What If the Door Comes Open During a Flight Lesson?

Answer: As with most training aircraft, your Pipers, Cessna 100 series, Cirrus SR20/22s, and Diamonds are not pressurized, so there won't be an “explosive decompression.” That's not to say it won't be loud and startling if it happens. It will.

The most important thing to remember is to fly the airplane, especially if it happens on takeoff. Don't try to reach over and close the door. If you have a runway ahead of you and can safely land, do so. If you are out of usable runway, fly the pattern and return for landing. Once you are safe on the ground and at a full stop, close the door. If you are at a towered airport, letting ATC know you have a problem can be beneficial as it will likely give you priority if able. As far as declaring an emergency, if you feel your life is endangered, then do it.

You won't be sucked out of the airplane if the door pops open, since you're wearing your seat belt, per FAR 91.107, aren't you? That’s not to say loose objects like sunglasses, cellphones, or sectionals won’t get pulled out. Arrange your cockpit accordingly to prevent this from happening.