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Jump from a plane about to crash


aLeXmOrA

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... Last time I checked, being able to make 40g half second jump has no restraints like a nice F1 car would.

Also would you like to ask all those people that die from all those sub-20g decelerations into things?

Oh

... Oh. Right, something about 100g for 100ms guys surviving being this whole... Random event thing. Right, lots of other people die from sudden stops too. I guess this whoe survival thing is relative right? 0.1% is way, way better than 0%.

I assume modern motor gliders are nonexistent in your world then, carry on in the AN-2 there then.

...Unless you\'re just a flight sim guy... Because easier to stall does relate to 'how' it will stall... Or how you will enter the Flanker Inverted Flatspin Death Spiralâ„¢. Righto, something about gliders having nice stalling characteristics instead of 'you\'re dead' when your nose decides to yaw into the ground.

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... Last time I checked, being able to make 40g half second jump has no restraints like a nice F1 car would.

I never suggested it did. Re-read my posts. I AGREE WITH YOU - MAKING A SURVIVABLE JUMP IS IMPOSSIBLE.

But surviving a 40g crash, presuming you were buckled in with the tray table up, etc. etc. is very likely.

Also would you like to ask all those people that die from all those sub-20g decelerations into things?

People don\'t die from sub-20g instantaneous accelerations. Col. Stapp proved that.

So I guess the only thing I would ask those people is, 'why didn\'t you wear your seatbelt?'

... Oh. Right, something about 100g for 100ms guys surviving being this whole... Random event thing. Right, lots of other people die from sudden stops too. I guess this whoe survival thing is relative right? 0.1% is way, way better than 0%.

Only your chances of surviving a 40g crash ARE MUCH BETTER THAN 50%.

In a F-1 car, with all the safety restraints it includes, even 100g crashes result in nearly 50% survival rates, though you will almost certainly be seriously injured.

I assume modern motor gliders are nonexistent in your world then, carry on in the AN-2 there then.

Tell you what, YOU go find a \'modern motor glider\' that stalls at less than 30 mph/26 knots and get back to us on that. ;)

...Unless you\'re just a flight sim guy... Because easier to stall does relate to 'how' it will stall... Or how you will enter the Flanker Inverted Flatspin Death Spiralâ„¢. Righto, something about gliders having nice stalling characteristics instead of 'you\'re dead' when your nose decides to yaw into the ground.

The AN-2 was DESIGNED to have benign stall characteristics, using a ridiculously low wing loading and massive leading-edge slats. Hence the incredible ability to 'parachute' to the ground in deep stall as I mentioned in the first place.... ::)

(And I\'m not 'just a flight sim guy.')

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Something to chew on:

During the battle of Petsamo in 1939, Soviet paratroopers dropped into battle. Many of these had lost parachutes, and were therefore looking for snow drifts.

Contrary to myth, this was NEVER the recommended doctrine for paratroopers even in the Soviet Union! But it is true that some of these hardcore dudes did indeed fight AFTER dropping with no parachute.

It is possible to survive. It\'s not a great idea though. :)

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Can\'t we just agree that jumping out of plane without a chute is about as stupid as arguing about metric vs imperial system, or having a 'Last person to post is the winner' thread?

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Tell you what, YOU go find a \'modern motor glider\' that stalls at less than 30 mph/26 knots and get back to us on that. ;)

The AN-2 was DESIGNED to have benign stall characteristics, using a ridiculously low wing loading and massive leading-edge slats. Hence the incredible ability to 'parachute' to the ground in deep stall as I mentioned in the first place.... ::)

Quick look-up (I know this wasn\'t aimed at me), DG-808C glider stall speed (no ballast): 35 kts.

Dr. Evo seems pretty justified mentioning that plane.

As an extra, since once parachuting your wing area is key, the DG-808 has 11.8 m^2. How much does the An-2 have? 71.52 m^2.

With lower final speed and those wings, I don\'t think it\'s hard to figure out which could parachute best.

