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Riding a motorcycle on a freeway at over 200 kph you surely feel the rush of air around you. A typical commercial jet airliner travels at approximately 3-5 times that speed at cruise altitude. Assuming you could open the cabin door closest to the wing fuselage and step out on to the wing, does the air rush feel more 3-5 times more intense than if you were on your bike? Does it mean there is more air resistance to blow you off if your bike could travel that speed? If so, then what would be required to secure yourself to the aircraft in order not to be blown off from the air velocity around you, again assuming that air temperature and thickness of air to support human consciousness isn't a factor?

Then there is a issue of cabin depressurizing, but again assuming this is ignored or resolved through pressure equalization with the outside pressure (oxygen masks will need to be worn by the rest of passengers inside for survival)

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    $\begingroup$ There actually was a stunt person who rode around on top of a DC-8: latimes.com/visuals/photography/… Admittedly, this was at low altitude, and much less than cruise speed. $\endgroup$ – jamesqf Apr 3 at 3:09
  • $\begingroup$ If you were on the wing then you would affect the aerodynamics, increasingly so as you move away from the fuselage. At some point the extra drag and loss of lift will exceed control authority, and I don't think you would need to be very far out before that happened. $\endgroup$ – Paul Johnson Apr 3 at 8:47
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    $\begingroup$ Wing-walking at 4,000 feet youtu.be/23vGNEJU15M?t=891 $\endgroup$ – chasly - supports Monica Apr 3 at 9:37
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    $\begingroup$ This is a classic dramatization that I'm sure is scientifically accurate: en.wikipedia.org/wiki/Nightmare_at_20,000_Feet $\endgroup$ – Ben Crowell Apr 3 at 13:43
  • $\begingroup$ @PaulJohnson I expect that long before that became a problem, you would simply lose your grip and fall off. Unless you were some how tethered to the wing; there's no human strong enough to hold on in those circumstances, contrary to a number of ridiculous action movies I can think of. $\endgroup$ – Darrel Hoffman Apr 5 at 14:56
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A LOT of wind

3-5 times the speed, means 9-25 times the drag, as subsonic drag scales roughly with square of speed.

Multiply that by the relative density of air at your cruising altitude.
For 30000ft, that is 37.5%

So: You would feel 3.4 - 9.4 times the wind drag / air rush.

You might also notice the difference in wind chill factor.
The -45C air will feel like -105C due to wind chill.

Not that it will bother you for very long:
Before the air buffeting knocks you out,
Before the blast of cold air freezes you like a popsicle,
You will pass out from lack of oxygen.
30000ft has insufficient oxygen to sustain consciousness, except for the very top ultra athlete acclimatized to altitude. It is somewhat higher than the peak of Mt. Everest. A normal person from sea level will pass out within a minute, a 'normal' mountain climber might last 5 minutes.

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It won't be pleasant. The main result of being exposed outside at altitude, besides the obvious hypothermia, frostbite and hypoxia, will be bruising from the 280-ish knot slipstream (it's the indicated airspeed that matters as far was what you feel, not the true airspeed), and injuries from being flung around by any turbulent flow you are in. Most of your skin that was exposed directly to the slipstream will have bruising.

When I was skydiving I tried tucking in and diving straight down instead of the normal 120 mph flat freefall position, just to see what it was like. You accelerate to about 150-160 mph. It got to be a bit uncomfortable at that speed.

A friend's dad once ejected from an F-104 while going just below transonic speed, and I got to ask him about it back in the 70s. He said he was purple from head to toe except where his face was protected by his helmet visor and oxygen mask (except for the purple mask outline bruise on his face).

Even better, you can read about this British Airways BAC One-Eleven driver, the one who got sucked halfway out the windshield when it blew out back in 1990. He had broken bones in addition to the other stuff, from being beaten against the fuselage like a rag doll the whole time. The crew were able to hang on to him because his legs were still hooked around the windshield frame, providing some mechanical advantage for the crew members trying to hold him in over the airstream trying to pull him free.

