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Circular Runways [video]

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Re: Circular Runways [video]

#11

Post by mrfusion »

nthcolumn wrote: post #8

Okay only slightly related, I had an idea a long while ago for putting satellites into orbit where you just fling them? I didn't think it good for humans because of the G but for stuff. The win being that the power required is all on earth and you don't have to carry fuel with the payload. You could spin them up on a centrifuge and then let go at just the right time (and angle). I was going to mention it to Elon one…

You know I've been researching the very same idea. And guess what none of the math I've tried so far rules it out!

You do need a very big cable though. Think miles.

There are actually many promising technologies to get mass into space with much lower marginal cost. I think the problem is that they all have high capital costs and no one wants to take the risk on a new technology.

Re: Circular Runways [video]

#14

Post by ChuckMcM »

nthcolumn wrote: post #8

Okay only slightly related, I had an idea a long while ago for putting satellites into orbit where you just fling them? I didn't think it good for humans because of the G but for stuff. The win being that the power required is all on earth and you don't have to carry fuel with the payload. You could spin them up on a centrifuge and then let go at just the right time (and angle). I was going to mention it to Elon one…

that works well on the moon because there isn't an atmosphere to speak of but on the earth trying to accellerate to 26km/hr at sea level is both very energy intensive, and the vehicle experiences intense heating due to the atmosphere. Atmospheric drag makes this idea impractical for pretty much anything.

Re: Circular Runways [video]

#15

Post by avian »

nthcolumn wrote: post #8

Okay only slightly related, I had an idea a long while ago for putting satellites into orbit where you just fling them? I didn't think it good for humans because of the G but for stuff. The win being that the power required is all on earth and you don't have to carry fuel with the payload. You could spin them up on a centrifuge and then let go at just the right time (and angle). I was going to mention it to Elon one…

You still need to carry some fuel to achieve an orbit that does not intersect with the launch site. It's quite an old idea.

https://en.wikipedia.org/wiki/Space_gun

Re: Circular Runways [video]

#16

Post by dingaling »

saycheese wrote: post #2

Appears to be an idea that's been around before [1] - might be interesting to build a smaller scale one that's explicitly for drone swarms. [1] http://paleofuture.gizmodo.com/these-circular-runways-were-d...

Re: drones, Flight Refueling in the UK had a target-practice UAV called Falconet in the 1980s that launched from a circular runway.

It rested on a dolly secured by a cable to the central post and whirled around until take-off.

I think a couple of installations were built but most customers chose a more conventional rocket-boosted dolly for straight runways.

Re: Circular Runways [video]

#17

Post by tdb7893 »

mrfusion wrote: post #11
nthcolumn wrote: post #8

Okay only slightly related, I had an idea a long while ago for putting satellites into orbit where you just fling them? I didn't think it good for humans because of the G but for stuff. The win being that the power required is all on earth and you don't have to carry fuel with the payload. You could spin them up on a centrifuge and then let go at just the right time (and angle). I was going to mention it to Elon one…

You know I've been researching the very same idea. And guess what none of the math I've tried so far rules it out! You do need a very big cable though. Think miles. There are actually many promising technologies to get mass into space with much lower marginal cost. I think the problem is that they all have high capital costs and no one wants to take the risk on a new technology.

Wouldn't the problem be air resistance? I thought you generally need to bring fuel with you because if you don't the air will brake you too much

Re: Circular Runways [video]

#18

Post by mrfusion »

tdb7893 wrote: post #17
mrfusion wrote: post #11

Earlier quoted context omitted.

You know I've been researching the very same idea. And guess what none of the math I've tried so far rules it out! You do need a very big cable though. Think miles. There are actually many promising technologies to get mass into space with much lower marginal cost. I think the problem is that they all have high capital costs and no one wants to take the risk on a new technology.

Wouldn't the problem be air resistance? I thought you generally need to bring fuel with you because if you don't the air will brake you too much

Air resistance hurts you for sure. but the prospect of not bringing your fuel with you (see the rocket equation) really saves the most.

In my design I have the ship tethered by a cable and a pipe that's delivering the fuel.

Re: Circular Runways [video]

#20

Post by nkoren »

Nrsolis wrote: post #4

Yeah. Not so much. http://www.airliners.net/forum/viewtopic.php?t=1357935#p1941...

A lot of idiots on that forum. "Hey, in just two minutes of casual thinking about this, I've identified a flaw which a professional working on this for years has been unable to see!"

Um, yeah, not so much. The concept may have problems, but that's not how it'll be debunked.

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