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Navy Uses Railgun To Launch Fighter Jet
Phoghat writes "In 2015 the aircraft carrier USS Gerald R. Ford will take to the seas and the plan is to use a railgun to launch planes, instead of steam powered catapults. From the article: 'The Navy developed its Electromagnetic Aircraft Launch System as a replacement for the steam catapults currently used on aircraft carriers. The EMALS is a linear induction motor that's capable of accelerating a 100,000 pound aircraft to 240 miles per hour in the space of 300 feet. Compared to a steam catapult, the railgun catapult is much smaller, more efficient, simpler to maintain, gentler on airframes, and can deliver up to 30% more power. It's also capable of being cranked down a whole bunch, meaning that it can also launch smaller (and more fragile) unmanned drones.'"
I would guess it's easier on the airframe because it can have a different acceleration curve. I imagine a steam driven catapult as having high power at the onset, but lower power at the end, while an electronic method like this can have a more gradual push.
The maximun launch weight on pure ski-jump systems are much much lower than catapult launches. The old British carriers for example were stuck launching Sea Harriers which had a max take off weight of 12000kg. The F-18 (the original one... they've all been replaced by heavier planes) had an EMPTY weight just 1000kg less than that. It's max take off weight from a US Carrier was almost over twice that of the Sea Harrier.
The new British carriers (suppose to launch Eurofighter variant) will also have a catapult.
The catapult is another point of failure. That's one reason there's 4 on a ship. And that's reason why US had an advantage. They had an unbroken string of experience designing, building, and maintaining catapult systems since the end of WW2.