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  • $\begingroup$ He said he was purple from head to toe was that because of the cold? That got through his equipment? $\endgroup$ – WoJ Apr 5 at 9:05
  • $\begingroup$ Bruising from the slipstream on the parts of his abdomen and legs that were directly exposed to the blast, protected only by flight suit fabric and straps etc, as he went out in the ejection seat. The topic came up because he had a "Caterpillar Club" plaque on his mantle (awarded to pilots who've ejected). $\endgroup$ – John K Apr 5 at 12:48
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    $\begingroup$ @woj From ejection at transonic speed? He would have been purple from the 20-25g of deceleration resulting from slamming into solid c̶o̶n̶c̶r̶e̶t̶e̶ air at transonic speeds. (the 12-14g of the ejection seat would do him no favors either, of course) $\endgroup$ – PcMan Apr 5 at 17:11
  • $\begingroup$ Read again. I said just below transonic. In any case, pilots have ejected while supersonic and survived, although injured a lot worse businessinsider.com/… $\endgroup$ – John K Apr 5 at 17:50
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This is from Irish Luck - Surviving Partial Ejection from A-6 Aircraft. In this incident, the bombardier/navigator's ejection seat came part way out of an A-6, leaving the head and upper body exposed. (The web page includes pictures of the incident, as well as the pilot's account of the event.)

Some quotes from the bombardier/navigator's report:

Before I could complete that thought, there was a loud bang, followed by wind, noise, disorientation and more wind, wind, wind. Confusion reigned in my mind as I was forced back against my seat, head against the headrest, arms out behind me, the wind roaring in my head, pounding against my body.

Pain, confusion, panic, fear and denial surged through my brain and body as a new development occurred to me: I couldn't breathe. My helmet and mask had ripped off my head, and without them, the full force of the wind was hitting me square in the face. It was like trying to drink through a fire hose. I couldn't seem to get a breath of air amidst the wind. My arms were dragging along behind me until I managed to pull both of them into my chest and hold them there. I tried to think for a second as I continued my attempts to breathe.

The wind had become physically and emotionally overwhelming. It pounded against my face and body like a huge wall of water that wouldn't stop. The roaring in my ears confused me, the pressure in my mouth prevented me from breathing, and the pounding on my eyes kept me from seeing. Time had lost all meaning. For all I knew, I could have been sitting there for seconds or for hours. I was suffocating, and I couldn't seem to get a breath. I wish I could say that my last thoughts were of my wife, but as I felt myself blacking out, all I said was, "I don't want to die.

So definitely not pleasant.

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    $\begingroup$ Checking the article for the important bit: “We were at 8,000 feet, […] At 230 knots […]”. The indicated airspeed of a cruising airliner is not much higher, about 250 knots, so the rush of wind won't be much worse (though the turbulence will produce shorter period gusts). It is, however, still pleasantly warm at 8,000 ft, while it's freezing -54°C up at FL360. $\endgroup$ – Jan Hudec Apr 3 at 12:52
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A skydiver in free fall is fully supported (i.e. no longer accelerating, but falling at constant velocity) at about the same speed as your example motorcycle.

Wind resistance is generally proportional to the square of speed, other factors equal (same shape in the same orientation, mainly), so moving at three times the speed on the wing of an airliner would offer about 9x the force -- or, put another way, you'd have nine times your weight in wind resistance force pushing you off the wing.

