Catapult to Orbit - SpinLaunch

[Spacescifi]

3 hours ago, K^2 said:

You have a point, but solving fundamental physics problems tends to be an even less common occurrence than solving seemingly impossible business/process problems. Last instance which surpasses the challenges of spin launch is work by a certain patent clerk a century ago. Yeah, I'm that incredulous about the "engineering" challenges here.

We do have a proven method for doing this with chemical propulsion linear acceleration (aka canon), though. With just the pipe of the same length as the spin launch facility diameter, you can have a lower average acceleration over just seconds to get to the same velocity. And you don't have to de-spin the rocket after firing it out of a canon. Plus, even if you have to evacuate the chamber, which might not even be necessary, it's a much smaller volume, so you'd be able to do several launches an hour instead of (maybe) one per day with spin launch.

 

https://ancientsolarsystem.blogspot.com/2016/10/answers-for-authors-why-dont-giant-guns.html?m=1

Poor Gerard... if he were not assasinated Iraq could have had it's own space program... or long range suborbital cannon or missile launcher.

Originally Gerard wanted Canada to have it's own space program via HARP, but that is not how matters worked out.

 

Put Gerad, Zubrin, Elon, and Einstein in a room and who knows what they would come up with.... something awesome no?

Cannon launched NSWR FTW!

Edited November 30, 2021 by Spacescifi

[K^2]

17 minutes ago, Spacescifi said:

Put Gerad, Zubrin, Elon, and Einstein in a room and who knows what they would come up with.... something awesome no?

If they got along and worked together, which requires the greatest stretch of imagination so far.

[Spacescifi]

25 minutes ago, K^2 said:

If they got along and worked together, which requires the greatest stretch of imagination so far.

 

Sad but true....

[Nuke]

14 hours ago, K^2 said:

It's running at a tiny fraction of what you need for ballistic launch. This doesn't scale at all. A cannon launch is cheaper and way more practical in absolutely every single way, including requiring a lower acceleration for a much shorter duration, and we're not even doing these. I'm absolutely flabbergasted that this farce has been going on for this long. I can't imagine any remotely competent engineer signing off on this as anything beyond, "marginally plausible at a stretch." This simply has got to be a scam.

let me re-iterate i meant that i was impressed that their thing worked at all and didn't fly apart into a million pieces. i still don't think its a great way to get into space. its not scalable and you cant use it for manned launch.

i still like the idea that if you can loft a rocket to the point where a vacuum nozzle gives you better performance than a sea level nozzle you can do away with the first stage. i really dont think of this as an ssto, because the first stage is the thing on the ground, but i can imagine better ways to do this. guns are a good example. a 45 degree bore through a mountain, evacuate the tube, put a rocket on a sled in the tube and launch via gas or compressed air. perhaps a nuclear warhead detonated under ground using water as the propulsion medium.  you come out in thinned air. then your second stage lights off when you clear the mountain. 

[Spacescifi]

39 minutes ago, Nuke said:

let me re-iterate i meant that i was impressed that their thing worked at all and didn't fly apart into a million pieces. i still don't think its a great way to get into space. its not scalable and you cant use it for manned launch.

i still like the idea that if you can loft a rocket to the point where a vacuum nozzle gives you better performance than a sea level nozzle you can do away with the first stage. i really dont think of this as an ssto, because the first stage is the thing on the ground, but i can imagine better ways to do this. guns are a good example. a 45 degree bore through a mountain, evacuate the tube, put a rocket on a sled in the tube and launch via gas or compressed air. perhaps a nuclear warhead detonated under ground using water as the propulsion medium.  you come out in thinned air. then your second stage lights off when you clear the mountain. 

 

Now I wanna see orion pusher plate spaceships shot out of a cannon on a mountain!

In KSP..  since that is safer?

Are space suborbital cannons and spin launch a thing in KSP?

Should be if not.

 

Someone probably will shoot stuff directly into orbit LOL

[Nuke]

36 minutes ago, Spacescifi said:

 

Now I wanna see orion pusher plate spaceships shot out of a cannon on a mountain!

In KSP..  since that is safer?

Are space suborbital cannons and spin launch a thing in KSP?

Should be if not.

 

Someone probably will shoot stuff directly into orbit LOL

i figure the  warhead option would be for high payload situations. building a pressure vessel that can withstand the forces of what is essentially a nuke pumped steam boiler is no doubt going to be a very interesting design challenge. id love to see the engineering involved. 

[Spacescifi]

9 minutes ago, Nuke said:

i figure the  warhead option would be for high payload situations. building a pressure vessel that can withstand the forces of what is essentially a nuke pumped steam boiler is no doubt going to be a very interesting design challenge. id love to see the engineering involved. 

