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U.S. Navy Receives First Industry Built Railgun Prototype

Posted by Unknown on from the killing-pirates-with-magnets dept.

Zothecula writes "Two years after BAE Systems was awarded a US$21 million contract from the Office of Naval Research (ONR) to develop an advanced Electromagnetic Railgun for the U.S. Navy, the company has delivered the first industry-built prototype demonstrator to the Naval Surface Warfare Center (NSWC) Dahlgren. The prototype launcher is now being prepared for testing which is scheduled to take place in the coming weeks."

32 of 277 comments (clear)

  1. Wow by koan · · Score: 5, Interesting

    Can you imagine the sound this weapon makes when a projectile exits at 5000 MPH, that alone would terrify the enemy.

    --
    "If any question why we died, Tell them because our fathers lied."
    1. Re:Wow by vlm · · Score: 4, Insightful

      At mach one zillion and hundreds of KM away, they won't hear it until long after the dust settles from impact.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    2. Re:Wow by Anonymous Coward · · Score: 5, Funny

      The enemy would be terrified by the noise, but I suspect wouldn't risk much from the gun, as a projectile exiting the barrel (or whatever passes for a barrel in a railgun) at 5000 mph instantly vaporizes when it hits the atmosphere.

      You're thinking of Santa.

    3. Re:Wow by mdsolar · · Score: 4, Informative

      Actually no. The projectile survives. http://www.youtube.com/watch?v=6BfU-wMwL2U

    4. Re:Wow by Tim+C · · Score: 4, Insightful

      Perhaps, but not the enemy that it was aimed at - the projectile will get there before the sound does.

      --
      It's official. Most of you are morons.
    5. Re:Wow by Anonymous Coward · · Score: 5, Interesting

      I work at the facility in question. The sound is comparable (but louder) to a 5 inch shell being fired on the range.

      It is quite capable of startling someone not expecting it from about a km away.

    6. Re:Wow by Baloroth · · Score: 5, Interesting

      Well, TFA says the projectile travels at around 5,000mph leaving the barrel, and has ~32 megajoules of energy, so using KE=1/2mv^2 and some conversion, you get about 13kg (5000mph=2235m/s, [32e6]*2/[2235^2]=m=12.8)

      --
      "None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
    7. Re:Wow by PPH · · Score: 5, Informative

      If you've heard it, it means you've survived.

      The projectile will arrive before the sound.

      --
      Have gnu, will travel.
    8. Re:Wow by Captain+Hook · · Score: 5, Interesting

      I'm still unclear on how the rail gun is supposed to take accurate aim on a mobile target (another ship).

      Assuming you are shooting at 80 miles, the projectile is moving at 5000 mph. Flight time is about 58 seconds. Not many large ships can radically alter course in that time to avoid the shot.

      Also, bear in mind that line of sight at sea level +30 meters is about 13 miles. So a target ship without the ability to see beyond the horizon (either Airborne Radar or Satellite) only has 9 seconds from when the slugs appears above the horizon to impact, and thats assuming the radar picks it up the moment it's above the horizon.

      The US already has missile technology which does a very good job.

      Missiles can be shot down or guidance interfered with.

      There is also an issue with missiles and shells being filled with explosives which if detonated within your ship at the very least significantly damages if not out right sinks it.

      Railguns are shooting a solid slug of metal. There is no propellant to be ignited, it's intrinsically safe for the firing ship to handle. The slugs are also far more compact than the missiles or shells because of the lack of propellant so a warship can leave port carrying far more ammo which means less resupply at sea is needed.

      --
      These comments are my personal opinions and do not necessarily reflect the opinions of the other voices in my head.
    9. Re:Wow by clampolo · · Score: 3

      Hi. I live a km away from the facility in question. Please stop conducting your tests at 3am

  2. Re:Where's Gordon Freeman when you need him? by BergZ · · Score: 5, Funny

    Wasn't he supposed to be in the Test Chamber half an hour ago?

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  3. Re:Where's Gordon Freeman when you need him? by jeffmeden · · Score: 3, Insightful

    No, it's powered by zero point energy. Until now, there has been no practical application for the technology, but manipulating gravity for the purposes of propelling objects at high rates of speed at your enemies sounds like a winner. Hence, we will need Gordon since he is the only one crazy enough to put one in his hand for testing purposes.

  4. Re:Pop Up by osu-neko · · Score: 5, Funny

    There is an annoying popup on TFA. Reload to temporarily defeat it.

    Hmm, I don't see any popup. I suspect your NoScript settings are set to something insane, like "not installed"...

    --
    "Convictions are more dangerous enemies of truth than lies."
  5. Comments at TFA by mdsolar · · Score: 4, Insightful

    Some wish that we would put efforts into more peaceful technology. It is worth remembering that the German V2 research became the basis for manned space exploration both in the US and in the Soviet Union. Eventual space cooperation led to better arms reduction treaties. The rail gun may also have eventual launch applications and promote cooperation and peace as well.

