Watch the US Navy Test Its Electromagnetic Jet Fighter Catapult

An anonymous reader sends word via Engadget that the U.S. Navy has tested its Electromagnetic Aircraft Launch System for the first time with a "dead-load" (a wheeled steel sled that weighs as much as a jet) aboard the Gerald R. Ford carrier. The article goes on to say: "Its advantages over traditional catapults that use steam instead of electromagnetic energy include smoother acceleration and its ability to place less stress on the aircraft — plus, it was designed to work even with more advanced carriers that the military will surely use in the future." You can watch a video of the "dead-load" testing here.

Comments

intuitively I would think steam would be better

[goombah99]

Steam seems like an ideal solution to me. Steam expands so well the dynamic range of it's force curve seems apropos to the task. How much of the EM energy goes into force? surge currents and magneto striction are usually things people find shorten the lifetime of electo devices yet here they are at the extreme in these. Presumably there's no shortage of steam available and it's a great way to store energy.

Re:intuitively I would think steam would be better

[TooMuchToDo]

Yes to both!

Using a linear motor instead of a steam catapult allows you to configure specific power during any point of the process. goombah99 mentions there's no shortage of steam, but newer carriers are moving away from needing steam to be generated, preferring to take power directly from their generators to the linear motors up top.

Could this be used for civilian airports? Most definitely! Its most likely cost prohibitive though, so unless you're someone leaving a major hub always near takeoff max weight (UPS/Fedex possibly?) or you're at an airport that has a very short runway or a very high altitude runway (both due to geography), it doesn't make sense financially.

Re:I don't get the point of this thing...

[Deadstick]

The carriers are all nuclear which means they boil sea water to turn steam turbines.

No. Only a very modest amount of seawater gets boiled in a distillation plant heated by the reactor; the resulting freshwater goes into the propulsion engines, which are closed Rankine cycles. Water goes round and round from boiler to turbines, to a seawater-cooled condenser that turns it back into liquid, to the boiler again. Lather, rinse, repeat. If you tried to use seawater in the propulsion plant, it would fill up with salt in a matter of hours. The distillation plant only supplies enough water to the engines to replenish what leaks out; the rest of its output goes to the catapult system.

The EM system means you have high voltage lines running under the decks

Ever been in the same space with a battle-damaged steam line?

such big industrial machines are hydraulic in most cases. They rely on pressure

Steam machines rely on pressure times volume, which is an order of magnitude increase in control problems.

how much longer will jet fighters be relevant?

[cas2000]

when nations or even non-state groups can put up swarms of, say, 1000 drones for $1M. or 10,000 drones for $10M.

aside from the economics (using $1M+ missiles to shoot down $1000 drones) can a jet fighter even cope with swarms of cheap drones ramming its jet intakes, with or without small explosive charges?

can jet fighters even shoot other targets if there's a huge swarm of drones in the way, programmed to intercept missiles and blow them up before they hit?

and as they get smaller, can a jet and/or its pilot even detect a single drone reliably if its disguised as a bird? a bird with a payload of quarter to half a kilo of C4 to be delivered to the jet engine?