On Saturday, December 18, 2010, The Electromagnetic Aircraft Launch System, or EMALS successfully launched a F/A-18E Super Hornet. It is the first time in history a railgun has launched a jet. Railguns are better than the steam powered catapults currently in use for many reasons. The Navy has been experimenting with them for use as guns and jet launchers because they have no moving parts. They are smaller and more efficient than the current catapults.
They also launch the jet smoother and more efficiently. They are expected, according to the Navy press release, to be more versatile than current catapults for they could simply give the device more or less power and be able to launch a wider variety of craft.
They are expected to be operational on carriers by 2015.