I'm a 5'2" and 98 pounds. I can't even donate blood, but I would fight like hell until I couldn't move. I would try to do my part in organizing my fellow passengers. I have something in mind like passing a message through the rows, something like "get up when I scream/cough/sneeze/stomp/whatever." Then, I would occupy one of the bad guys with me. I've trained in martial arts and self-defense for several years, not that I think this would give me an advantage, since there would be such a size/strength discrepancy, but it might prolong the altercation a bit, and I might just get lucky and be able to scratch out an eye or something. Pre-occupying a bad guy with me would give others a one-up -- even if just for a few seconds. Hopefully, they would realize the opportunity and take advantage of it.
Of course, at this point in my life, I don't have children. My perspective might change once I was a mother; I might be reluctant to take a leadership role, but I would probably still participate on ganging up on the bad guys. I look at that as my duty to my fellow passengers and to the leaders. They'd be looking to everyone for support and depending on the strength in numbers. Even when there are as few as 60 of "us" and as many as 5 of "them," the odds are in the passengers' favor, even if the bad guys have firearms.

For all of us frequent flyers, we should get certified in CPR and first aid and put together plans on what we would do in any type of scenario that we can conceive of. Have a plan ahead of time, and that will help hopefully with the shock.

Of course, not everyone will see things this way. Many people have forgotten what America is all about and now expect others to take care of them. We have to take care of ourselves, we have to have confidence, trust, and the highest expectations in ourselves and our neighbors. We have to do everything it takes to defend ourselves our rights, and our neighbor's rights. We owe that to ourselves and our society. This all sounds corny, but it's true, and so rarely considered these days.