# Which body position causes the least amount of negative acceleration? [closed]

Let's say you are in the air 500 meters above flat land and you have no parachute. Which pose - forming a sphere or spreading all extremities to make yourself as wide as possible or other - is the most appropriate to cause the highest likelihood of survival?

1. in the air
2. right before impact

In other words: which body position causes the least amount of negative acceleration in this context?

PS: As a side-question: Which body position enables you to control the direction of flight to control your angle of impact and make it as flat as possible?

My take: In the air make yourself as wide as possible and control direction by weight displacement. Right before impact, form a sphere when having a flat angle of impact and let rolling take care of the change of kinetic energy into heat and potential energy.

• My take: you're going to splat no matter what. I don't really think you can control your angle of impact much and curling your body into a ball isn't going to help or make you roll because at that velocity you're pretty much a sponge of meat saturated with water. Commented Feb 7, 2014 at 0:42
• My take: don't go jumping out of an airplane without either a parachute or a wingsuit because it will end very badly for you otherwise. Commented Feb 7, 2014 at 1:20
• Debatable. Besides, your question isn't really answerable. You really think someone could roll after curling up in a ball? I mean, you do realize that you'd be traveling at terminal velocity of roughly 130 mph? You don't roll, you go splat. Commented Feb 7, 2014 at 1:31
• Actually, an easy inference from the comments given: you have a 0% chance of surviving regardless of posture because you'd go from ~130 mph to 0 mph in less than a second (force of a few hundred thousand Newtons). Commented Feb 7, 2014 at 1:55
• This question appears to be off-topic because it is about optimizing a complex system where all realistic outcomes are suboptimal (death). Commented Feb 7, 2014 at 2:33