least 1 vent on an airtight case for the duration of the flight to prevent damage to the contents.
There you go jlo, hope that helps.
For those of you wanting to experiment, take an empty plastic water bottle with you and let the air out while the airliner is at cruising altitude and you will get to watch it being crushed during the descent.