Mag Lev Assist Rockets

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

Well it looks like I’m about 7 years too late on this concept! Based on that article from 2011

why aren’t we doing this?

I have a few guesses:

• Stopping the sled so you can reuse it afterward. If the payload is going fast enough at the end of the track to assist a satellite launch then the sled will be going just as fast, too.
• Cost of the land. Moving horizontally first will take up more land.
• Moving horizontally means fighting air drag longer.

Virgin Galactic intends to use a carrier plane approach to raise a rocket plane to a higher altitude and velocity.

Great Points,

My thought was to make the rocket the sled. This portion would be reused when the rocket returned.

(Don't know the condition of the rockets sled portion upon re entry)

cost of land : 3 miles of land flat or otherwise = 5- 7 miles of track, depending on the pitch. the thought was in boring under ground. (I guess impossible in Florida.)

Moving: true, but with the Mag Lev driving horizontal ( with help from the boosters at minimal thrust) until vertical release where the main boosters take over. ( track in an inverse arch, of sorts...)

Structural stress on the rocket might make this a non-starter...

The trip down the mag lev track may just erase a LOT of stored data in memory devices.

Maybe even guidance devices that become charged by magnetic pulses.

Isn’t there mag plate that resist magnet pulse?

If you, "make the rocket the sled," where would that "mag plate' be?

Having worked on covert satellites, I can say that they are EMP hardened. But sustained exposure to strong, local magnetic fields may defeat these measures.

Just saying.

Although I will say I do not know the specifications of the magnetic drive pulse of a magnetic levitation device, would this not be extremely lower than an electrical magnetic pulse?

I have not heard of anyone riding mag lev trains losing data on their laptops or any other electronic devices.

How would you make the rocket the sled?

These are not light in weight...

..."Weight: The electromagnets in many EMS and EDS designs require between 1 and 2 kilowatts per ton.^[60] The use of superconductor magnets can reduce the electromagnets' energy consumption. A 50-ton Transrapid maglev vehicle can lift an additional 20 tons, for a total of 70 tons, which consumes 70–140 kW (94–188 hp).^{[citation needed]} Most energy use for the TRI is for propulsion and overcoming air resistance at speeds over 100 mph (160 km/h).^["...

^{https://en.wikipedia.org/wiki/Maglev}

Saturn rocket is 33ft in diameter 363 ft high, and weighs 6,540,000 lb...

That's you standing at the base.....Yeah, it's really big...

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

Go big or go home right!

if we can lift a train we can lift a rocket!

Lifting and throwing are two different things...

Critique of this concept? Combination of vacuum ala hyperloop and magnetic assist, but oriented vertically in a very deep shaft. The rocket would have retractable fins that engage with the maglev rails. To counter atmospheric inrush at the exit, the tunnel would be shortened by Iris gates along it's length as the rocket passes.

"... To counter atmospheric inrush at the exit, ..."

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Awww....don't do that. Why waste all that energy? Just vent from the very back/beginning of the launch tube a little before the rocket reaches the frangible exit seal at the top and let the inrush open it...and provide an extra boost.

Sure, why not let the atmosphere rush in behind it? But not so sure how frangible the exit could be, b/c according to what I've read you'd have 10,000kg per square meter of atmospheric pressure trying to permeate that barrier in a near perfect vacuum--such as that proposed by the hyperloop.

The opposing pressure shouldn't detract significantly from a bartrer being frangible under likely conditions.

At any rate, if you vent from the back with timing sufficient to gain a boosy, the pressure across the barrier will be, at least, far reduced, perhaps reversed, by the time the vehicle reaches the barrier.

With the right design and control, the vehicle wouldn't be meaningfully impacted by the seal.

But that will require a rocket hull with the tensile strength of unobtanium. Do you know how expensive this stuff is?

Con someone please go to Pandora...

we need unobtainium...

Well, either unobtainium or maybe just some fairly run of the mill engineering to utilize a discarding sabot / wadding to protect the less robust rocket hull.

Regardless of how many wads of tissue paper were in the toes, why would anyone discard French shoes made of unobtanium?

Well, certainly no saboteur. How could one sabotage without sabots?

My thought was not for hyper loop, in rush at exit would be too hard to overcome.

more like a train through a tunnel. With doors closing behind it as it passes through.

The inrush would only be something detracting (something to overcome) if it were vented from the forward direction.

Hmmm...Ballistic nuclear subs launch missiles from a dry tube thru water. They must have some kind of a frangible membrane.

..."How missile is launched from submarine?

It's fired by a steam cannon. First, an explosive charge flash-vaporizes a tank of water into steam. As the pressure of the expanding steam drives the missile out of its launch tube, it provides enough momentum for the weapon to clear the water's surface."...Feb 13, 2017

https://www.popularmechanics.com/military/weapons/a25176/launching-missile-from-submarine/

Nice stuff, Solareagle. The small clip appears to show a hemispherical cap that shatters when the missile launchs.

