An instructor teaching a group of students how to clear a room using a hand grenade underestimates his strength and goes on a quick flight. No one was seriously injured in this grenade fail.

If you're going to teach your guys how to toss a grenade into a room, you should probably make sure you know what's going to happen when the grenade explodes. Otherwise, you'll end up in a video on Funker530 with the tag "Grenade Fail" attached to it, and you'll probably never live it down for the rest of your life.

The good news is, no one got seriously hurt. The bad news is, this guy's ego will never recover.