 

The fun irony is that I read that Jules Verne criticized HG Wells story about using an antigravity spaceship to reach the moon BECAUSE it was not realistic.

I guess Jules Verne was a hard scifi kind of guy.... funny to think the more tech changes the more people stay the same.

He would no doubt have loved to see Gerard Bull's space cannon launches... which they did about 200 of them or so.

 

Probably would have been sneering at HG Wells the whole time though lol.

 

Edited November 30, 2021 by Spacescifi

[magnemoe]

15 hours ago, DDE said:

I believe centrifugal machine guns have always been the poor man's gauss cannons and railguns.

But I also know that after that one guy began slapping spaceships together in a parking lot, I've learnt to have a little faith.

People has build centrifugal machine guns. Downside is that you can not use rifled bullets and even for round shots you accuracy is bad as release time affect direction. 
Yes you has very high rate of fire pretty simply but an using an gattling gun or an group of standard machine guns works just as well and can also engage long range targets. 
Centrifugal machine guns would make some sense on the early steam powered ships back then you only had black powder and boarding action was an concern. 

[magnemoe]

3 hours ago, Spacescifi said:

The fun irony is that I read that Jules Verne criticized HG Wells story about using an antigravity spaceship to reach the moon BECAUSE it was not realistic.

I guess Jules Verne was a hard scifi kind of guy.... funny to think the more tech changes the more people stay the same.

He would no doubt have loved to see Gerard Bull's space cannon launches... which they did about 200 of them or so.

Probably would have been sneering at HG Wells the whole time though lol.

Gun launch is possible, not an manned launch however and  Jules Verne knew that.  And how did Jules Verne knew anti gravity being impossible back then? 
And agree that  Jules Verne was more of an hard scifi than HG Wells.

[kerbiloid]

Imho, JV was more of data sheets and calculation for calculation. More a raw data collector than a writer like HGW.

Most of his fi is just a sci-looking heap of gathered facts.

[kerbiloid]

Maybe, start from something less fantastic?

Say, a lunar medieval castle (printed from regolith dust) with trebuchets to conquer the Earth?

[Superfluous J]

2 hours ago, magnemoe said:

And how did Jules Verne knew anti gravity being impossible back then?

The same way we know it.

i.e., he didn't, but it sounded as preposterous in his day as it does in ours.

[Meecrob]

19 hours ago, Superfluous J said:

The same way we know it.

i.e., he didn't, but it sounded as preposterous in his day as it does in ours.

Its simple logic...you cannot use an anti-gravity device to go to a place that has gravity

[K^2]

On 11/29/2021 at 4:00 PM, Nuke said:

i still like the idea that if you can loft a rocket to the point where a vacuum nozzle gives you better performance than a sea level nozzle you can do away with the first stage.

Getting 2km/s from the ground isn't a stupid idea. Combine it with a skyhook and you can do away with a rocket all together. Spinlaunch just happens to be the worst way to do it.

[sevenperforce]

12 hours ago, K^2 said:

Getting 2km/s from the ground isn't a stupid idea. Combine it with a skyhook and you can do away with a rocket all together. Spinlaunch just happens to be the worst way to do it.

I struggled to come up with a worse way.

I’ve always liked the idea of Black Horse. If the SR-71 needs to refuel immediately after takeoff then why not do the same with a much higher-energy aircraft?

I wonder if that idea could be modernized with a hybrid engine. The challenge was always the use of HTP, which is just a very dense oxidizer but not a very high-energy one.

But a lot of people assume that getting high is enough to do away with the first stage. It isn’t. The first stage lofts the upper stage quite high, yes, but it also provides it with a significant amount of dV, enough that the upper stage doesn’t need high thrust any more. 

[magnemoe]

4 hours ago, sevenperforce said:

I struggled to come up with a worse way.

I’ve always liked the idea of Black Horse. If the SR-71 needs to refuel immediately after takeoff then why not do the same with a much higher-energy aircraft?

I wonder if that idea could be modernized with a hybrid engine. The challenge was always the use of HTP, which is just a very dense oxidizer but not a very high-energy one.

But a lot of people assume that getting high is enough to do away with the first stage. It isn’t. The first stage lofts the upper stage quite high, yes, but it also provides it with a significant amount of dV, enough that the upper stage doesn’t need high thrust any more. 

Coil gun and  traditional artillery is two options, an supersonic plane with an rocket mode is another. Make something like an fat B-70, with extra fuel and LOX, you don't care about range you want to get to mach 3 then fire the rocket engine get to mach 6, deploy second stage and decent and return.  I say its an shame SAM's and ICBM worked as well as it killed the interest for fast high flying military planes. 
Making them more an dead end than battleships who while not front end units was still useful over an generation later. 
 