Let's get even simpler...how about a belt system powered by electric motors connected via a CVT. How fast could it get a certain mass moving over a given distance?

Also, would you even need a vacuum? If you pumped the air from above the launch shaft into the space below the projectile, that would seem to overcome a lot of drag resistance.

Reminds me of the movie When Worlds Collide where the spaceship was boosted by a rocket sled along a track that curved up a hill. It looked good at the time...

Haha....classic 1951 scifi

As crazy as this looks, Put a Mag Lev in place of the rails !

Throw a tube around it with some doors that close behind it , and viola!!!

The concept as a whole. Except not up the side of a mountain. or why not...

the downward thrust from the mag lev will propel the rocket exiting the end of the track around 800 to 1,000mph, then the main rocket boosters kick in. that just saved you 50 seconds or more of burn tome.

But why are we stuck on a track? A rocket and payload weighs the same whether oriented horizontally or vertically, right? We're trying to get out of the atmosphere as quickly as possible without having to correct trajectory unnecessarily, thus saving fuel weight.

The thought was to eliminate the excessive boost needed to reach escape velocity.

The track was to use electromagnetic propulsion, eliminating the need for the weight of the fuel needed to reach the same speeds, decrease fuel capacity on launch, almost eliminating the need for a primary booster. This has the same fuel mass results when reaching low earth orbit as current means.

When the track curves downward, it will increase the speed by simple gravitational pull. When the track curves back upward the boosters will start when the rocket is already at 500 mph (est.)

Again, the thought was to use A LOT less fuel to reach escape velocity.

Have you ever tried to take a corner at 500 mph, straight up, in a 6 million lb rocket??? I'm guessing you would be crushed by kinetic energy....and then some...Speed has no advantage unless it is in direct opposition to the gravitational force....This is a rocket with no wings to fly like an airplane...speed for a takeoff only helps if you have wings....

"Have you ever tried to take a corner at 500 mph, straight up, in a 6 million lb rocket???"

No, I have not And I am guessing you have not either. And this is not an airplane?

kinetic coefficient of friction on an inclined plane removed,

Did you not read the initial thought/ question?

I believe what you are wanting to ask is what would the negative G forces be in a moving object changing trajectory from a decline to an incline at a set speed?

I believe that would be Ek = 1/2 mv². Think of a pendulum.

Great pictures and insight for an off subject comment. Of which I am trying not to take personally.

If I had wings I would already be flown far far away from here.

Why do you think the coefficient of friction of an inclined plane would magically disappear? Oh, I get it. You think the magnetic repulsion would always be sufficient to separate the magnets. The vertical field magnets on a maglev train match the force of gravity on the train by finding the equilibrium point since the force is roughly proportional to the inverse of the gap squared. However, this is not really just a simple second-order equation relationship for cores do quench and an absolute maximum force between magnets does allow the magnets to touch. I suspect the magnets will collide at some point, energy will be lost and magnets may be damaged. Thus the energy needed to change horizontal motion into vertical motion will be more efficiently used in moving upward in the first place.

Thank!

that makes sense!

6,000,000 lbs @800 mph = 128,368,468,335 ft-lbs

Who can tell me how long it takes this vehicle to get up to speed and the necessary runway length?

No shade cast upon you guys, but why does any theoretical proposition always end this way? No it's me ever asks themself, "Why not?"... it's always, "Because that's the way it is currently."

If unobtanium were ever really needed to penetrate a barrier...

<<<still unhappy about the grounding of the flying car.

I'm sure there is nobody here saying that it shouldn't be done because that's not the way it's always been done, we're saying it can't be done because it's not possible...

https://www.evolving-science.com/environment/flying-car-00801

Exactly my point. Before the turn of the 20th century, how many things we take for granted today were thought to be either impossible or even so "far-fetched" as to be unimaginable?

What would this craft do if it left the water and went into land? Likely, the same.

What I'm saying is--to skip a step--to take advantage of ground effect, you don't need wings. Most of the aerodynamic engineering of high-speed vehicles on air or water is currently in concerned with making them adhere to their respective surfaces.

In other words, to prevent them from flying. Once you've left the ground you're flying in a sense...regardless of your altitude or ability to control that flight.

Then I brought up the flying lawnmower--where are it's wings? It has none.

What is it that is so dissimilar from a car that it would make one believe a flying car is totally incredulous? It's certainly very dissimilar from an airplane or your typical flying car designs-- which are honestly cars with wings or helicopter rotors.

"... What would this craft do if it left the water and went into land? Likely, the same. ..."

When discussing flying vehicles, going 'into the land' is commonly referred to as crashing. So damage and injury may be likely.

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"... Then I bought up the flying lawnmower--where are it's wings? It has none. ...."

The rc plane in the video you link definitely has wings, in fact it is probably best described as a sesquiplane (not quire a biplane, closer to one and one half wings).

