The modification fully funds construction of the first two ships of the new ship class. Construction of the first vessel will begin immediately, with delivery by the spring of 2013, the company said.
The contract includes an option for the construction of a third MLP which, if exercised, will increase the contract value to about $1.3 billion.
"With the Mobile Landing Platform Program, NASSCO will continue our tradition of building high-quality ships for the U.S. Navy," said Fred Harris, president of General Dynamics NASSCO. "The first MLP ship will start production with more design, engineering and planning work complete than any ship that NASSCO has constructed since World War II."
The Mobile Landing Platform is a new class of auxiliary ship for the Navy. Once delivered to the fleet, these ships will join the three Maritime Prepositioning Force squadrons, which are strategically located around the world to enable rapid response in a crisis.
The company said the new ships will change the way the Maritime Prepositioning Force operates. MLPs will provide a "pier at sea" that will become the core of the Navy and U.S. Marine Corps sea-basing concept to allow prepositioning ships -- like LMSR's and T-AKE's -- to offload equipment and supplies to the MLP for transshipment to shore by LCACs or other vessels.
MLP ships will be 765 feet in length and 164 feet in beam, with a design draft of 29 feet. The deadweight tonnage is in excess of 60,000 metric tons.
General Dynamics NASSCO said the contract will significantly reduce the number of employees affected by a previously announced potential layoff notice.