HUGE alien ship error!

I think your thinking about that too much, compared to the other crap happening

good catch, but why is this an issue...? so it ended up upside down

Who knows.... Untill we drop large scale models we wont know for sure which way it would land, it could be a case of heads or tails... I think they went for it to land the way it did, purely to get the audience to wonder..... "could this be the ship thats in Alien and thus LV 426 is LV 223" While thats not the case the movie had many moments that dropped hints to make us assume that many things could potentially had lead to Alien it was done to fool us all and i think the Xeno at the end is likewise and will never have anything to do with the creation of the Alien Eggs in Alien.

Didn't the film show David's head on the cieling of the cockpit after the crash? I think they thought it out correctly.

The ship is clearly shown on the ground right side up. (funny thing about David's head.. after all that crashing and rolling, and it's still sitting on the floor right there next to his body!)

LOL - I don't think it much matters which way up it fell, it won't have changed this film one bit.

Maybe David crawled over to his head and attempted to reattach it while the engineer was flying the ship. Maybe David was desperately holding onto his head while the ship is crashing? Maybe it was just luck that his head landed next to his body? Who knows? Its not a big deal and these things happen all the time in movies.

Maybe the ship inner parts run on a gyro and can right inself from the inside. If you look at some of the corridors, the ceiling, walls and floor all look the same...meaning that you can walk on any of it...