Can I make a suit that will allow the wearer to survive a 40 story fall?

Other than one with a parachute or helium baloon attached obviously.

Is it possible to make a rigid, padded suit that would allow the wearing to survive a 40 story fall unharmed? The suit would be designed to survive the impact (like football pads or those bear suits), not reduce the impact velocity.
CAUTION: Please do not try to test your ideas!!


      • Any suit will survive a 40-story fall just fine. It’s the person inside that gets into trouble. Why are you ruling out parachutes and helium balloons?.. And have you considered jumping from 41 stories?..

I can think of something more like an “apparatus” than a “suit”:

A person enters a rigid (but slightly flexible) spherical cage about 15-20 feet in diameter. Inside this sphere is a torso harness attached in all directions to the interior of the sphere by 64 (or so) taut bungee-style cords.

Any suit will allow the wearer to survive a 40 story fall, provided that he starts falling at least 41 stories above the ground.

It’s not the fall, it’s the sudden landing that will do the damage.

You’ll need something with considerable size, because the only way you’ll survive is if you decellerate slowly over a distance. Consider a cars crumple zone that allows you to survive a 40 MPH crash, it works because you decellerate over those few feet while the car is crumpling.

I suspect bordelond has under-engineered his design, but the principal is good.

That’s how we landed on Mars recently to save money (alot of money actually). Put the lander in a giant inflatable ball and just dropped it. Here’s a pic.

How about something inflatable and incredibly strong, which will

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(along the lines of the gizmo sent to Mars recently)?


That’ll teach me to waste time playing around with my posts … :slight_smile:


I was thinking along the same lines. Airbags that deploy on the way down, but instead of lots of bounce you would want a controlled deflation upon impact.

Cause then there wouldn’t be anything to discuss cause we already know that stuff works.

Here’s some of the thought process behind my question. I’m sitting up here on the 28th floor of my office staring down at the street. Suddenly, I started thinking about those egg experiments where science students create those contraptions for protecting eggs tossed of a building. That led to thoughts of those stunt guys who pack themselves into a car and drop it 70 feet.

Terminal velocity for a human is what? 200 mph. Race car drivers survive that all the time (although not usually head on:( )
I’ve seen pictures of the inflatable ball - makes sense on a planet with lower gravity and atmosphere. I’m wondering if the “suit” would end up being the size of those inflatable balls. I’d have to do some calcs, but it seems like if you had a big enough titanium reinforced foam sphere, it might be survivable.

Well, Fat Bald Guy done stole my observation. The fall isn’t the problem. It’s the sudden stop at the end.

Therefore, if we can eliminate the sudden stop at the end, we can eliminate the damage. An ordinary business suit will save you from a forty story fall, so long as you land on an air bag. The air bag doesn’t STOP the fall, it just SLOWS YOU DOWN rather suddenly, so as to avoid the SUDDEN IMPACT and resulting hydrostatic shock.

Therefore, a suit made of some sort of foam padding could theoretically do this.

Admittedly, the padding would have to be fairly thick. In fact, looking at your average forty story building, I’m inclined to think that this suit would pretty much preclude ANY activity aside from jumping off buildings. In fact, you COULDN’T jump off, not if the suit were going to be safe to land in from any angle. You’d have to be PUSHED off…

Yes; suppose you had some super-foam material and encased yourself in a suit of it that was a foot thick - ignoring the obvious fact that this might slow your descent due to wind resistance, when you get to the bottom, you still have to decelerate from whatever velocity to zero in the space of a foot (the thickness of the padding, give or take).

Clearly (as Wang-Ka says)the suit is going to be so thick that it won’t really be suitable for the office.

A trailing streamer can be almost as effective as a parachute in some cases, perhaps you could deign a suit that rearranges itself into a series of long ribbons.

Terminal velocity for a human is ~120 MPH (53 m/s )

Lets say that you want to decellerate at max 10g (not pleasant, but survivable).

so going from 53 m/s to 0m/s at 100 m/s^2 (or 0 to 53)
v^2 = v0^2 + 2ad
2809 = 0 + 200d
d = 14m
(or use d = (v^2-v0^2)/2a +x0)

So, if the suit is 14 meters thck it would work. Tho a suit 14m thick (and will compress completely) will probably reduce your terminal velocity, and you can probably up the g force some also, so the suit can be thinner.


Well, something like Iron Man’s “Hulkbuster” armor came to mind, right off the bat…but that’s assuming that the armor would be 2-3 times the size of the person who “wore” it, that most of the suit’s mass was basically an anthropomorphic “crumple zone,” and that the suit would have very little (well, make that “absolutely no”) freedom of movement.

If you fell 40 2m stories you wouldn’t reach terminal velocity. At most sqrt(21080)=40m/s. But less than that as air resistance must become non-negligible. If it was 30, your suit would be 5m think (30^2/2.100). Still too think, of course.

Anyone know how think those big fire department air bags people fall onto are?

Not entirely related, but worth a look. This eccentric Canadian has spent the last 15 years designing a suit that can withstand a bear attack.

Seeing as people (a race car driver in particular I think) have survived 100+ G stops, I think it’s safe to reduce N9IWP’s calculations by a factor of 10, meaning it could require a suit as little as 1.4 m, or 4 ft, thick.

Thanks for that link. You saved me some googling.

I saw that guy on one of the tabloid shows a few years ago. The suit looks pretty cool. He was hit in the chest with a swinging log and he was hit by a car going rather fast. He was uninjured.

Myabe a suit like that could do it. Probably not, though.

The Mars Pathfinder also used a parachute. Older landers also used parachutes, but at the last minute they turned on their rocket engines for a soft controlled touchdown. The Pathfinder used the inflatable airbags to soften the final jolt, and righted itself after it came to a stop.

By the way, science fiction novels often use “acceleration tanks” to help people withstand high acceleration. The theory is that if you are immersed in a saline solution, the acceleration will work on your body evenly and there will be no concentrated stress to break bones or organs. Anyone know if this works in practice, and whether anyone has tried it?