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Danny Beckett
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Edit: Ok, I don't have time at the moment to run all of the numbers, but one thing did come to mind that helps in the comparison: terminal velocity. Terminal velocity is the point at which the upward drag on a falling object is equal to the downward gravitational force and, thus, downward acceleration due to gravity stops. Where this provides some insight on this question is in the comparison of forces. Terminal velocity for a human is about 120 mph at low altitude. This means that the wind speed required to equal the gravitational force is approximately 120 mph at low altitude (of course, this can vary depending on the shape and mass of the person in question and their position relative to the airflow.) Since drag is proportional to the square of velocity and linearly proportional to air density, this means that a 550 mph wind at an altitude where air density was roughly 1/3$\frac13$ of at the surface would exert a force with a magnitude of about (550 / 120)^2 * (1/3) = ~7$(\frac{550}{120})^2(\frac13)\approx7$ times the magnitude of the gravitational force. So, at least initially, you'd be accelerated backwards about 7 times as quickly as you'd be accelerated downwards by gravity in these conditions. Aside from the fact that being accelerated backwards at around 7 Gs is going to hurt, there is a very real possibility of hitting any part of the aircraft that happens to be behind you. Also, as mentioned in a comment below, it would actually be entirely possible to be accelerated upwards (at least briefly) with that much drag, depending on the average angle at which your body is deflecting the wind stream. Another consideration is that the windstream itself will be faster than the true airspeed of the aircraft itself around certain parts of the aircraft, including around the fuselage and above and behind the wings. Furthermore, the airstream is not always exactly parallel with the aircraft. It can have an upward component relative to the aircraft around certain parts of the airframe while it almost always has a downward component relative to the aircraft behind the trailing edge of the wings. Also, if the plane itself is descending, there will be an upward component of the airstream relative to the aircraft at almost all points, except maybe right behind the wings. So, long story short, a lot of factors play into this, but things aren't looking up for the prospective jumper.

Edit: Ok, I don't have time at the moment to run all of the numbers, but one thing did come to mind that helps in the comparison: terminal velocity. Terminal velocity is the point at which the upward drag on a falling object is equal to the downward gravitational force and, thus, downward acceleration due to gravity stops. Where this provides some insight on this question is in the comparison of forces. Terminal velocity for a human is about 120 mph at low altitude. This means that the wind speed required to equal the gravitational force is approximately 120 mph at low altitude (of course, this can vary depending on the shape and mass of the person in question and their position relative to the airflow.) Since drag is proportional to the square of velocity and linearly proportional to air density, this means that a 550 mph wind at an altitude where air density was roughly 1/3 of at the surface would exert a force with a magnitude of about (550 / 120)^2 * (1/3) = ~7 times the magnitude of the gravitational force. So, at least initially, you'd be accelerated backwards about 7 times as quickly as you'd be accelerated downwards by gravity in these conditions. Aside from the fact that being accelerated backwards at around 7 Gs is going to hurt, there is a very real possibility of hitting any part of the aircraft that happens to be behind you. Also, as mentioned in a comment below, it would actually be entirely possible to be accelerated upwards (at least briefly) with that much drag, depending on the average angle at which your body is deflecting the wind stream. Another consideration is that the windstream itself will be faster than the true airspeed of the aircraft itself around certain parts of the aircraft, including around the fuselage and above and behind the wings. Furthermore, the airstream is not always exactly parallel with the aircraft. It can have an upward component relative to the aircraft around certain parts of the airframe while it almost always has a downward component relative to the aircraft behind the trailing edge of the wings. Also, if the plane itself is descending, there will be an upward component of the airstream relative to the aircraft at almost all points, except maybe right behind the wings. So, long story short, a lot of factors play into this, but things aren't looking up for the prospective jumper.

