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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,368

Magnetic Launch Electromagnetic Launch Rail Gun

SpaceNut ... there was no topic that matched the above combination ...

To lead off, here is a bit of a report on the US Navy giving up on Rail Gun technology for military operations ...

The system, while capable, is (apparently) insufficient to defend against first tier adversaries.

In retirement, I am hoping this system might be considered for launch of supplies (including fuel and oxidizer) into LEO.

https://www.thedrive.com/the-war-zone/4 … et-request

"Railgun technology and knowledge attained will be documented and preserved," according to a separate section describing the purpose of the extra funds Congress added to the program in the 2021 Fiscal Year, further indicating that the plan is now, at best, to shelve the project indefinitely. "Railgun hardware will be realigned to maximize its sustainability to facilitate potential future use."

The War Zone has reached out to ONR for further information on the exact fate of the railgun program and how it or other entities within the U.S. Navy or elsewhere across the U.S. military might leverage any of the project's existing work.

This technology might be capable of launching fuel cannisters into LEO from Texas.

Each cannister would need to be fitted with a solid fuel rocket to achieve horizontal velocity, but the rail gun ** may ** be able to put the cannister at the right altitude for a fuel depot.

(th)

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,431

Re: Magnetic Launch Electromagnetic Launch Rail Gun

We have talked about it in a mass delivery systems such as slinging stuff to orbit on the moon of from asteroids but the version which the military has worked on is still not quite as capable as one wants in a war perspective....
The eml (electrical magnetic launcher) launcher is a version with planes that we thought might be convertible to small rockets boost but the size and energy were the issues....

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,431

Re: Magnetic Launch Electromagnetic Launch Rail Gun

bump

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,431

Re: Magnetic Launch Electromagnetic Launch Rail Gun

Military is or does appear to be still working the bugs.
The Railgun: The Ultimate Weapon the U.S. Military Can’t Build?

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,368

Re: Magnetic Launch Electromagnetic Launch Rail Gun

Back in January, in Post #4, SpaceNut showed us a link to a report on rail guns. Recently I read an article on the status of rail guns as they are being developed and tested by the US Navy.  Today I decided to ask ChatGPT(4) to look at the situation, and specifically to compare rail guns (which have distinct advantages) to coil accelerators (which have distinct advantages).  Each concept has distinct disadvantages. I asked ChatGPT to look at the situation, to see if there might be melding or merger of the two designs.

Here is a link to the transcript:

https://docs.google.com/document/d/19Os … sp=sharing
The session ended prematurely due to a network error, but I thought there was enough already generated to be worth showing to NewMars members.

The most promising solution that was in development before the network error was self-healing rails.

Coil accelerators do not have the rail wear problem, but they ** do ** require precise timing of impulses, which the rail gun design does not.

(th)

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,368

Re: Magnetic Launch Electromagnetic Launch Rail Gun

As a follow up observation ...

The US Navy needs to be able to orient the rail gun system to a low elevation.

However, a vertical mass launcher needs to be able to orient the acceleration pathway to the near vertical, or at most 45 degrees off vertical. This difference would (or could) allow the mass accelerators to employ buckets of soft metal as the "rail" of a rail gun.

The main problem faced by rail gun designers appears to be wear of the rails.

For a mass driver (such as for a propellant launcher for Dr. Johnson's refueling station) the launch angle can be somewhere between vertical and 45 degrees off vertical.  I think it might be worth looking to see if the "rails" can be made of self-healing components.

The rail gun design appears to have significant advantages over Dr. O'Neill's coil accelerators, due to the raw simplicity of the design.

(th)

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,431

Re: Magnetic Launch Electromagnetic Launch Rail Gun

Well, a test has happened Japan's Railgun Performs First Test Firing At Sea

can see the electric cables are spaced in a linear distance.

looks like a plasma comes out of the barrel...

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,368

Re: Magnetic Launch Electromagnetic Launch Rail Gun

This topic has been quiet since the report by SpaceNut of the Japanese rail gun...

Today's Internet feed contained news of Chinese thinking about a more substantial effort by the Chinese...