The fact that the wings are disguised as parts you recognize as the engine cover and deck of a lawn mower doesn't mean there are no wings, only that you were fooled.

Lest you think I don't appreciate the spirit of your rant (in spite of the content), I'll leave you with this quote, the first of the three laws of Arthur C Clark:

"... When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong. ...."

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(Now if you can just determine if your detractors are 1. Elderly, 2. Distinguished, and 3. Scientists perhaps this law might be of use.)

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Meant to say onto the land, but I think you knew that.

No, I was not fooled. I saw the "engine cover". I also saw the "handle" , which you did not mention. They are, or should be, primaily control surfaces. A "wing" however, is generally thought of to be something that protrudes from a body.

Most of the lift and flight stability can undoubtably be attributed to the flat, skirted, underside...but you couldn't really say that's a wing by classic definition. So how is that so far removed from the underside of a car?

Many cars--most of which today are already shaped like an airfoil and generate considerable lift as they are--have rear wing spoilers...what would occur if you add a canard-like second wing in the front? Is that too difficult to envision?

Because my thoughts Ideas and hypothesis are not your own don’t discredit them.

“My hypothesis is not only not right; it is not even wrong.”– Wolfgang Pauli

To Have an Idea of what may be possible. To change the falsehood of knowledge. To not under-appreciate the narrative of anything is possible. This is what I am teaching my children. To change the world for the better there must be growth in the impossible. Dream big, work hard and make it happen…

argumentum ad ignorantiam

If you can't flesh out an idea, then it's just a dream....dream on if it suits you , but no reason to disparage those on terra firma...

I thought that was what this was?

A "fleshing out", an Idea, a question, on the enhancement of someone else's DREAM they made a reality, posted in a communicative forum?

And I believe you have it reversed! there is no reason for you to disparage those that do dream big, with our heads in the clouds...

You may consider yourself a realist ,(I'm sure that is coming in your next negative comment), as do I, the difference is I will try, I haven't given up! I'm not relaxing on a beach yet, or just grumpy!

I encourage you to dream big, but that doesn't mean you can escape reality completely....

But do you know?-- I can flesh them out.

I just seem to have difficulty accessing the tools to do such with opportunity. So here's a crude representation of the flying lawnmower that looks more like a flying car. Imagine the tube in the middle is a turbine. What is so divergent and far-fetched about it?

Is this an autonomous zero-passenger flying car? (I suppose if a box car can still be a type of car without being meant to carry people, then your flying car could without carrying people.)

If you don't take that easy way out, and your flying car is meant to transport people, where in your drawing are the people stowed during flight?

If you intend the people to fit in the white trapezoid prism, you will need to begin a breeding program to develop a teacup strain of people as your target audience or alternately start lobbying to double current lane widths for the monsterous size of your flying mower car.

...and that's just the current scale, who knows how wide it would have to be to fly reliably.

I did that on my phone in a few mins. with an app called Spacedraw..and as I were saying... it's crude. But so what? I was just providing a general visual.

A paper airplane "flies"...and I suppose if you made a big enough one you could sit in it. It's a long way from being a commercial airliner, but you couldn't dismiss it as being just a wad of cellulose.

With a copy of SolidWorks, adequate time, and a 3-D printer, I'm quite certain I could have a scale model virtually indistinguishable in proportions and general look from a passenger car and put Larry and Vince in there and take off.

But in this forum, once a few of you guys decide to shoot down an idea though, nothing--not even an actual bird--seems to be able to take flight from there.����

My criticism was not of build material. You specified none.

My criticisms are legitimate yet you did not respond to the actual criticism.

'Flying cars' would presumably need to house and support the bulk and weight of human passengers as well as equipment necessary for things like propulsion and control. The possibility of doing this within the constraints of something that is legally and functionally toad worthy and airworthy is not trivial. It is certainly not something for which a rendering reminiscent of minecraft (with essentially zero additional useful elaboration) could sufficiently describe.

I feel like Elon Musk's unveiling of the cyber truck may have skewed your view of what might pass as a reasonable presentation vehicle proposed for production.

When using a quote from someone famous, especially when the quote is about being wrong, investing a little extra time against the irony of the quote itself being wrong, would have been wise.

You wrote:

"... “My hypothesis is not only not right; it is not even wrong.”– Wolfgang Pauli ..."

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I have seen some variations on this quote, but none referenced Pauli's own work as the object of the scorn. Pauli was well known for his aserbic tongue when berating ideas he found developed on the basis of lazy thought, but I have never heard of an instant when he degraded himself in such a way, so I find it improbable that the quote you present is accurate.

I am open to learning something new on the subject. Will you enlighten us as to your source for the quote?

WOW ,A new impromptu criticism from a different gallery.....

With the quote from Pauli I ASSUMED the narrative was met, guess not.

I referenced myself in his quote. Apparently not as obvious as I thought.

“I do not mind if you think slowly, but I do object when you publish more quickly than you think.” ..

Criticism is the rudder of creativity...