Plans for construction of the Navy's next-generation destroyer at Bath Iron Works and a Mississippi shipyard remain on track, Pentagon officials said Monday as they sent next year's budget request to Congress. Unlike past years, when the destroyer program and other shipbuilding projects have been targeted for cuts, the fiscal year 2008 budget stays the course for the sleek new ships. The budget requests $3.5 billion to complete construction of the two lead Elmo Zumwalt class destroyers, with one to be built at BIW and the other at Northrop Grumman Ship Systems in Pascagoula, Miss. After the lead ships are built, the two shipyards are expected to compete for future contracts. The Navy plans to contract for one destroyer each in 2009, 2010 and 2011, for a total of five ships.