#### Carmelpoet

• 2
##### Escape Velocity
« on: June 14, 2018, 03:55:14 PM »
Greetings,
If the escape velocity is 25,020 mph; how can anyone reach that speed without blacking out or being injured?  These are the numbers I found on various websites, including nasa. 25,020 mph = 11,184.941 m/s2 = 1140 g-units.  â€śModern pilots can typically handle a sustained 9g (88 m/s2)".  I understand certain variables exist that are not included in these simple equations.  But the numbers are so far apart it seems impossible.  Can someone give me some insight please?

#### Tumeni

• 1085
##### Re: Escape Velocity
« Reply #1 on: June 14, 2018, 04:14:34 PM »
Tell us what you think would cause (1) blackout, or (2) injury.

I don't see how you've gone from a static speed of 25020 mph to an acceleration of 11,184.91 metres per second squared.

The G-force calculator at https://rechneronline.de/g-acceleration/ tells us that going from 0 to 25020mph in one hour yields 0.71G. If the craft takes off from the ground, and reaches escape velocity in, say 20 minutes, even that only yields just over 2G on average.

The ISS goes around at 17k mph. If we assume a craft to have reached this orbital speed, and that it then wants to leave Earth orbit at 25k, and it does this in (say) five minutes, then it would be subject to just under 3G.
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#### Carmelpoet

• 2
##### Re: Escape Velocity
« Reply #2 on: June 14, 2018, 04:30:44 PM »
That's what was missing from the basic converters I found online, time.  Thank you for the link.

#### DuniyaGolHai

• 61
##### Re: Escape Velocity
« Reply #3 on: June 15, 2018, 05:56:02 AM »
Tell us what you think would cause (1) blackout, or (2) injury.

I don't see how you've gone from a static speed of 25020 mph to an acceleration of 11,184.91 metres per second squared.

The G-force calculator at https://rechneronline.de/g-acceleration/ tells us that going from 0 to 25020mph in one hour yields 0.71G. If the craft takes off from the ground, and reaches escape velocity in, say 20 minutes, even that only yields just over 2G on average.

The ISS goes around at 17k mph. If we assume a craft to have reached this orbital speed, and that it then wants to leave Earth orbit at 25k, and it does this in (say) five minutes, then it would be subject to just under 3G.

Just to add to this...on another perspective.

If we go by FE'ers, then everyone on earth would have blacked out very long back. (Universal acceleration)

#### junker

• Planar Moderator
• 8489
• Boom
##### Re: Escape Velocity
« Reply #4 on: June 15, 2018, 05:16:08 PM »

Just to add to this...on another perspective.

If we go by FE'ers, then everyone on earth would have blacked out very long back. (Universal acceleration)

This is simply incorrect. Even your RE friends will tell you that.

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#### Round Eyes

• 457
##### Re: Escape Velocity
« Reply #5 on: June 18, 2018, 01:24:27 AM »
Tell us what you think would cause (1) blackout, or (2) injury.

I don't see how you've gone from a static speed of 25020 mph to an acceleration of 11,184.91 metres per second squared.

The G-force calculator at https://rechneronline.de/g-acceleration/ tells us that going from 0 to 25020mph in one hour yields 0.71G. If the craft takes off from the ground, and reaches escape velocity in, say 20 minutes, even that only yields just over 2G on average.

The ISS goes around at 17k mph. If we assume a craft to have reached this orbital speed, and that it then wants to leave Earth orbit at 25k, and it does this in (say) five minutes, then it would be subject to just under 3G.

Just to add to this...on another perspective.

If we go by FE'ers, then everyone on earth would have blacked out very long back. (Universal acceleration)

Huh? 1g from acceleration and 1g from gravity is completely indistinguishable.
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