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  • $\begingroup$ But the air is also thinner up there. Would that affect? $\endgroup$ – Nederealm Apr 2 at 18:28
  • $\begingroup$ So is it possible with the right equipment (oxygen and temperature control) to be tethered and secured outside the aircraft while the aircraft is in flight at it's typical ground speed and survive? $\endgroup$ – Nederealm Apr 2 at 18:31
  • $\begingroup$ Thinner air reduces the air resistance somewhat, but not enough to be a big deal. And yes, it's possible -- it is undeniably a Bad Idea to tether yourself outside an aircraft at -30C, 900 km/hr, and 10 km altitude, but with the right preparation, it ought to be possible to survive the experience. $\endgroup$ – Zeiss Ikon Apr 2 at 18:41
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    $\begingroup$ @ZeissIkon, the density ratio (local density to standard sea-level density) up at FL360 is about 0.3, which is the scaling factor for aerodynamic forces. So at 850 km/h you won't feel 18 times the force at 200 km/h sea-level, only 5.4 times. Still too much. And you are already encountering compressibility effects as it is M0.8 (speed of sound only depends on temperature and standard temperature at FL360 is -54°C (local minimum)) $\endgroup$ – Jan Hudec Apr 3 at 12:37
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    $\begingroup$ @Nederealm The air plane still has to support its own weight, and to do so in thinner air, it just compensates by flying even faster, as both lift and drag are proportional to the square of velocity. $\endgroup$ – DKNguyen Apr 3 at 23:56
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It would be incredibly painful for a minute or so, and then you’d be dead.

As others have noted, drag goes goes up with the square of speed, so three times the speed means nine times the drag.

If you used a simple belt harness, the belt would be pulled straight through your torso. The two halves of your body would then free-fall, but you’d lose consciousness from the blood loss long before they hit the ground.

If you used a smarter full-body harness, your skeleton and internal organs would be crushed to a pulp (like an elephant sitting on you), and you’d die much faster.

0/5 stars, would not recommend.

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    $\begingroup$ This is an insightful answer. But, I am wondering about the actual physics of it in reality. From personal experience, I can tell you that it is quite possible to exit an aircraft at speeds as high as 190 knots. It is also quite possible to actually spend time hanging on to the outside of an aircraft at speeds up to 150 knots with absolutely no difficulty. These are indicated airspeeds. Based on this experience, I have no doubts that a reasonably fit person could hang on to a railing on the outside of an aircraft at airspeeds over 200 knots. Probably 250 KIAS with proper protection. $\endgroup$ – Dean F. Apr 3 at 16:27
  • $\begingroup$ "...and then you’d be dead." Not necessarily. $\endgroup$ – Vikki Apr 3 at 21:39
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    $\begingroup$ Historically, various countries used being torn apart by horses pulling limbs off as a method of capital punishment. On a good day, two horses could maybe just do it, if they (and the victim) were lucky. Sometimes four horses were not enough. So I think your estimates of what's needed to cause those levels or damage are out by orders of magnitude. Even broken bones would be questionable, because there aren't the point loadings which cause breaks. $\endgroup$ – Graham Apr 3 at 22:05
  • $\begingroup$ Drag at 190 knots is nothing compared to cruising speed. i have ridden motorbikes at 325 km/h which is about 175 knots, and it blows, but it is ok. Cruising speed is more than double that! $\endgroup$ – Aganju Apr 3 at 23:30
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    $\begingroup$ @Vikki-formerlySean That incident was at around 17,300 feet, though, not cruising altitude. It would thus have not been traveling at cruise speed (though still quite fast.) $\endgroup$ – reirab Apr 4 at 5:32
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I haven't climbed out of an airplane at extremely high speeds, and would prefer not to do so. I've climbed out of many at lower speeds and altitudes (to low 20,000's), and have free-fallen.

The best description I can offer for being in freefall or in the free air slipstream outside of an airplane is that it's like floating in loud water that you can breathe.

The breathing issue is temperated by altitude, but at altitudes above which oxygen may be required, it's necessary to use supplementary oxygen for the exit and initial descent, and to go on oxygen for a period of time prior to getting out of the airplane, or prior to depressurization to make the exit.

Aside from that, it's cold in most locations, until one descends in freefall to a lower altitude.

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