Does a strong wind slow down your free fall?

[ksg00]

I was wondering do strong wind slow down or has any effect on the outcome of your free fall? Like slower down your impact or help you survive?

Hypothetical, you free fall down height of 1,000 feet below are just rocks so hard surface (not water). Basically it should cause death.
But let say that day there strong wind, you free fall down 1,000 feet below, wouldn't the wind have any effect on the speed you free fall down? Like slower down the impact? Chances of survive more? (even at 1,000 feet?)

Thanks.

 

[.Scott]

In a word, no.
Your terminal velocity (wind velocity) will be somewhere between 120 mph (spread eagle) to 200 mph (dart-like nose dive). Experienced sky divers can also track - moving as much as 1 foot horizontally for every 2 feet down.

You jump from 1000 feet will just barely get you to terminal velocity - so you're probably talking closer to the 120 mph than the 200 mph.

When people have survived that kind of fall, it is because of what they fell onto (a row of plowed dirt, sand, etc) - not the wind speed.

The key reason that wind cannot help you is that the closer you get to the ground, the closer the vertical component of the wind speed is forced to zero. At the surface, the wind blows horizontally - so it can only add to your speed.

 

[ksg00]

In a word, no.
...

ah thank you Scott for help me, I'm very sorry I'm not good at physics and I easily get confuse. Me and my friend keep debate about this, as how strong wind can help you survive, same as snow can help you survive, etc..

And we talking about a location free fall 1,000 feet like this location pic below:
So chances if you free fall straight down there, regardless of strong wind, as long as you hit the bottom down there, very unlikely to survive right?

And me and my friend were debate about all those rocks there, so let say when you free fall down, you hit your head or body on the edge of those jagged rocks, then continue free fall down, wouldn't by hitting your head on those rocks help reduce the speed and impact?

We just debating survive a free fall from a place like this height of 1,000 feet.

 

[anorlunda]

In theory, yes. I disagree with @ksg00 . For example, indoor skydive simulators such as this.

In practice, no. I agree with @ksg00. You will never find a vertical wind in nature like the one in that simulator. I am neglecting fantasy scenarios like tornadoes that will lift you from Kansas to Oz.

Slowing your descent by bashing your head on the rocks is a novel approach. It reminds me of years ago driving in Syracuse, NY when I learned to control my car speed without brakes going down steep slippery hills by bouncing the car off the snow banks on both sides. But my car's bumpers were more rugged than my skull.

 

[davenn]

I am neglecting fantasy scenarios like tornadoes that will lift you from Kansas to Oz.

you don't think tornadoes lift things up ?

 

[Bystander]

https://www.physicsforums.com/threads/do-surfaces-ahead-of-propellers-decrease-thrust.976424/

 

[ohwilleke]

In a word, no.
Your terminal velocity (wind velocity) will be somewhere between 120 mph (spread eagle) to 200 mph (dart-like nose dive).

Assuming that you are at a low end 120 mph, a good crude back of napkin approximation of the benefit of the upward wind (it isn't rigorously correct, but is reasonably close) is to break the wind into vertical and horizontal components of direction and then subtract the vertical component from the 120 mph (assuming that the vertical component is blowing upward, if it is blowing in the other direction it hurts, rather than helps).

Based upon automobile accidents, death is pretty much certain at 50 mph, and very likely at 40-45 mph. So, you need a 70-80+ mph upwind to have even a prayer of surviving. Canyons do tend to have up drifts (which birds love to play in), but typical canyon up drifts are rarely even as strong as a gale force wind (32 - 63 mph ). An EF-0 tornado is 65-85 mph.

So, short of a tornado and not just an even unusually severe upwind, you die. And tornados just do not happen in tight canyons like this one, they tend to form on comparatively flat open surfaces with lots of space to build up. Your best shot is to bang into the side of the canyon long before you hit terminal velocity. A very strong crosswind could do that.

 

[ksg00]

So is PP saying that if free fall down that pic I posted above, best shot of survival is hit your body on those jagged rocks first so it can break down your impact as you continue free fall down? That help you survive? Well, it not like you can control how your body going to land or what to do hit once you fall.

 

[ohwilleke]

So is PP saying that if free fall down that pic I posted above, best shot of survival is hit your body on those jagged rocks first so it can break down your impact as you continue free fall down? That help you survive? Well, it not like you can control how your body going to land or what to do hit once you fall.

Not sure who PP is ("previous post", i.e. me?), but I would agree that the best shot of survival is to hit your body on those jagged rocks first, at as high an elevation as possible, so it can break down your impact as you continue to free fall down (if you are almost all of the way down, hitting the water or mud adjacent to the river would probably be better).

You can have some slight impact on what direction you fall, you could get lucky with crosswinds, and you might push off towards a rock wall as you leap or are pushed off.

Going into the water might be a good idea in some circumstances, but this particular river (which appears to be the Arkansas River where it runs under the Royal Gorge bridge in Colorado) is quite shallow and if you are seriously injured but not dead on impact, you might drown because you can't swim while so badly injured.

This said, basically, you are dead and there really is very little that you can do. On average, about one person dies per year in this fashion at the bridge shown in the image, and I'm not sure that anyone has ever survived with fall without a bungee cord or BASE jumping equipment, neither of which are usually allowed. In addition one person died in 2003 with such equipment after impacting the bridge itself at 120 mph in stunt and then landing on a ledge.

 

[anorlunda]

I think we did what we can for an engineering answer to the OP.

Thread closed.