Bizarre Question: High-Speed Humanity

SirNitram · Post by **SirNitram** » 2003-04-03 09:43pm

Alright. This is a wacky one: What sort of ill effects come from high speed, for humans? Assuming, for a moment, the human in question is capable of unusually high acceleration and can react fast enough to take advantage of such, what speeds would cause what ill effects? Could they reach a point where they are effectively getting 'rug burn' on exposed tissue from air friction? Would their internals liquify first?

Morat · Post by **Morat** » 2003-04-03 09:47pm

Could they reach a point where they are effectively getting 'rug burn' on exposed tissue from air friction?

Of course. Thanks to relativity, anything can travel at any speed without ill effects (as long as it has protection from the environment).

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-04-03 09:49pm

When the outer dermal layer of your body is peeling off due to frictional heat, I think that's too fast.

SirNitram · Post by **SirNitram** » 2003-04-03 09:50pm

Admiral Valdemar wrote:When the outer dermal layer of your body is peeling off due to frictional heat, I think that's too fast.

Exactly. But what speed is that?

Post by **Darth Wong** » 2003-04-03 10:15pm

At Mach 6, aircraft fuselages begin to melt. So obviously, the speed limit would be somewhere below that

As for acceleration, the limit for remaining conscious is about 9 G's IIRC constant (Wicked Pilot would be the expert on this, I imagine) and a few hundred G transient (I think it was 400G, but don't quote me on that), so anyone who accelerates an entire body in a manner that exceeds those numbers is going to knock himself out and possibly cause brain damage.

Montcalm · Post by **Montcalm** » 2003-04-03 10:22pm

SirNitram wrote:
Admiral Valdemar wrote:When the outer dermal layer of your body is peeling off due to frictional heat, I think that's too fast.
Exactly. But what speed is that?

I suggest you experiment that,first go strap yourself on a high speed train,and if nothing happen go for something faster

Post by **Sea Skimmer** » 2003-04-03 10:26pm

Darth Wong wrote:At Mach 6, aircraft fuselages begin to melt. So obviously, the speed limit would be somewhere below that

That depends what there made out of, many aircraft skins will melt at around mach 3. That's why the MiG-25 was made out of steel.

As for acceleration, the limit for remaining conscious is about 9 G's IIRC constant (Wicked Pilot would be the expert on this, I imagine) and a few hundred G transient (I think it was 400G, but don't quote me on that), so anyone who accelerates an entire body in a manner that exceeds those numbers is going to knock himself out and possibly cause brain damage.

Conscious and acceleration limits are dependent on the time involved. In general its felt that 9 G's is the maximum that can be sustained, though you will be getting tunnel vision at the very least. However some aircraft can pull as much as 13.4 G's for a few seconds without a pilot blackout.

400 G's sounds right for brain damage.

SirNitram · Post by **SirNitram** » 2003-04-03 10:48pm

Darth Wong wrote:At Mach 6, aircraft fuselages begin to melt. So obviously, the speed limit would be somewhere below that

Indeed. I didn't plan on exceeding the sound barrier.. The shockwave would do bad things to those surrounding the poor guy, but it'd get them off his tail.

As for acceleration, the limit for remaining conscious is about 9 G's IIRC constant (Wicked Pilot would be the expert on this, I imagine) and a few hundred G transient (I think it was 400G, but don't quote me on that), so anyone who accelerates an entire body in a manner that exceeds those numbers is going to knock himself out and possibly cause brain damage.

Wow, 400G's for brain damage? I'm amazed. I think I can safely peg his natural acceleration below that, though. Do you have any idea of a human could have been genetically 'tweaked' to withstand more than 9G's?

And I'm still trying to figure out what speeds will signifigantly degrade human skin, and then fabrics. The steel figure is nice, but I doubt he'll be suiting up in full plate then outrunning attack jets.

aerius · Post by **aerius** » 2003-04-03 11:00pm

SirNitram wrote:Wow, 400G's for brain damage? I'm amazed. I think I can safely peg his natural acceleration below that, though. Do you have any idea of a human could have been genetically 'tweaked' to withstand more than 9G's?

