This was a key consideration for me in selecting a fixed blade; I wanted something that could be useful in a survival situation but that didn't come with a large weight penalty. I think that for most situations (I won't talk to the aircraft scenario because I don't know enough about it) a compromise can be found that is light enough to carry and tough enough to be a very useful survival tool.

For example, when I was looking the Becker Companion, by all accounts, it seemed like a perfect survival knife but the weight killed it for me. Now, my F1 can arguably do everything that Becker can and comes in at 1/3 of the weight. It's a great compromise between capability & weight; if I ever find myself in a situation where it is my only tool I don't think I could ask for better.

Personally, I have no use for a blade that I won't be carrying.