It doesn't make any sense at all. The chances of being in a situation where you need one are infinitesimally small. The chances of being in a situation where yo

It doesn't make any sense at all. The chances of being in a situation where you need one are infinitesimally small. The chances of being in a situation where you need one and it is safe to use one and still having the presence of mind (and time) to find it, put it on and properly use it are even smaller. If you want to make air travel safer, demolish all the roads in town and have everyone walk to the airport. You're much more likely to die on the way there.