To be clear, you said modern, and that thing is 1993. To be balanced, the SGS 2-32 (a 1962 glider) has a comparable, perhaps slightly slower stall speed, and a wing area of 16.72 m^2. Better, though still not outstanding by comparison. Saying modern probably damages your cause, tbh, as with modern gliders efficiency would be favoured against low-speed performance/safety margins: the DG-808 gets a glide ratio of 50*, or 51.5 with winglets, the SGS 2-32, a ratio of 35. With good design, you can make it fly faster, and very often better, so why would you bother with something that can fly slow?

*These figures are for the DG-808C motor variant. The unpowered variant will have less drag and thus a marginally better glide ratio, far more so with the lower weight. Before you point it out, no, the weight reduction would not be enough to account for a difference in stall speed. While it does cut it from 340 kg to 270, the minimum speed quoted is in fact still 35 kts. It wouldn\'t be enough to bring it under 30 regardless.

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I honestly have to believe there is some serious detachment from reality going on here.

Wing area does not determine stall characteristics. If that were the case I would friggin fly an A380 next to the AN-2 and then mock it and flip it over with my giant vortices. If you stall in an airliner, you will drop like a bloody brick. The AN-2 is no featherweight (Its easily several Storches for crying out loud.)

Additionally nobody brings up durations of the highest G impulse. 100g for a hundred or so miliseconds with a taper in and taper off is completely different from a mesa like '40g absolute for 500ms.' There are huge differences in energy imparted PER MILISECOND here

I\'m not going to even bother, this has turned into 'look at my one number, you\'re wrong! you\'re so wrong!' from what was an obviously 'ha, like any human could somehow push theirselves hard enough to accelerate to Mach .6... Without dying... In a half second' (Let alone the problems of windblast or anything going on here.)

This topic has turned into Minecraft levels of horribad.

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I never said wing area had anything to do with stall characteristics.

A flat board has the same coefficient of drag pretty much regardless of shape.

Perpendicular to airflow, a wing is, pretty much, a flat board.

When parachuting, as you are travelling downwards, you want as much drag as you can; lift no longer helps, since that would push you forward or back.

Thus, by d is proportional to Cd*A, for a larger wing, you will parachute better.

And no-one is bringing up the highest G impulse because -it doesn\'t matter as much as you think-. 100G for a hundred miliseconds means 100 m/s difference; enough of a change in speed that its effect is basically the same as 10G for a second. Your body can cushion out the same amount in both cases. For instance, it\'s equivalent to 10,000G for 1 millisecond: onoes over 10k geeeeez?!?!?! No, doesn\'t matter, because it was such a quick event.

For reference, there have been cases of surviving supersonic ejection, even at low altitude (1 km or so). In this instance, the pilot took two seconds between 3,000 ft and 1,000ft. That, roughly, makes an -average- of 8Gs. Gonna be much, much higher at the initial points and during the parachute deploying, which opened fully at 1,000ft. Pretty much equivalent to your example, if becoming more sustained an less instantaneous at 2 seconds. Much higher total delta-v too. The pilot (who was the one to fire the ejection, and thus was prepared) survived, though the unprepared second crew died on ejection; most likely due to the sudden wind blast managing to break his neck or such. Point is, some pretty intense forces are quite survivable in the right circumstances, most notably actually being prepared for them and bracing vulnerabilities such as the neck.

Quick edit: an extra point on the wing-parachuting-planes, is that sail planes have very little landing gear to absorb a shock, where the An-2 stood quite high by comparison, and due to its short length would be able to make quite a flare even at low altitudes, without a tailscrape.

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Like I said, detachment from reality.

That post more or less threw a bunch of numbers disconnected from 'a man jumps from a plane with enough force to from his perspective, go from 0 to Mach 0.6. Somehow his legs were able to do that and/or in the process not shear his muscles off his bones. Ignoring that problem, he somehow undergoes acceleration without ANY restraints flailing into the air at those speeds. Then he falls and most likely dies.' Right, lets ignore everything inbetween that is very wrong then bring up Wikipedia Derrived Numbers or other Web Resources to 'legitimize' random occurrence of survival in completely different scenarios (Involving seats and RESTRAINTS no less!)