I don't have time at the moment to run all of the numbers, but one thing did come to mind that helps in the comparison: terminal velocity. Terminal velocity is the point at which the upward drag on a falling object is equal to the downward gravitational force and, thus, downward acceleration due to gravity stops. Where this provides some insight on this question is in the comparison of forces. Terminal velocity for a human is about 120 mph at low altitude. This means that the wind speed required to equal the gravitational force is approximately 120 mph at low altitude (of course, this can vary depending on the shape and mass of the person in question and their position relative to the airflow.) Since drag is proportional to the square of velocity and linearly proportional to air density, this means that a 550 mph wind at an altitude where air density was roughly $\frac13$ of at the surface would exert a force with a magnitude of about $(\frac{550}{120})^2(\frac13)\approx7$ times the magnitude of the gravitational force. So, at least initially, you'd be accelerated backwards about 7 times as quickly as you'd be accelerated downwards by gravity in these conditions. Aside from the fact that being accelerated backwards at around 7 Gs is going to hurt, there is a very real possibility of hitting any part of the aircraft that happens to be behind you. Also, as mentioned in a comment below, it would actually be entirely possible to be accelerated upwards (at least briefly) with that much drag, depending on the average angle at which your body is deflecting the wind stream. Another consideration is that the windstream itself will be faster than the true airspeed of the aircraft itself around certain parts of the aircraft, including around the fuselage and above and behind the wings. Furthermore, the airstream is not always exactly parallel with the aircraft. It can have an upward component relative to the aircraft around certain parts of the airframe while it almost always has a downward component relative to the aircraft behind the trailing edge of the wings. Also, if the plane itself is descending, there will be an upward component of the airstream relative to the aircraft at almost all points, except maybe right behind the wings. So, long story short, a lot of factors play into this, but things aren't looking up for the prospective jumper.

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reirab
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Edit: Ok, I don't have time at the moment to run all of the numbers, but one thing did come to mind that helps in the comparison: terminal velocity. Terminal velocity is the point at which the upward drag on a falling object is equal to the downward gravitational force and, thus, downward acceleration due to gravity stops. Where this provides some insight on this question is in the comparison of forces. Terminal velocity for a human is about 120 mph at low altitude. This means that the wind speed required to equal the gravitational force is approximately 120 mph at low altitude (of course, this can vary depending on the shape and mass of the person in question and their position relative to the airflow.) Since drag is proportional to the square of velocity and linearly proportional to air density, this means that a 550 mph wind at an altitude where air density was roughly 1/3 of at the surface would exert a force with a magnitude of about (550 / 120)^2 * (1/3) = ~7 times the magnitude of the gravitational force. So, at least initially, you'd be accelerated backwards about 7 times as quickly as you'd be accelerated downwards by gravity in these conditions. Aside from the fact that being accelerated backwards at around 7 Gs is going to hurt, there is a very real possibility of hitting any part of the aircraft that happens to be behind you. Also, as mentioned in a comment below, it would actually be entirely possible to be accelerated upwards (at least briefly) with that much drag, depending on the average angle at which your body is deflecting the wind stream. Another consideration is that the windstream itself will be faster than the indicatedtrue airspeed of the aircraft itself around certain parts of the aircraft, including around the fuselage and above and behind the wings. Furthermore, the airstream is not always exactly parallel with the aircraft. It can have an upward component relative to the aircraft around certain parts of the airframe while it almost always has a downward component relative to the aircraft behind the trailing edge of the wings. Also, if the plane itself is descending, there will be an upward component of the airstream relative to the aircraft at almost all points, except maybe right behind the wings. So, long story short, a lot of factors play into this, but things aren't looking up for the prospective jumper.

Edit: Ok, I don't have time at the moment to run all of the numbers, but one thing did come to mind that helps in the comparison: terminal velocity. Terminal velocity is the point at which the upward drag on a falling object is equal to the downward gravitational force and, thus, downward acceleration due to gravity stops. Where this provides some insight on this question is in the comparison of forces. Terminal velocity for a human is about 120 mph at low altitude. This means that the wind speed required to equal the gravitational force is approximately 120 mph at low altitude (of course, this can vary depending on the shape and mass of the person in question and their position relative to the airflow.) Since drag is proportional to the square of velocity and linearly proportional to air density, this means that a 550 mph wind at an altitude where air density was roughly 1/3 of at the surface would exert a force with a magnitude of about (550 / 120)^2 * (1/3) = ~7 times the magnitude of the gravitational force. So, at least initially, you'd be accelerated backwards about 7 times as quickly as you'd be accelerated downwards by gravity in these conditions. Aside from the fact that being accelerated backwards at around 7 Gs is going to hurt, there is a very real possibility of hitting any part of the aircraft that happens to be behind you. Also, as mentioned in a comment below, it would actually be entirely possible to be accelerated upwards (at least briefly) with that much drag, depending on the average angle at which your body is deflecting the wind stream. Another consideration is that the windstream itself will be faster than the indicated airspeed around certain parts of the aircraft, including around the fuselage and above and behind the wings. Furthermore, the airstream is not always exactly parallel with the aircraft. It can have an upward component relative to the aircraft around certain parts of the airframe while it almost always has a downward component relative to the aircraft behind the trailing edge of the wings. Also, if the plane itself is descending, there will be an upward component of the airstream relative to the aircraft at almost all points, except maybe right behind the wings. So, long story short, a lot of factors play into this, but things aren't looking up for the prospective jumper.

