What did they do wrong (major spoilers)

You've made it sound gewd :)

...cont...
- Scan the planet for lifeforms before touching down. Pretty sure if you can find a planet that can hold human life from YEARS away you have enough tech to perform a few safety checks before you set foot on a strange planet where you are answering what appears to be a DISTRESS call. Epic FAIL!
- Send your entire crew into potential peril, apart from 3 people. Even parents often take different flights so that if one plane goes down the kids aren't left orphans. Captaining 101. Scouts in first!!
- Build an artificial intelligence that is capable of learning and that is physically stronger than you. It's like getting one of those fancy new cars that drive themselves and telling it to run over you a few times. Doomed to fail.
- Send in a second rescue mission. Have you learned nothing?! Your wife is dead, your captain is dead, everyone is pretty much dead, the planet is over-run with nasty things that burst out of people and IT IS NOT GOING TO END WELL. Doff your cowboy hat and wish them well and get the hell outta dodge!
- Give yourselves nicknames, call each other by your last names or go by your military ranking. You know who survives? DAVID. Seriously the minute you switch to first names the xenomorphs will lose interest and clear off. So simple, and so many lives could have been saved.
- Trust anyone with an English accent, especially if it is posh. Evidence: 90% of Disney films and anything Charles Dance has starred in. Voldemort. It's not rocket science people! Posh = BADDIE.
- NEVER announce your intention to kill someone with words like 'You realise I can't let you leave.' Especially when that person is clearly a homicidal maniac who has murdered a whole species for fun and is breeding monsters in his basement. JUST KILL HIM. He who hesitates is lost, even if you are a smug git who can regenerate.

Haha. Great post. I have watched the movie and agree with everything you said. Another wrong doing:

- Walking on a strange planet without any helmet or contamination protection. Seriously, they don't even need xeno virus to kill them, they can easily inhale an Ebola mutation and die from diarrhea.
- Yeah, the "it is okay to look at the egg" is the naivest ever.

[spoiler]https://www.youtube.com/watch?v=IdwPai_1568[/spoiler]

Come on Ridley! Get better writers. Seems like you got everything else right. The characters in Alien and Aliens weren't this stupid (even Lambert had her moments)

Sounds like a good movie. Hopefully it is a continuation of the story in Prometheus. I really want to know where that black goo came from and how the first xenomorph evolved into the xenomorphs that we see in Aliens.