Almost all airplanes are made with just stringers and covering on the bottom. You have to be careful where you lift.

It's made worse on a big plane becauise of the weight, you generally need 2 people to handle them. This is the main reason that I don't fly the 40% size planes, I am normally by myself and I just can't manage a 40%er into and out of my vehicle without doing some kind of damage.

TF