Edit: Ok, I don't have time at the moment to run all of the numbers, but one thing did come to mind that helps in the comparison: terminal velocity. Terminal velocity is the point at which the upward drag on a falling object is equal to the downward gravitational force and, thus, downward acceleration due to gravity stops. Where this provides some insight on this question is in the comparison of forces. Terminal velocity for a human is about 120 mph at low altitude. This means that the wind speed required to equal the gravitational force is approximately 120 mph at low altitude (of course, this can vary depending on the shape and mass of the person in question and their position relative to the airflow.) Since drag is proportional to the square of velocity and linearly proportional to air density, this means that a 550 mph wind at an altitude where air density was roughly 1/3 of at the surface would exert a force with a magnitude of about (550 / 120)^2 * (1/3) = ~7 times the magnitude of the gravitational force. So, at least initially, you'd be accelerated backwards about 7 times as quickly as you'd be accelerated downwards by gravity in these conditions. Aside from the fact that being accelerated backwards at around 7 Gs is going to hurt, there is a very real possibility of hitting any part of the aircraft that happens to be behind you. Also, as mentioned in a comment below, it would actually be entirely possible to be accelerated upwards (at least briefly) with that much drag, depending on the average angle at which your body is deflecting the wind stream. Another consideration is that the windstream itself will be faster than the true airspeed of the aircraft itself around certain parts of the aircraft, including around the fuselage and above and behind the wings. Furthermore, the airstream is not always exactly parallel with the aircraft. It can have an upward component relative to the aircraft around certain parts of the airframe while it almost always has a downward component relative to the aircraft behind the trailing edge of the wings. Also, if the plane itself is descending, there will be an upward component of the airstream relative to the aircraft at almost all points, except maybe right behind the wings. So, long story short, a lot of factors play into this, but things aren't looking up for the prospective jumper.

Added information due to comments.
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reirab
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A further issue to consider is the locations of the exits. The reason that it was possible to bail from a 727 is that it had an exit in the tail cone. No other passenger aircraft that I'm aware of has that. Many military cargo planes (like the C-130 you mentioned) do use ramps in the tail, though, and that's where people jump out from in those aircraft. If you try to jump from a side door in a jetliner (which are the only doors that exist in most modern jetliners,) you'll likely be promptly cut in half by the horizontal stabilizers moving through you at 550 mph immediately after stepping out the door. Of course, this would also damage the horizontal stabilizer, which would then quite likely result in the death of everyone still on the plane, due to loss of pitch authority. Of course, if you jump out of a door in front of the wings, you might be killed by a wing or an engine rather than a horizontal stabilizer, but the results are still equally undesirable. Jumping out of side doors is possible (and normal) for the much slower aircraft used for skydiving, but not for a passenger jet moving 550 mph.

Edit: Ok, I don't have time at the moment to run all of the numbers, but one thing did come to mind that helps in the comparison: terminal velocity. Terminal velocity is the point at which the upward drag on a falling object is equal to the downward gravitational force and, thus, downward acceleration due to gravity stops. Where this provides some insight on this question is in the comparison of forces. Terminal velocity for a human is about 120 mph at low altitude. This means that the wind speed required to equal the gravitational force is approximately 120 mph at low altitude (of course, this can vary depending on the shape and mass of the person in question and their position relative to the airflow.) Since drag is proportional to the square of velocity and linearly proportional to air density, this means that a 550 mph wind at an altitude where air density was roughly 1/3 of at the surface would exert a force with a magnitude of about (550 / 120)^2 * (1/3) = ~7 times the magnitude of the gravitational force. So, at least initially, you'd be accelerated backwards about 7 times as quickly as you'd be accelerated downwards by gravity in these conditions. Aside from the fact that being accelerated backwards at around 7 Gs is going to hurt, there is a very real possibility of hitting any part of the aircraft that happens to be behind you. Also, as mentioned in a comment below, it would actually be entirely possible to be accelerated upwards (at least briefly) with that much drag, depending on the average angle at which your body is deflecting the wind stream. Another consideration is that the windstream itself will be faster than the indicated airspeed around certain parts of the aircraft, including around the fuselage and above and behind the wings. Furthermore, the airstream is not always exactly parallel with the aircraft. It can have an upward component relative to the aircraft around certain parts of the airframe while it almost always has a downward component relative to the aircraft behind the trailing edge of the wings. Also, if the plane itself is descending, there will be an upward component of the airstream relative to the aircraft at almost all points, except maybe right behind the wings. So, long story short, a lot of factors play into this, but things aren't looking up for the prospective jumper.

