back to article US Navy electromagnetic mass-driver commences tests

A prototype electromagnetic mass-driver, intended to hurl jet aircraft into the sky from the decks of aircraft carriers, has gone into operation at a former airship base in New Jersey. The new kit could be even more important to the Royal Navy than it will be to the US fleet. The EMALS aircraft mass-driver fires a ceremonial …


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  1. Michael Souris

    Mass Driver / Catapult

    "The Moon is a Harsh Mistress" by Robert A Heinelin (ex-US Navy) written in 1966 featured EM Mass Drivers to put payload in orbit. Works better in near-vacuum, of course.

    EM Catapult = Flying Car. Why have I had to wait so long for this?

  2. TrevorPrinn

    Fun toy

    It's nothing more than an oversized Scalectrix set. James May's going to want to build one for the next series.

  3. Dennis 1


    Any chance this can be developed for commercial aircraft.

    Would be awesome to get an A380 aloft and then turn the engines on....

    (less polution/less noise etc etc)

  4. snafu

    Sounds like FUN

    Is that picture available in HiRes somewhere? All those guys and gal look like having great fun.

  5. Daniel Wilkie


    From looking at the picture, it appears to launch people?

    Perhaps a bit like the DARPA People Catapult of yesteryear?

  6. Chimpofdoom!

    Coming soon...

    Launch tubes like they have on BSG...

    Frakkin' toasters will follow...

  7. M7S

    What about the avionics

    Will they require better shielding from all those Gauss fields?

    Just asking.

  8. The Original Ash
    Thumb Up


    Anyone dropped a rare-earth magnet on the rails by mistake?

    Railgun anyone?

  9. James 55

    Alton Towers

    Speak to the guys who designed and built Rita, they seem to have managed to do it.

  10. Neil Stansbury

    Fully Autonomous UAV

  11. Phil the Geek

    Lancashire tech

    Eric Laithwaite will be looking down from the big carrier in the sky with a huge grin on his face!

  12. Herbert Meyer

    launched aircraft will be pilotless

    Already, the limiting factor on acceleration of steam catapults is pilot g's. The limit is about 6g, the pilots have to recover from greyout within a few seconds to fly the plane before it hits the sea. No pilot aboard, higher acceleration.

  13. John Smith 19 Gold badge

    @Dennis 1

    "Any chance this can be developed for commercial aircraft."

    Probably not. This article

    lists a US carrier catapult takeoff as roughly 160mph in 2.5secs. That's about 29ms^-2 or close to 3g. while a lot of people could take 3g for less than 3 secs (modern roller coaster rides can give this, and I imagine some do quite a bit more) it would still likely kill a proportion. And energy requirements scale with mass. The aircraft in the article is 78oooLb (c35 000 Kg). An Airbus would be 10 to 20x that.

    Basically everywhere else other than at sea building a longer runway is a *lot* cheaper and simpler.

    OTOH if you wanted a singel stage to orbit vehicle that could land *and* take off horizontally (looked at by the USAF in the early 90s to the point where Boeing were prepared to offer it as a *fixed* price contract) this would be a very good choice.

  14. TeeCee Gold badge


    Looks like my cunning strategy to make a fortune by cornering the world market in rubber bands is screwed then.

  15. fatchap

    @John Smith 19

    If it was land based presumably you could have a longer run, and so more gradual acceleration.

    This would remove the problem of passengers all passing out on take-off, but would also have the advantage that the aircraft does not need to carry the fuel required to get it up to V2, instead it could be generated by a green technology like a nuclear power plant!

  16. disgruntled yank


    The personnel in the photo appear to be rehearsing a number from Guys and Dolls--what's that about?

    Also, though the US lighter-than-air program had access to helium, and so did not risk gaudy fires such as consumed the Hindenburg, still the Navy's rigid craft did not fare well. As I recall both crashed in bad weather with loss of life.

  17. Daniel B.

    Some good chuckles...

    The steam catapult is a Brit invention ... however, it can't be used in the new Royal Navy's carriers!

    I'm looking forward to seeing this deployed ... and it would also be nice to see something similar used to put stuff into space!

  18. Anonymous Coward
    Anonymous Coward

    Remember Tommy

    At least someone still remembers him.

  19. John Tuffen
    Thumb Up

    @Phil the Geek

    ... My thoughts exactly! I've been showing my children Eric Laithwaites 'The Engineer in Wonderland' recently since they expressed an interest in mag-lev/mag-propulsion (interestingly, my 7 year old son 'invented' mag-lev when he discovered magnetic repulsion, deciding that cars/trains would be much better if they hovered... hence Prof. Laithwaite's book came out!)

  20. John Smith 19 Gold badge

    @Daniel B.

    "I'm looking forward to seeing this deployed ... and it would also be nice to see something similar used to put stuff into space!"

    Depends what you mean.

    EM launch assist is one of several technologies that can help in getting a vehicle started horizontally or (in principle) vertically. This is the time of the vehicle's maximum weight, and is the point when the vehicle burns the most fuel to get the least increase in velocity. Improvements here (if incorporated in the design stage) should give a substantially smaller vehicle, or bigger payload for the same size. Note that it is the *dry* weight that you pay for in design and build. Smaller vehicle gives smaller tanks to make. I think the USAF programme was "Have region."

    Launching a payload to orbit *soley* by EM launch is a mass driver or rail gun approach. This is a very different beast. For a practical size your looking at accelerations in the 100s of g (roughly 321g for a 10km pipe). This is either a high value fast launch system for sensors or weapons or a low price bulk goods launcher. Steering is a problem and you'll need some kind of rocket to fire at orbit to get it onto its orbital track. BTW when the payload exits its tunnel airlock (it's normally presumed to be evacuated) it will be moving at about Mach 23, giving some quite interesting shock wave effects.

  21. SImon Hobson

    Could be interesting for the power system design

    It will be interesting to see what happens to the ships electrical system when they suddenly stick a few megawatts of load on it, and again when they dump those megawatts off it again after the launch. Cue the Bee-Gees - "and the lights all went out ..."

  22. Anonymous Coward

    @SImon Hobson

    Reminds me of Babylon 5, where the Excalibur (?) virtually lost all power after firing their main gun...

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