Make the human female. As I remember it females have a higher G tolerance than males.

Montcalm · Post by **Montcalm** » 2003-04-03 11:07pm

aerius wrote:
SirNitram wrote:Wow, 400G's for brain damage? I'm amazed. I think I can safely peg his natural acceleration below that, though. Do you have any idea of a human could have been genetically 'tweaked' to withstand more than 9G's?
Make the human female. As I remember it females have a higher G tolerance than males.

Thats good someone had to brag that female are tougher than male.

Post by **Darth Wong** » 2003-04-03 11:12pm

Wow, 400G's for brain damage? I'm amazed. I think I can safely peg his natural acceleration below that, though.

Keep in mind that this is for a transient that lasts for milliseconds (think of a punch to the head rather than a constant acceleration).

Do you have any idea of a human could have been genetically 'tweaked' to withstand more than 9G's?

The body isn't the problem; it's the brain. And if you significantly change the brain structure, one would have to wonder if the resulting creature is still classifiable as human.

And I'm still trying to figure out what speeds will signifigantly degrade human skin, and then fabrics. The steel figure is nice, but I doubt he'll be suiting up in full plate then outrunning attack jets.

Human skin can survive 300 mph winds; I've seen pictures of test subjects in wind tunnels. But Walmart-grade clothes would probably be ripped or torn at that speed.

SirNitram · Post by **SirNitram** » 2003-04-03 11:18pm

Darth Wong wrote:
Wow, 400G's for brain damage? I'm amazed. I think I can safely peg his natural acceleration below that, though.
Keep in mind that this is for a transient that lasts for milliseconds (think of a punch to the head rather than a constant acceleration).

I had wondered about that. Okay.

Do you have any idea of a human could have been genetically 'tweaked' to withstand more than 9G's?
The body isn't the problem; it's the brain. And if you significantly change the brain structure, one would have to wonder if the resulting creature is still classifiable as human.

The ficitonal character I am making doesn't consider himself human, though this is largely for other reasons. But I was under the impression the blackout point was due to lack of circulation at those speeds?

And I'm still trying to figure out what speeds will signifigantly degrade human skin, and then fabrics. The steel figure is nice, but I doubt he'll be suiting up in full plate then outrunning attack jets.
Human skin can survive 300 mph winds; I've seen pictures of test subjects in wind tunnels. But Walmart-grade clothes would probably be ripped or torn at that speed.

Thanks again, this looks like it'll all be very useful. Most of the acclerations probably do fall under transient, but this is all very handy.

Captain tycho · Post by **Captain tycho** » 2003-04-04 12:43am

PS, The highest safe G limit is nine. Any higher and your brain dead.

Shaka[Zulu] · Post by **Shaka[Zulu]** » 2003-04-04 02:26am

aerius wrote:
SirNitram wrote:Wow, 400G's for brain damage? I'm amazed. I think I can safely peg his natural acceleration below that, though. Do you have any idea of a human could have been genetically 'tweaked' to withstand more than 9G's?
Make the human female. As I remember it females have a higher G tolerance than males.

actually it is principally due to heart-brain distance... the farther they are apart, the harder the heart has to work to get O2 to the brain -- eventually it cant do the job no matter how hard it works. women, being substantially shorter on average than men thus have a distinct advantage as a group. The abdominal muscles also play a role, as women tend to be stronger in that region than the average male to facilitate childbearing, but that advantage can be easily overcome by strength training, which men respond to more readily.

Sriad · Post by **Sriad** » 2003-04-04 03:54am

Darth Wong wrote:
Do you have any idea of a human could have been genetically 'tweaked' to withstand more than 9G's?
The body isn't the problem; it's the brain. And if you significantly change the brain structure, one would have to wonder if the resulting creature is still classifiable as human.

At some point isn't there also damage done to other important internal organs, like hemorhaging and stuff? This is on the "I recall reading somewhere" level, but I think at some point the tissues that hold organs in place in the body can tear and bad things happen, this is how a lot of car accident/fall victims die, not because of the sudden stop, but because their skeleton and muscles have stopped, but their internal organs try to keep going.
Food for thought.