A further issue to consider is the locations of the exits. The reason that it was possible to bail from a 727 is that it had an exit in the tail cone. No other passenger aircraft that I'm aware of has that. Many military cargo planes (like the C-130 you mentioned) do use ramps in the tail, though, and that's where people jump out from in those aircraft. If you try to jump from a side door (which are the only doors that exist in most modern jetliners,) you'll likely be promptly cut in half by the horizontal stabilizers moving through you at 550 mph immediately after stepping out the door. Of course, this would also damage the horizontal stabilizer, which would then quite likely result in the death of everyone still on the plane, due to loss of pitch authority. Of course, if you jump out of a door in front of the wings, you might be killed by a wing or an engine rather than a horizontal stabilizer, but the results are still equally undesirable. Jumping out of side doors is possible (and normal) for the much slower aircraft used for skydiving, but not for a passenger jet moving 550 mph.

A further issue to consider is the locations of the exits. The reason that it was possible to bail from a 727 is that it had an exit in the tail cone. No other passenger aircraft that I'm aware of has that. Many military cargo planes (like the C-130 you mentioned) do use ramps in the tail, though, and that's where people jump out from in those aircraft. If you try to jump from a side door in a jetliner (which are the only doors that exist in most modern jetliners,) you'll likely be promptly cut in half by the horizontal stabilizers moving through you at 550 mph immediately after stepping out the door. Of course, this would also damage the horizontal stabilizer, which would then quite likely result in the death of everyone still on the plane, due to loss of pitch authority. Of course, if you jump out of a door in front of the wings, you might be killed by a wing or an engine rather than a horizontal stabilizer, but the results are still equally undesirable. Jumping out of side doors is possible (and normal) for the much slower aircraft used for skydiving, but not for a passenger jet moving 550 mph.

Edit: Ok, I don't have time at the moment to run all of the numbers, but one thing did come to mind that helps in the comparison: terminal velocity. Terminal velocity is the point at which the upward drag on a falling object is equal to the downward gravitational force and, thus, downward acceleration due to gravity stops. Where this provides some insight on this question is in the comparison of forces. Terminal velocity for a human is about 120 mph at low altitude. This means that the wind speed required to equal the gravitational force is approximately 120 mph at low altitude (of course, this can vary depending on the shape and mass of the person in question and their position relative to the airflow.) Since drag is proportional to the square of velocity and linearly proportional to air density, this means that a 550 mph wind at an altitude where air density was roughly 1/3 of at the surface would exert a force with a magnitude of about (550 / 120)^2 * (1/3) = ~7 times the magnitude of the gravitational force. So, at least initially, you'd be accelerated backwards about 7 times as quickly as you'd be accelerated downwards by gravity in these conditions. Aside from the fact that being accelerated backwards at around 7 Gs is going to hurt, there is a very real possibility of hitting any part of the aircraft that happens to be behind you. Also, as mentioned in a comment below, it would actually be entirely possible to be accelerated upwards (at least briefly) with that much drag, depending on the average angle at which your body is deflecting the wind stream. Another consideration is that the windstream itself will be faster than the indicated airspeed around certain parts of the aircraft, including around the fuselage and above and behind the wings. Furthermore, the airstream is not always exactly parallel with the aircraft. It can have an upward component relative to the aircraft around certain parts of the airframe while it almost always has a downward component relative to the aircraft behind the trailing edge of the wings. Also, if the plane itself is descending, there will be an upward component of the airstream relative to the aircraft at almost all points, except maybe right behind the wings. So, long story short, a lot of factors play into this, but things aren't looking up for the prospective jumper.

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reirab
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