This topic is not even worth it, I can no longer derrive any fun when the environment becomes something like what Minecraft players would do: 'BUT YOUR COBBLESTONE FACTORY IS INFERIOR, THESE NUMBERS PROVE YOU WRONG EVEN IF THEY ARE COMPLETELY DISPROVEN IN PRACTICE! OBVIOUSLY THIS PROVES MY MANUALLY ACTUATED REDSTONE PISTON METHOD HAS AN EFFICIENCY FACTOR OF 5.'

Numbers numbers numbers, ignoring everything about how 'uh, I doubt you can even do that in the first place, but somehow if you did without horribly maiming yourself.'

And I\'m out, I\'m not going to bother when all my former points are ignored. (Like these ever important stall characteristics of a glider versus the AN-2 and how the glider will be extremely forgiving because they are designed for that flight regime.)

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Quick look-up (I know this wasn\'t aimed at me), DG-808C glider stall speed (no ballast): 35 kts.

Dr. Evo seems pretty justified mentioning that plane.

As an extra, since once parachuting your wing area is key, the DG-808 has 11.8 m^2. How much does the An-2 have? 71.52 m^2.

With lower final speed and those wings, I don\'t think it\'s hard to figure out which could parachute best.

To be clear, you said modern, and that thing is 1993. To be balanced, the SGS 2-32 (a 1962 glider) has a comparable, perhaps slightly slower stall speed, and a wing area of 16.72 m^2. Better, though still not outstanding by comparison. Saying modern probably damages your cause, tbh, as with modern gliders efficiency would be favoured against low-speed performance/safety margins: the DG-808 gets a glide ratio of 50*, or 51.5 with winglets, the SGS 2-32, a ratio of 35. With good design, you can make it fly faster, and very often better, so why would you bother with something that can fly slow?

*These figures are for the DG-808C motor variant. The unpowered variant will have less drag and thus a marginally better glide ratio, far more so with the lower weight. Before you point it out, no, the weight reduction would not be enough to account for a difference in stall speed. While it does cut it from 340 kg to 270, the minimum speed quoted is in fact still 35 kts. It wouldn\'t be enough to bring it under 30 regardless.

Wing loading is really more important than wing area the AN-2 has an (Empty)wing loading of 46.1 kg per square meter since it weighs about 10 times what the glider does. The SGS you mentioned using your weights has a wing loading of 20.3 kg/m^2

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Dr. Evo seems pretty justified mentioning that plane.

Frankly, I\'m sorry I ever did. It was only a SIDE NOTE, and only related tangentially to the 'stalling out' concept that people were discussing. Other than that, it isn\'t really related to the topic. Though, I suppose you\'d have a better chance surviving jumping out of a slow&low-flying AN-2 than most other aircraft... though you\'d STILL have a FAR better chance of surviving if you stayed in your seat.

To be clear, you said modern, and that thing is 1993. To be balanced, the SGS 2-32 (a 1962 glider) has a comparable, perhaps slightly slower stall speed, and a wing area of 16.72 m^2. Better, though still not outstanding by comparison.

The 2-32 is not a motor glider. All motorized derivatives of it stall at MUCH higher speeds (50-70 MPH) owing to the additional weight. As a general rule, an engine adds at least as much weight to a glider as a passenger does, and with it comes a shift in certain v-speeds (stall speeds, best glide speed, minimum sink, basically anything that occurs at a fixed AOA will happen at a different speed).

Saying modern probably damages your cause, tbh, as with modern gliders efficiency would be favoured against low-speed performance/safety margins.

Very true. The 2-33 is the slowest glider I\'ve ever flown. Newer aircraft are usually faster on both ends of the spectrum.