    1. Re:Comments at TFA by Mysticalfruit · · Score: 3, Interesting

      How many miles long? Consider the fact that run way for the shuttle land on is actually 15,000 feet long (4572m)

      --
      Yes Francis, the world has gone crazy.
    2. Re:Comments at TFA by careysub · · Score: 3, Informative

      I did the math. Sufficiently slow acceleration of 3Gs would require a distance of several miles (going from memory here) to achieve 17,000 miles per hour. As much as it sucks, it's still better to put the propulsion system on the vehicle.

      Regards, Jason C. Wells

      It is not possible to put something into orbit using a ground launcher alone. An on-board motor is essential at the very least to circularize the trajectory so that the "orbit" does not intersect the surface of the Earth before completing one revolution. And you lost way to much energy in the lower atmosphere (and create incredible heat loads) trying to ram through it at super-orbital speeds (in fact the G-loading from this deceleration alone will probably be prohibitive for humans).

      For Earth-surface launches it could provide a replacement for the first stage - get you above 95%-99% of the atmosphere where rocket engines are most efficient and no longer have to fight lower atmosphere air resistance. This might make a single (rocket) stage to orbit system practical.

      --
      Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
  6. What's this? by dpilot · · Score: 5, Funny

    Sounds like another government rail subsidy to me. Or is it really "TSA meets Amtrak"?

    (I'm preparing to get strafed.)

    --
    The living have better things to do than to continue hating the dead.
  7. light gas gun by vlm · · Score: 4, Interesting

    I always thought a nuclear steam powered light gas gun filled with electrolyzed hydrogen would be cool. light gas guns never get the love they deserve.

    --
    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    1. Re:light gas gun by EdZ · · Score: 4, Funny

      Maybe they need a sexier name than "nuclear steam powered light gas gun filled with electrolyzed hydrogen".

      I'm not sure you're on the correct website if "nuclear steam powered light gas gun filled with electrolyzed hydrogen" is not near the apex of sexy names.

    2. Re:light gas gun by rahvin112 · · Score: 5, Informative

      The beauty of the railgun and why the Navy is so aggressively pursing them is that explosive based weapons are very dangerous at sea under counter attack. The most secure portion of the ship is often the munitions storage area for this reason as a properly placed round can blow the bottom out of the ship by igniting the munitions stored.

      The railgun does away with the whole bit, the munitions are rods of metal and the propellant is electricity. Without all the powder storage you can either dramatically reduce the size of ship and crew or dramatically increase the number of rounds deliverable before restocking. Finally the restocking ships aren't going to be carrying combustible munitions. A round 1/4 the size of the largest battleship guns fired from a railgun will do nearly 100 times the damage.

      The goal of the Navy DDX program is ships with 1/4 the crew size, 10 times the firepower and a significant reduction in profile (stealth). Imagine being able to field twice the number of ships for half the cost and a single ship has more firepower than 10 current models.

  8. Re:Where's Gordon Freeman when you need him? by somersault · · Score: 4, Insightful

    Pfft. Quake Guy did it first.

    --
    which is totally what she said
  9. Obsoleting their own fleet? by Shivetya · · Score: 3, Insightful

    Truly, if nothing makes a carrier more obsolete is a weapon that can hit one where there will likely be no practical defense. Is any surface ship safe from such a weapon? Yes I know you can definitely pilot an evasive course but you have to know your being attacked before you can do that.

    So how many years before a surface fleet is rendered obsolete? All the quotes in the article about giving sailors more options and precision are too easily reversed.

    --
    * Winners compare their achievements to their goals, losers compare theirs to that of others.
    1. Re:Obsoleting their own fleet? by CrimsonAvenger · · Score: 3, Informative

      Truly, if nothing makes a carrier more obsolete is a weapon that can hit one where there will likely be no practical defense. Is any surface ship safe from such a weapon? Yes I know you can definitely pilot an evasive course but you have to know your being attacked before you can do that.

      Not sure I see how this will make a carrier obsolete, really.

      It's not like a carrier is really worried about 5" shellfire, even at extended ranges - the big missiles with 450+ kg warheads are much more of a problem, really.

      However, as to evading fire from such a weapon. At 200 km, and 2500 m/s muzzle speeds, we're talking pretty near two minutes (yes, it loses speed the whole way, so it won't be anywhere near as quick as 200/2.5 travel time) between shot and landing. And our radars can detect a shell-sized object now (that's what counterbattery radar is for, after all), so you have a minute or more to change your projected position by 200 meters - you can manage that without even turning, just speed up/down as needed.

      This ignoring the detail that you won't even be able to see the carrier at 200 km without aerial surveillance, and the carrier air group will be doing its best to make sure your aerial surveillance quickly becomes sub-surface surveillance....

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    2. Re:Obsoleting their own fleet? by dmgxmichael · · Score: 4, Insightful

      Not sure I see how this will make a carrier obsolete, really.

      It's not like a carrier is really worried about 5" shellfire, even at extended ranges - the big missiles with 450+ kg warheads are much more of a problem, really.

