Planes

SO. i always have wondered how planes stay up. I mean, i've heard all the crazy stuff about lift and drag and whatever, but um................ planes are big. Very big. Too heavy for the skies. Hmmm. Maybe that whole system is asking for disaster. Or maybe i should just never be a plane builder person. I'd probably forget to put in the engine. And even though i don' know anything about making planes, i'm pretty sure a no- engine plane would make people nervous.