WASHINGTON — Shipbuilder General Dynamics Bath Iron Works formally delivered the stealth destroyer Zumwalt (DDG 1000) to the US Navy Friday, marking a turnover of ownership from the ship's status as a private vessel to become a government-owned warship.

"Today represents a significant achievement for not only the DDG 1000 program and shipbuilding team but for the entire US Navy," Capt. Jim Downey, the Zumwalt-class program manager at Naval Sea Systems Command, said in a statement. "This impressive ship incorporates a new design alongside the integration of sophisticated new technologies that will lead the Navy into the next generation of capabilities."

Delivery represents a major milestone in the design and development of the ships, conceived in the late 1990s as the epitome of stealth in warship design. At various times the Navy envisioned 32 ships in the class, then 28, then seven, then two, and back up to three – the class size of today.

Concept and design work has been taking place on the Zumwalt class since the late 1990s, when it was known as the Land Attack Destroyer variant of the Surface Combatant 21 (SC 21) program.  It was known as the DD(X) program in 2002 when Northrop Grumman and Raytheon were chosen as the prime contractors, and recast as the DDG 1000 in April 2006.

For a variety of reasons prime contractor responsibility shifted to the Navy, with General Dynamics Bath Iron Works overseeing the hull, mechanical and engineering (HM&E) portion of the shipbuilding contract. Raytheon retains overall responsibility for the combat system.

A construction contract was awarded for the Zumwalt in Feb. 2008, when the ship was expected to be delivered in July 2014. A keel-laying ceremony was held in November 2011 at Bath's Maine shipyard, and the destroyer was launched in October 2013.

The Zumwalt first went to sea in December 2015 for Alpha trials, a series of tests run by the shipbuilder to test the ship's HM&E components. A second Bravo trial was held in March, and the Navy's Board of Inspection and Survey (INSURV) completed out a two-day acceptance trial on April 21.

With delivery, the Zumwalt's Navy crew has officially moved aboard and taken up residence. She's expected to sail away from Bath this fall and will likely operate for a few weeks from the fleet base at Norfolk, Va., travelling to Baltimore, Md., for an October 15 commissioning ceremony. After that, the Zumwalt will leave the US East Coast for her homeport of San Diego.

Work on the Zumwalt is by no means finished. A new phase will begin in 2017 as Raytheon and the Navy work to complete the ship's combat systems – an array of radars, sensors and weapons. By late 2017 or the first part of 2018, the Zumwalt should be ready for combat system operational testing (CSQT), when the weapons and sensors will be fully tested. Only after the successful completion of CSQT will the Zumwalt work up for a deployment.

Two more Zumwalt-class ships, the Michael Monsoor (DDG 1001) and Lyndon B. Johnson (DDG 1002), are under construction at Bath.