But what about not being conscious to open it yourself?
That's what happened to a skydiver in Wiltshire, England in July 2013 in an incident that was captured on video and obtained by ABC news this week. In the video below, 25-year-old James Lee is knocked unconscious when another jumper's leg hits him in the back of the head in midair.
Then, after some of the other jumpers sensed that something was wrong, they tried getting Lee to respond to hand signals. And after he didn't, they safely positioned his body and pulled his parachute.
Skydivers fall at an average of about 120 mph, and Lee jumped from about 12,500 feet.
It's easy to see how this could have turned into a catastrophic mishap, but thanks to the quick thinking of Lee's fellow jumpers, no one is writing that story.