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Regarding rail guns. Rail guns don't work, at least not practically, and even the US military is on the verge of totally giving up on that technology.
I am doubtful that an object with exit velocity at mach 7 can even reach 29,000 feet (height of Everest where air is too thin for human).
Since you're such an expert, perhaps you could explain why Thunderfoot is wrong, using the relevant mathematics and physics?
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Regarding rail guns. Rail guns don't work, at least not practically, and even the US military is on the verge of totally giving up on that technology.
Rail gun has a demonstrated velocity of around mach 7 by the US Navy. Mach 7 is around 2.3km/s and is around Spinlauch's planned launch speed. So while rail gun may not be suitable to be carried around by ships yet, it is certainly feasible for a fix-located rail gun to get to mach 7 exit velocity.
I am doubtful that an object with exit velocity at mach 7 can even reach 29,000 feet (height of Everest where air is too thin for human).
Garden-variety artillery with muzzle velocities under Mach 3 can reach over 50,000 feet altitude.
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You have probably missed the news. https://www.thedefensepost.com/2021/07/08/us-navy-railgun/
Basically, huge money sink that never started to work reliably.
Which set of axioms state that one cannot possibly solve those issues?
Which set of axioms state that one cannot possibly solve those issues?
https://de.wikipedia.org/wiki/Str%C3%B6mungswiderstand
Note the v square, which is a pretty effective way to not be able to easily reach escape speed plus creating enormous heat (turning the drag into heat, which will probably melt wolfram and ceramics).
The slingshot method requires having escape speed plus losses due to drag at start in the densest medium. I assume a nice fireball, when then projectile vaporizes on exit, hitting air.
A rocket will slowly (in comparison) reach the escape speed - and that's in the least dense medium (downside: it has to carry its fuel).
Which set of axioms state that one cannot possibly solve those issues?
https://de.wikipedia.org/wiki/Str%C3%B6mungswiderstand
Note the v square, which is a pretty effective way to not be able to easily reach escape speed plus creating enormous heat (turning the drag into heat, which will probably melt wolfram and ceramics).
The slingshot method requires having escape speed plus losses due to drag at start in the densest medium. I assume a nice fireball, when then projectile vaporizes on exit, hitting air.
A rocket will slowly (in comparison) reach the escape speed - and that's in the least dense medium (downside: it has to carry its fuel).
Plus they cannot afford to put heavy heat shielding on a small launch vehicle that is supposed to be mostly payload.
perhaps you could explain why Thunderfoot is wrong
Spinlaunch is proposing a 100 meter spinning diameter, so we use 100 meter rail gun as base comparison.
A much longer rail gun will reduce acceleration G force as well as decrease the power needed for acceleration.
I assume a nice fireball, when then projectile vaporizes on exit, hitting air.
A rocket will slowly (in comparison) reach the escape speed - and that's in the least dense medium (downside: it has to carry its fuel).
What would the centripetal g force on the payload be compared with simply shooting it out of a very large gun pointed skyward?
Since you're such an expert, perhaps you could explain why Thunderfoot is wrong, using the relevant mathematics and physics?He is not wrong with his calculations, it's just that the publicly available data he used isn't enough for any meaningful analysis. Yes there is high acceleration on the launch vehicle by principle and they appeared to have stability problems on their very first test. Which set of axioms state that one cannot possibly solve those issues?
It would be interesting to know if it's possible to fire a rocket from a gun barrel and then have it ignite when it reached apogee.
It would be interesting to know if it's possible to fire a rocket from a gun barrel and then have it ignite when it reached apogee.There are artillery rounds that do this, although they fire earlier since they are only after the increased range. I don't see why you couldn't extend the principle, with less shell and more rocket.
The forces on the bearings of this centrifuge will also be quite interesting. Has anyone calculated how carefully one needs to balance the whole thing to keep the vibrations in check?
I assume a nice fireball, when then projectile vaporizes on exit, hitting air.
A rocket will slowly (in comparison) reach the escape speed - and that's in the least dense medium (downside: it has to carry its fuel).
It will get hot and perhaps require an ablative shield, but will be out of the lower atmosphere in seconds. Sprint ABM missiles exceeded Mach 10 in the lower-to-mid atmospheric ranges where they operated. I'm sure they got hot.
Since you're such an expert, perhaps you could explain why Thunderfoot is wrong, using the relevant mathematics and physics?He is not wrong with his calculations, it's just that the publicly available data he used isn't enough for any meaningful analysis. Yes there is high acceleration on the launch vehicle by principle and they appeared to have stability problems on their very first test. Which set of axioms state that one cannot possibly solve those issues? Satellites that survive such high-g launchers are not an entirely new thing and have already been studied.
What else was there? I don't think Saddam Hussein competing on the space launcher market will be a reasonable concern anytime soon. And liquid-propellant engines that can ignite in microgravity are used on satellites all the time.
Just see Thunderfoot vs. Space X. Uniquely the only scam company in the world to successfully operate a manned space program....
Regarding rail guns. Rail guns don't work, at least not practically, and even the US military is on the verge of totally giving up on that technology.
Rail gun has a demonstrated velocity of around mach 7 by the US Navy. Mach 7 is around 2.3km/s and is around Spinlauch's planned launch speed. So while rail gun may not be suitable to be carried around by ships yet, it is certainly feasible for a fix-located rail gun to get to mach 7 exit velocity.
You have probably missed the news. https://www.thedefensepost.com/2021/07/08/us-navy-railgun/
Basically, huge money sink that never started to work reliably.
The forces on the bearings of this centrifuge will also be quite interesting. Has anyone calculated how carefully one needs to balance the whole thing to keep the vibrations in check?
No. This is basically an academic question as the whole thing isn't going to work anyway.
But given the centripetal acceleration of the setup with the disclosed numbers as around 11000 x g, insert whatever payload mass you find reasonable ( ) into F = m * a and you have the effective forces.
Seems to me the biggest problem is letting go of the payload, not because it will burn up but because of the sudden unbalancing of the spinner. The video Dave posted illustrates the issue pretty well - in most of the windmill destructions I've seen, one arm lets go and the shock of that breaks the other two arms which then let go in sympathy.
But... what if that doesn't matter? When they used to launch rockets I bet no-one ever said "No, this will never work because the first stage won't survive coming down." Losing most of the rocket is just the cost of doing business (or used to be). So what if the destruction of the wheel is just the cost of this style of launching?
Against that, it would be a pretty spectacular loss of functionality...
We can discuss Spinlaunch to no end, but I'm personally pretty sure it will never go anywhere while having eaten a ton of cash. Where's the popcorn?
We can discuss Spinlaunch to no end, but I'm personally pretty sure it will never go anywhere while having eaten a ton of cash. Where's the popcorn?