At Lakehurst Naval Engineering Center.
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The steam catapults are capable of launching up to 90,000 pounds and producing speeds up to 185 knots under normal conditions and up to 300 knots for special catapult tests. Used primarily to test catapult performance before actual aircraft launching, they offer a unique deadload launch capability for a programmed linear acceleration that allows testing of drop tanks, cargo tie- downs, and pylons.
http://www.defenseindustrydaily.com/EMALS-Electro-Magnetic-Launch-for-Carriers-05220/
http://www.engadget.com/2010/12/21/us-navys-electromagnetic-aircraft-launch-system-launches-first/