US Navy's plane-hurling mass driver in tech hiccup
Software blamed for electro-catapult backfire
Radical plans by the US Navy to equip its next aircraft carrier with electromagnetic mass-drivers for launching aircraft instead of the traditional steam catapults have hit technical snags.
The so-called Electromagnetic Aircraft Launch System, or EMALS, is now under development in a shore-based test facility at Lakehurst naval air station in New Jersey. However, according to reports, the test mass-driver installation suffered serious damage earlier this year in a mishap blamed on a "software malfunction". Apparently the "shuttle" - which moves along the catapult track to accelerate a plane to flying speed - went the wrong way in a test shot and smashed into important equipment.
The Newport News Daily Press, reporting on an interview with EMALS programme chief Captain Randy Mahr, says that the accident has delayed the shore-based testing by several months. It had been planned to commence launching aircraft - as opposed to test loads - this summer, but that will not now happen until autumn.
The next US supercarrier, CVN 78, aka USS Gerald R Ford, is now under construction and intended to join the fleet in 2015. Navy officials confirmed last year that it is now too late to amend the ship's design and revert to steam catapults: EMALS must be made to work or the US Navy will receive the largest and most expensive helicopter carrier ever.
Mahr says that the EMALS mishap won't delay the Ford's arrival, as the hardware is ready for installation on schedule. He is confident that remaining software problems can be rectified after the kit is in place.
"The hardware issues we're comfortable with," he told the Daily Press. "The things that are delaying me right now are software integration issues, which can be fine-tuned after the equipment is installed in the ship."
Mahr had been supposed to hand over the EMALS to another officer and move on to another job by now, following his selection for promotion last year. However, sceptical politicians in Washington, seeking to increase accountability in the event of potentially disastrous failures by the project, have demanded that he remain in post past his normal time.
Present-day catapult carriers, operated only by the US and France, use steam generated by their nuclear propulsion to power their aircraft launchers. The steam catapult was actually a British invention, but the Royal Navy has not had conventional fixed-wing carriers since the 1970s for reasons of cost, instead being limited to more basic ships carrying helicopters and vertical-landing Harrier jumpjets.
Steam catapults are hard on the planes they launch, require a lot of maintenance and manpower, and are bulky and heavy as well. The USN wants to move to EMALS as it should be cheaper to run, less burdensome on the ship and less damaging to aircraft. The electromotive launchers are more flexible and controllable, too, and are expected to be capable of launching lightweight unmanned aircraft as well as new and heavier naval aircraft of the future which steam cats couldn't manage.
EMALS is also of great interest to the Royal Navy, as the new British carriers now under construction will have space in their hulls for catapults to be fitted, though under current plans none will be. At the moment the idea is that HMSs Queen Elizabeth and Prince of Wales will carry F-35B supersonic stealth jumpjets, though it is looking more and more as though the cash-strapped MoD will be unable to afford a suitable number of these complex and expensive planes.
The British ships can't easily be equipped with steam catapults as they are to be gas-turbine powered and so will be unable to generate steam. They could perhaps be upgraded to nuclear propulsion, but this would be costly upfront (though potentially saving money overall in time as cheaper planes could then be bought). With the MoD so short of money this decade, though, this is highly unlikely to happen.
But if EMALS can be made to work reasonably soon, the option would be there for the UK to buy it for the Royal Navy: the Queen Elizabeth class are to have electric transmissions, so they could easily power an EMALS launcher. Britain could then cancel its purchase of expensive F-35B jumpjets.
The carriers could instead be equipped with somewhat cheaper F-35C tailhook stealth planes, or even existing F-18s - much more affordable. It would also be possible to buy existing Hawkeye catapult radarcraft as used by France and America, avoiding the need to custom-develop a pricey vertical-landing radar bird to replace today's ageing AEW Sea Kings.
In fact, the success or failure of EMALS could have a hugely greater effect on the capability of British carriers than on America's. The ability or inability of the Ford to launch jets will a noticeable factor in the US Navy's air punch from 2015 on; but the difference between a future Fleet Air Arm equipped with numerous off-the-shelf aircraft and one with a tiny force of F-35B jumpjets is a lot bigger.
None of that means that the Royal Navy will definitely buy EMALS if it becomes available; but even so, one can be sure that a lot of British naval officers in MoD headquarters are watching the project's progress with interest. ®
...we got the tech sorted Bob. Just one final thing - where are we going to put this highly important , hideously expensive and cutting edge piece of control tech for the mass driver?
Careful with that Bob we've only got the one.
What's that? There's a handy space at the beginning of the mass drivers runway?
That's brilliant it'll be safe there.
This thing does only go one way right?
Intern 1: "Is this function supposed to be cos(-x) or -cos(x)?"
Intern 2: "I think they're the same thing so it doesn't matter."
Shouldn't the headline be :
EMALS suffers from Shuttle Premature Acceleration Mishap