This appears to be more than just a paper study .... the Chinese have a facility they've been using to test maglev trains, and apparently they are thinking on a larger scale, now that maglev trains are pretty much a solved problem there.

https://www.msn.com/en-us/news/technolo … 2810&ei=78

China plans to build a giant rail gun to launch hypersonic planes longer than a Boeing 737 into space - as Beijing ramps up race to the moon
Story by Taryn Pedler • 10h • 3 min read

Scientists had to make compromises in aerodynamic design and engine layout
The tech could reduce launch costs to a fraction of the current price
The hypersonic planes will be able to travel at almost twice the speed of sound

Chinese scientists are working on constructing a giant electromagnetic rail gun that will be used to launch 50 tonne hypersonic planes into space.

Engineers and scientists in China have been working on the project - named Tengyun - since 2016, but following a recent series of significant advances made in both electromagnetic launch and hypersonic flight, they believe that soon, people could be sent into space.

The rail gun will essentially be a giant electromagnetic launch track used to accelerate a hypersonic aircraft to Mach 1.6 - meaning it will be travelling at almost twice the speed of sound (Mach 2).

Weighing 50 tonnes, the mammoth planes are set to be longer than a Boeing 737 at over 129 ft.

Following the launch, the aircraft would then separate from the track, ignite its engine and enter space.

Scientists and engineers in China are working together to create a new space launch method that combines hypersonic flight and electromagnetic launch technology

Scientists and engineers in China are working together to create a new space launch method that combines hypersonic flight and electromagnetic launch technology

© Provided by Daily Mail

If the project is successful, the new technology could reduce launch costs to a fraction of the current price.

This makes it an attractive piece of technology for companies such as NASA and SpaceX - who still haven't cracked the code to successfully building an electromagnetic launch to this scale.

But creating these futuristic machines hasn't been simple.

Relying solely on the plane's own power for lift-off would require a significant amount of fuel and the team also faced difficulties in finding a way to combat the dangers of a low-speed take-off.

Engineers and scientists were then forced to make compromises in aerodynamic design and engine layout that affect the machines high-speed flight efficiency.

This is not the first time China have put forth projects of this nature - although many of them did not leave the drawing board.

But this time the scientists working on the Tengyun project are confident the current issues they are facing can be solved.

'Electromagnetic launch technology provides a promising solution to overcome these challenges and has emerged as a strategic frontier technology being pursued by the world's leading nations,' wrote team lead scientist Li Shaowei, in a paper published in journal Acta Aeronautica on February 6.

To test the theory, China Aerospace Science and Industry Corporation (CASIC) will be using the 1.2 mile long low-vacuum track high-speed maglev test facility in Datong.

Tests will be carried out at 1.2 mile long low-vacuum track high-speed maglev test facility in Datong, generally used when researching magnetic levitation train technology

© Provided by Daily Mail

The original purpose of the lab was to provide a key test platform for the low-vacuum tube magnetic levitation train technology.

But because the facility can propel heavy objects to speeds of up to 1,000km/h, scientists are now using the base for aerospace testing.

Within coming years, the Datong test facility will be extended to 37.2 miles long, to achieve a maximum operating speed of a staggering 5,000km/h.

The lab is considered one of the most 'ambitious electromagnetic propulsion facilties on the planet' according to SCMP,  which is why it will now be used to gather crucial scientific data for the space electromagnetic launch project.

China is not the only country to explore the creation of an electromagnetic space launch system and hypersonic planes, with NASA and the US Navy previously attempting to successfully bring the concept to life.

In the 1990s, NASA tried to build a mini test line of 49ft but only managed to complete around 32ft due to technical difficulties and lack of funds.

The ambitious project was eventually scrapped and military officials put their resources towards developing low-speed electromagnetic catapult technology instead.

The US Navy implemented the technology into the USS Ford but have publicly acknowledged the high failure rate of the electromagnetic catapult system.

Now, the US has shifted its focus once more, to work on the development of rail guns and hypersonic missiles.

China is continuing to make breakthroughs in their electromagnetic rail gun research, however, staying ahead of the game with their high-performance power supplies, precision control technology, and the development of electronic devices capable of resisting strong electromagnetic interference.

(th)

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Magnetic Launch Electromagnetic Launch Rail Gun

News reports say Chinese fired some type of shell or smart bomb into stratosphere but the test was classed as a failure

'China Uses Giant Rail Gun to Shoot Smart Bomb Nine Miles Into the Sky'
https://www.yahoo.com/tech/china-uses-g … 41470.html

How Maglev Trains and High-Speed Rail are Revolutionising Travel
https://knowhow.distrelec.com/transport … ng-travel/