The electro-magnetic gun program gets US$14.7 million

Gizmag ^ | 7/7/06 | Gizmag

[Reaganesque]

July 7, 2006 The United States Navy has awarded two contracts for the development of an electro-magnetic gun system capable of deployment on board naval surface combatant ships. The development work preliminary design for an Electro-Magnetic (EM) railgun prototype and the preliminary design of the U.S Navy's 32 megajoule (MJ) Laboratory Launcher. An electro-magnetic railgun uses electrical energy to accelerate projectiles to extreme velocities. Railguns do not require powders or explosives to fire the round and therefore free magazine space for other mission areas. In addition, electro-magnetic guns provide a highly consistent and uniform explosive charge that gives much greater accuracy. Thirty-two megajoule is equivalent to a firing speed of Mach 8 or eight times the speed of sound. This will be an intermediate step on the road to a 64-MJ Tactical System capable of deployment on-board naval surface combatant ships.

The development work includes a US$9.3 million contract from the Office of Naval Research (ONR) to develop technologies and preliminary design for an Electro-Magnetic (EM) railgun prototype and a US$5.4M contract from Naval Special Warfare Center-Dahlgren for the design and fabrication of the U.S Navy's 32 megajoule (MJ) Laboratory Launcher.

BAE Systems was selected by ONR to advance to the next phase of the Innovative Naval Prototype Program. Under this 30-month phase, BAE Systems will take the state-of-the-art Electro-Magnetic Railgun technologies through technology maturation and develop a preliminary design of a 32-MJ EM Railgun. Thirty-two megajoule is equivalent to a firing speed of Mach 8 or eight times the speed of sound. This will be an intermediate step on the road to a 64-MJ Tactical System capable of deployment on-board naval surface combatant ships. The design and fabrication of the 32-MJ Laboratory Launcher will serve as a major step towards development of a full-scale tactical EM Gun weapon system for the U.S. Navy.

[Sergio]

Thanks for the reply, I thought that the projectiles might have to be made of "unobtainium" or some other highly expensive alloy.

Then again, at the speeds we are talking about, I would think that it wouldn't take much mass to be extremely effective.

[TalonDJ]

It should be obvious that this gun is meant soley for use on nuclear powered craft.

Nuclear powered craft do not have massive amounts of more power available as compared to turbine or diesel craft. That is a misconception.

[GSlob]

It would take a lot of mass to be effective at reasonable distances: air starts slowing the projectile immediately - regular mach 3 bullet [ballistic coefficient 0.56] after 1 km retains only about 50% of its velocity. Thus one needs to build a projectile with a very high ballistic coefficient - and this translates into a massive thin needle-like projectile. If you throw it at 2.5km/sec at something few miles away, by the time you hit it it would be flying much slower.

[jrd]

looks like we are going back to the Philadelphia experiment!

[TalonDJ]

In real life a rail gun Some experimental railguns fire plasma. Ones that use conductive rails instead of magnetic coils tend to vaporize the projectil because all that power is going through it. They have discovered that so much energy in a moving ball of plasma forms a magnetic field and the plasma tends to become a moving toroid shape.

[RobRoy]

>>It should be obvious that this gun is meant soley for use on nuclear powered craft.<<

Didn't the article say it needed four AAA batteries?

[TalonDJ]

The gun is supposed to be on a nuclear powered naval ship.

Not true. They are looking to put it on turbine powered destroyers.

[RobRoy]

>>It should be obvious that this gun is meant soley for use on nuclear powered craft.<<

"One point twenty one jigawatts?! Tom, what was I thinking?!!"

Ok, name that movie...

[RobRoy]

man, you guys were WAY ahead of me...

[Erasmus]

Scaled-down airplane window tester.

[RobRoy]

>>BB's at 15000fps at 6000rpm<<

You'll put your eye out kid.

[Erasmus]

If a modern ship's electrical and/or electronic systems get knocked out, there are no weapons of any kind that will work, beyond the crew members' model 1911s.

In regard to the claim about the railgun being only for nuclear wessels, I don't see why. If you do the math, even conventional steam powered ships can be designed to come up with enough juice to run the gun.

[ASOC]

There are several in the series and many related to the series

Redliners
Butchers Bill
Point of the Spear
and one that is unrelated, but just funny
All the way to the Gallows

Enjoy - and look for more as it would seem David will assume more of the load an Baen Books.

[USFRIENDINVICTORIA]

Exactly what I was thinking. A bit sloppy for a tech publication.

[WLR]

Actually small charges were being used last time I checked to force the circuit completion. The problem that has been most difficult is the trigger mechanism melts to slag when fired. It is basically a giant magnet which only actuates for a millisecond. That much juice tends to blow things apart where the connection occurs.(Think how much fun it is to cross positive and negative wires on your car battery now multiply that by a Bazillion (scientific description). So you can see you have some arc and melting problems in that environment.

W

[Zebra]

A depleted uranium round would do just fine.

[El Laton Caliente]

Would that be the "Hammer's Slammers" series of military sci-fi novels/short stories... I can't recall the author right now.

[2harddrive]

Rail guns have ZERO explosive power! They are NOT firearms. Period.

[Reaganesque]

I had read this earlier about new nano-tech, ultra capacitors. Perhaps this has something to do with the Navy's decision? From February's Gizmag:

February 14, 2006 Almost everything we use requires electrical storage via a battery - computers, cell phones, cars, personal entertainment devices and much more – and as compelling functionality has increased in the digital age, so too has our reliance on the traditional battery which has changed little since it was developed by Alessandro Volta in 1800.

Now, work at MIT's Laboratory for Electromagnetic and Electronic Systems (LEES) holds the promise of the first technologically significant and economically viable alternative to conventional batteries in more than 200 years. Using nanotube structures, the LEES invention promises a significant increase on the storage capacity of existing commercial ultracapacitors by storing electrical fields at an atomic level.

The new LEES ultracapacitors could replace the conventional battery in everything from the smallest MP3 players through to electric automobiles and beyond, yielding batteries with a lifetime equivalent to the product they power and recharging times inside a minute. Most significantly, they promise a much smaller and lighter “battery”, and will be an enabling technology for many new concepts such as electric bicycles with the “burst” peak power of a motorcycle, or electrical trams with the capacity of a train but without the infrastructure.

In automotive terms, they raise the possibility of an integrated starter/generator and the capability of ultra-efficient regenerative braking systems. The work was presented at the recent 15th International Seminar on Double Layer Capacitors and Hybrid Energy Storage Devices and the LEES “batteries” could reach market within five years.

[marktwain]

"A weapon of this type would not need to fire rounds that themselves had any explosive or incindiary properties -- the kenetic energy alone would do all the work; witness the saboted round fired by the 120mmm smoothbore cannon on the M1 Abrahms. And that's "only" 4000 fps -- much less than what is being described here. It would probably be difficult to create any such projectile that could withstand the incredible G forces in any case."

The G forces depend on the length of the rail. A mach 8 projectile is only going about twice as fast as the fastest conventional projectiles (9,000 fps vs 4,000 fps), so making the rail about three times as long (say about 3 yards) would give G forces about the same. Back before the Clinton administration, we had proof of concept rail guns that propelled projectiles at three times this velocity.

What is really interesting about the whole linear accelerator (which is what a rail gun is) business is its potential for making space flight so much cheaper. At 25,000 fps, we can file objects into orbit. Heck we achieved suborbital flights with big cannon! Sure we will not fire people into orbit with small linear accelerators, but we could send up food, water, fuel, air, construction materials... at a tiny fraction of the cost of doing so now by rockets. This would open up all of the solar system to industrial development.