      However, as to evading fire from such a weapon. At 200 km, and 2500 m/s muzzle speeds, we're talking pretty near two minutes (yes, it loses speed the whole way, so it won't be anywhere near as quick as 200/2.5 travel time) between shot and landing. And our radars can detect a shell-sized object now (that's what counterbattery radar is for, after all), so you have a minute or more to change your projected position by 200 meters - you can manage that without even turning, just speed up/down as needed.

      This ignoring the detail that you won't even be able to see the carrier at 200 km without aerial surveillance, and the carrier air group will be doing its best to make sure your aerial surveillance quickly becomes sub-surface surveillance....

      The obsolescence threat to the carrier does not come in the form of a direct threat to the ship's survivability. That is part of it, but not the whole or even the largest of it, and you are ignoring that largest part. What is the carrier's role?

      Projection of Force.

      Carrier aircraft allow it to hit targets up 600 to 1000 km away, or more with refueling tankers. Rail guns however can also hit targets at these ranges, or even further, and even harder.

      And don't kid yourself about being able to dodge the shot either. Not even 2 weeks ago another slashdot article was going on about a steerable bullet that could be fired from a sniper rifle. There is no reason to believe the shells of a rail gun might not also one day be likewise steerable. If we can build a steering system in a 30 gram bullet we can build one in a 5Kg shell. It doesn't take much steering to hit a moving carrier, which can only move 200 meters at most during the entire flight of your bullet.

      And you don't need an explosive in the warhead at all if you have a 2,500 m/s velocity. The kinetic energy from a 5kg slug travelling at that velocity will punch through the hull of a carrier like butter and the impact will be quite explosive without any actual explosive chemicals. After all, F = MV. 2,500 m/s is a LOT of velocity, and you don't need much mass to impart a lot of force on a very small area of the armor to punch through. That's what makes hyper-velocity projectiles so appealing. Their threat is entirely from their velocity - not a dangerous explosive that might go off in storage.

      Anyone who thinks the carrier can survive the appearance of the rail gun on the scene of naval warfare is still fighting the last war, not the next war. The carrier is a big relatively easy to hit target for guns. WWI Battleships can't get close enough to them to sink them because of the planes. A railgun equipped battleship however will be able to not only get in range of the carrier, but outrange the carrier. The shell makes the trip in 2 minutes. That's a long lag time, but nowhere near as much as the hour it takes to launch a plane out to and bomb the attacker. Even if the planes are in the air at the start its still 20 minutes before they can be on site. And yeah, you might shoot down or dodge a rail gun projectile, but what about one every minute? Every 15 seconds? A gun may only have a 1 / 15 minutes firing rate, but multiple ships with these can mass their fire on the large target.

      Carriers are awesome, but so where battleships, so where Ships of the Line. Their days are numbered, and this gun is writing on the wall for them just as surely as the USS Monitor was the writing on the wall for the whole British fleet that fateful day 150 years ago next month at Hampton Roads.

  10. Re:In Mother Russia.... by Nadaka · · Score: 5, Funny

    "When all you have is a railgun, everything starts to look like a smoking crater."

  11. Huh? by assertation · · Score: 4, Funny

    What does it do, shoot Ruby developers off of ships?

    1. Re:Huh? by BitZtream · · Score: 3, Funny

      As a former ruby fan ...

      Finally, something useful to do with Rails developers!

      --
      Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
  12. The future is happening now by assertation · · Score: 4, Interesting

    Ray guns on ships, putty that can heal broken bones in days, robotic military planes, hand held computers.

    I have to say these are interesting times. The "future" ( a sci-fi like world ) is happening right now

  13. Re:WTF submitter?! by Mashiki · · Score: 3, Informative

    Sadly most people these days don't know what Janes is. Probably because most people don't follow either the military or gun culture on /. sad but true. Anyway, I keep wondering whether or not railgun tech will be what brings the battleship back into use. I can see scaled down versions of this on cruisers. But if you want to hammer something down from way off shore and cheaply, I don't think anything else beside a large chunk of floating iron will do.

    --
    Om, nomnomnom...
  14. Re:WTF submitter?! by BisexualPuppy · · Score: 5, Insightful

    Probably because most people don't follow either the military or gun culture on /. sad but true.

    There are so many things I can learn with passion, and killing people is not one of them. Is that sad ?

  15. Re:WTF submitter?! by x0 · · Score: 4, Insightful

    There are so many things I can learn with passion, and killing people is not one of them. Is that sad ?

    What is sad is that you equate gun ownership with killing people. I have quite a few guns, and not once have I threatened anyone. I have, however, made plenty of holes in paper and made steel targets 'ding'.

    How about taking that passion and learning the difference between lawful gun ownership and violent criminal activities.

    I suspect that your passion for leaning stops when your worldview is threatened...

    m

    --
    In the immortal words of Socrates, who said; 'I drank what?'
  16. Re:WTF submitter?! by couchslug · · Score: 5, Insightful

    No. You can delegate it and pretend the world runs on rainbows and unicorns.

    --
    "This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."