*These figures are for the DG-808C motor variant. The unpowered variant will have less drag and thus a marginally better glide ratio, far more so with the lower weight.

Weight does not affect glide ratio. It DOES, however, affect the SPEED at which you will achieve best glide.

Before you point it out, no, the weight reduction would not be enough to account for a difference in stall speed. While it does cut it from 340 kg to 270, the minimum speed quoted is in fact still 35 kts. It wouldn\'t be enough to bring it under 30 regardless.

That\'s peculiar. It SHOULD cause an 11% drop in stall speed. Then again, most airplanes only use one 'quoted' (rather, 'marked') stall speed, measured at gross weight, despite the fact that normal stall speed is often as much as 20% less than this.

Wing area does not determine stall characteristics.

It does, but not by itself. Wing loading is more scalable, though on top of that the AN-2 also has a very high Clmax going for it as well owing to its slats.

I\'m not going to even bother, this has turned into 'look at my one number, you\'re wrong! you\'re so wrong!' from what was an obviously 'ha, like any human could somehow push theirselves hard enough to accelerate to Mach .6... Without dying... In a half second' (Let alone the problems of windblast or anything going on here.)

You\'re STILL on about that? How do you not realize that NOBODY DISAGREES WITH YOU ON THIS?! You\'re literally trying to argue a point to which there is NO opposition. Nobody is trying to suggest that it\'s possible to make such a leap. Nobody is trying to argue that jumping out of an airplane is more survivable than staying in your seat. So can we stop bringing it up?

(And, once again, mach 0.6 is an unrealistic number for low-altitude flight. 200 knots/M0.3 is much more realistic for a jet, or M0.15 for a \'typical\' piston aircraft).

And no-one is bringing up the highest G impulse because -it doesn\'t matter as much as you think-. 100G for a hundred miliseconds means 100 m/s difference; enough of a change in speed that its effect is basically the same as 10G for a second. Your body can cushion out the same amount in both cases. For instance, it\'s equivalent to 10,000G for 1 millisecond: onoes over 10k geeeeez?!?!?! No, doesn\'t matter, because it was such a quick event.

I\'m not sure that\'s completely cogent... I think 10,000G for 1 millisecond would be likened to being hit by a train moving at 200 MPH. Even for instantaneous events, some level of cushioning is preferable (crumple zones and whatnot).

Numbers numbers numbers, ignoring everything about how 'uh, I doubt you can even do that in the first place, but somehow if you did without horribly maiming yourself.'

Frankly, the only issue where that is even remotely relevant isn\'t being argued by anyone but you. Do you have an imaginary nemesis that keeps countering the claim that jumping from a plane with 200 m/s of delta-V isn\'t possible? Because none of us are, yet you keep bringing it up - as the very center of your argument, no less. The only parts we\'re correcting you on are the areas where you actually ARE wrong - the idea that 500ms accelerations are not effectively instantaneous, the idea that the AN-2 is somehow not a good (and safe) airplane for slow flight, the notion that airplanes usually fly at mach 0.6 close to the ground... all blatantly wrong. (Yet you still stand by them in the face of quantitative facts proving the opposite... ???)

But when it comes to the very answer to the question of this thread,

WE

ALL

AGREE

WITH

YOU.

How do you not understand this?

these ever important stall characteristics of a glider versus the AN-2 and how the glider will be extremely forgiving because they are designed for that flight regime.

But gliders AREN\'T designed for that flight regime! They AREN\'T designed with STOL in mind!! They\'re designed to GLIDE. Their relatively low stall speeds are merely an artifact of being built to achieve low minimum-sink rates.

The AN-2, on the other hand, was designed with STOL in mind (much like the Storch you mentioned earlier), employing tremendous wing area, leading-edge slats, large control surfaces, an upright windshield with excellent visibility... IT IS BUILT TO GO SLOW, and it DOES GO SLOW. Yet you keep irrationally claiming it is not good for this.

I get the feeling you just hate the AN-2 because it\'s ugly.

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