Timeline for Why don't we use catapults to get to space?
Current License: CC BY-SA 3.0
17 events
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| Jan 15, 2018 at 22:39 | comment | added | brichins | While this is broadly correct, the line about humans "becoming a wet spot after 10 g's" is catchy but definitely wrong. It would probably black out the pilot and passengers (definitely A Bad Thing), but it's almost impossible to 'squish' a human into a puddle with acceleration alone. The wikipedia article on g-force has some quick reading on human limits, which depend heavily on orientation and duration. 10 g won't necessarily even black you out in short durations - the human record in formal testing is 46.2 g on a rocket sled. | |
| Dec 21, 2017 at 16:11 | comment | added | Anthony X | The aircraft launch catapult on an aircraft carrier only accelerates an aircraft to about 140 knots or so, far less than even mach 0.5 - see en.wikipedia.org/wiki/Aircraft_catapult | |
| Apr 13, 2017 at 12:58 | history | edited | CommunityBot |
replaced http://space.stackexchange.com/ with https://space.stackexchange.com/
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| Apr 13, 2017 at 12:43 | history | edited | CommunityBot |
replaced http://scifi.stackexchange.com/ with https://scifi.stackexchange.com/
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| Dec 12, 2016 at 21:55 | comment | added | Joshua | @BenCrowell: Answer assumes carrying fuel, for which the exponential term of accelerating your fuel dominates for chemical fuels to orbit. | |
| Sep 1, 2016 at 2:33 | comment | added | user687 | Work to accelerate grows exponentially with target speed and object mass Not true. It grows quadratically with speed and linearly with mass. Neither dependence is exponential. | |
| May 26, 2016 at 11:10 | comment | added | sampathsris | About the point about atmosphere being thick closest to the ground. We can have a look at drag equation. Trying to go at high velocities through a thick fluid is wasting fuel. | |
| Oct 2, 2014 at 7:24 | history | edited | user | CC BY-SA 3.0 |
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| Sep 30, 2014 at 10:36 | comment | added | user | @Falco I believe I largely addressed that with my third paragraph; the one that starts with "The weight of an aircraft". Also possibly the third-from-bottom paragraph; "The atmosphere is thickest closest to ground". | |
| Sep 30, 2014 at 9:45 | comment | added | Falco | Most of these points address the problems with an actual catapult trying to throw something up into orbit. But like the F-18 starts its Engines while still on deck, the rocket on the catapult could also start its engine before liftoff. Imagine the Starting-POD was a giant elevator going really fast upwards, while the rockets starts its engines. Wouldn't the rocket get additional energy from the elevator/catapult and thus need less fuel? | |
| Sep 29, 2014 at 10:54 | history | edited | user | CC BY-SA 3.0 |
Stupid typo
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| Sep 29, 2014 at 10:40 | vote | accept | Pavel Janicek | ||
| Sep 29, 2014 at 10:40 | comment | added | Pavel Janicek | Terrible idea connected with laziness to do the math :) Ever happened to you that you had an idea knowing that such idea is bad, but because you are so deep in the idea itself, you cannot see why? :) Thanks a lot for thoughtful answer. | |
| Sep 29, 2014 at 9:48 | history | edited | user | CC BY-SA 3.0 |
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| Sep 29, 2014 at 8:30 | history | edited | user | CC BY-SA 3.0 |
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| Sep 29, 2014 at 8:25 | history | edited | user | CC BY-SA 3.0 |
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| Sep 29, 2014 at 8:14 | history | answered | user | CC BY-SA 3.0 |