I know that color timing and real life colors are two different things but judging from the first screen grabs where we see Dallas around the table wearing the jacket and since I owned that RAF jacket I can tell you that the colors on bluray are the most faithful to real life (perhaps just a tad brighter), DVD close enough, laserdisc colors are completely off.
Just a curiosity for you guys. Great job here. I didn't know there were so many different "color versions" of the same frigging movie!
That's right to a certain degree and wrong to a certain degree also.
Its always good to have this discussion. Unless someone has access to a non-faded print from 1979 (not just the negative which would not have final color timing), we will never know the true colors. And finding and scanning a non-faded print from the 70s with the bad Kodak film they had those years would be difficult.
Opposed to the the RAF jacket, you could also focus on the Nostromo model which is tinted blue in the BD. Having seen pics of the model I can say that's wrong. It was gray colored similar to the way it looks in the LD and 99 DVD. Like he said life and film are different.
I can't say the LD is the definitive color palette of Alien. I can't say that it is "right". All I can say, is that there is some evidence that it may be "righter" then the BD in certain spots. Jonno's scans, the fact it looks more 70's, etc. If it helps, treat it as a fun alternative to the BD and not the definitive version, that's what I'm doing.
I can also say the BD is not right either. In fact the more I watch, the more I start to see all the strange color inconsistencies. Look at the Ash head scene in that youtube clip I posted. In the BD white, in the LD blue. But the BD also has scenes with the back of Ash's head having a blue tint when shot facing Ripley. Did they forget to correct the blue out or did they put it in by accident? Or this, the BD and LD both have a orange/red tint:
BD/BD with LD Colors (Ignore the framing, I did this quickly)

But then the BD immediately loses it, tending more back to white for the helmet:

Then gains the tint back for a close up of the grappling hook and loses it again right after:

Very strange. It matches the LD pretty well in those tint scenes. Then goes its own way on a whim. Maybe instead of intentional, we have hit the era of lazy color correction.