I believe the notion that "if the plane crashes, you die" is a myth. Even fatal airline crashes usually have at least one survivor; in the Sioux City disaster, almost two-thirds of the passengers, and all but one of the crew, survived, even though the jumbo jet was nothing but a big ball of flame tumbling end over end down the runway.

I can think of a couple of airline crashes where there were no fatalities. I read about one in Alaska where the turboprop plane lost both engines due to ice crystals in the fuel line, and had to land on a frozen lake. Passengers and crew evacuated the aircraft and had to walk half a mile to shore in temperatures of -30. Fortunately, it was pre-9/11 and the passengers were mostly oil-rig workers on their way back to work, so everyone was "dressed to survive".

There was an Airbus "computerized" plane that went down in the Alps when one of the pilots typed in a 3.0 degree slope on the computer, not realizing that it was a "dual-purpose display" which also controlled the rate of descent. In that mode, what he had actually done was to type in a descent rate of 3000 feet per minute. Since the only indicator was a tiny red light and the absence of a decimal point, needless to say they weren't able to figure out their mistake in the 75 seconds they had left before hitting the side of a French Alp. (I understand the flight deck instruments have been redesigned since then. ;-) )

It took authorities several hours to find the crash site; in fact, it was a reporter for a local radio station who found the site and called for assistance. Quite a few people survived the crash, although many were badly injured; I believe several of them succumbed to the freezing temperatures waiting for rescue to arrive.

I think the chances of ever being involved in an airline crash of any sort, let alone something like the above, are so remote that I can safely leave it off my list of "the top 100 things I worry about dying from". But I have a key on my keyring which is a blank, with five Ronson lighter flints crazy-glued to it, and a short length of clear plastic shrink tubing around it. The key fob has a steel attachment which will strike a spark, and I have a laminated first aid card in my wallet with two or three cotton balls laminated to the back of it (almost invisible against the white card, as it turns out). I've taken these through security maybe a dozen times, and no-one has ever given them a second glance. (I don't do it to "fool security", by the way - it's simply a convenient way for me to carry a basic fire-starting kit on an everyday basis.)

You can also get a small bottle of that alcohol-based hand sanitizer stuff (Purell, or one of the knock-off brands) which is pretty good firestarter and will probably make it through with your perfume/aftershave, toothpaste, and shaving cream in a 1 litre plastic back. I haven't tried that, though.