[sevenperforce]

1 hour ago, magnemoe said:

Coil gun and  traditional artillery is two options, an supersonic plane with an rocket mode is another. Make something like an fat B-70, with extra fuel and LOX, you don't care about range you want to get to mach 3 then fire the rocket engine get to mach 6, deploy second stage and decent and return.  I say its an shame SAM's and ICBM worked as well as it killed the interest for fast high flying military planes. 

Coil guns have diminishing returns and put some rather significant constraints on the magnetic properties of the projectile. Traditional artillery has such high gee-loading that it eliminates anything other than a solid-fueled rocket. Railguns are more versatile than coil guns but have the annoying requirement of extreme forces on the rails and requiring metal-metal contact the entire time.

What you're describing sounds not unlike Black Colt. A fairly small airplane with modest jet engines takes off carrying payload and COTS kick stage in its payload bay. It carries LOX in its tanks and just enough JP-5 to get off the ground and up to about Mach 0.8, which is where it performs aerial refueling from a KC-135Q and its tanks are filled with JP-5, JP-7, or RP-1. It then lights a rocket motor, burns to Mach 8 or so, releases its payload and kick stage, and then coasts back to base. So it's really more like a 3-stage vehicle but everything is reusable apart from the kick stage.

[sevenperforce]

There are a couple of ways to use ground infrastructure to amp up the Black Horse concept. For example, you could design a long, angled electromagnetic or steam catapult on the side of a mountain, thus eliminating the need for (a) GTOW-bearing landing gear, (b) takeoff propellant, and (c) a high subsonic L/D ratio. So that brings your dry mass down. You can also add LOX drop tanks, both to reduce the mass to orbit and to further take advantage of your catapult.

The airplane would take off with mostly-empty fuel tanks (reducing the amount of lift needed) and climb on turbine-based combined-cycle (TBCC) engines (operating in turbojet mode) to altitude, where they would meet a KC-135Q and fill up the fuel tanks. Firing the engines in sc/ramjet mode takes it up to Mach 5 and then burning the remaining fuel with LOX in an vacuum-optimized nozzle takes you nearly to orbit. Drop the LOX tanks and circularize with hypergolics.

[K^2]

11 hours ago, sevenperforce said:

I wonder if that idea could be modernized with a hybrid engine. The challenge was always the use of HTP, which is just a very dense oxidizer but not a very high-energy one.

That's it. This is how we do it. A solid or hybrid motor rocket takes off as normal, and we fire fuel for its second burn out of a cannon timed for them to meet at some point during ascent. You get "gentle" acceleration for the cargo, making it potentially viable for human launches, and you still get to avoid building a massive first stage.

[sevenperforce]

11 minutes ago, K^2 said:

That's it. This is how we do it. A solid or hybrid motor rocket takes off as normal, and we fire fuel for its second burn out of a cannon timed for them to meet at some point during ascent. You get "gentle" acceleration for the cargo, making it potentially viable for human launches, and you still get to avoid building a massive first stage.

........and did we just reinvent the space fountain?

[K^2]

2 hours ago, sevenperforce said:

........and did we just reinvent the space fountain?

Sort of? But without need for maintenance. Not much of a fountain if you just yeet one piece of infrastructure per launch.

[linuxgurugamer]

7 hours ago, K^2 said:

That's it. This is how we do it. A solid or hybrid motor rocket takes off as normal, and we fire fuel for its second burn out of a cannon timed for them to meet at some point during ascent. You get "gentle" acceleration for the cargo, making it potentially viable for human launches, and you still get to avoid building a massive first stage.

This is a joke, right?

[sevenperforce]

2 hours ago, linuxgurugamer said:

This is a joke, right?

Yes, yes it is.

Although it does sound a little like the idea of a seeded Bussard ramjet.

[K^2]

8 hours ago, linuxgurugamer said:

This is a joke, right?

Like, 95% joke, 5% "Wouldn't it be cool, though?" And I seriously think it would be a better startup than Spinlaunch. At least, it aims to do something you can't do with another method better already.

[sevenperforce]

28 minutes ago, K^2 said:

Like, 95% joke, 5% "Wouldn't it be cool, though?" And I seriously think it would be a better startup than Spinlaunch. At least, it aims to do something you can't do with another method better already.

Or if you could find a way to use a supergun of some kind to produce a persistent, coherent plasma beam which the payload could ride into space. Like a rainbow bridge.