The Navy and its industry team for the first Flight III variant of the Arleigh Burke-class DDG 51 destroyers completed a major milestone of integrating an advanced radar and the Aegis combat system on the ship well ahead of schedule to ensure everything works as intended, an official with shipbuilder Huntington Ingalls Industries [HII] said this week.

Aegis Light Off (ALO) on the future USS Jack H. Lucas (DDG 125) was completed in December, about 12 weeks ahead of schedule, and is “the critical milestone to support the beginning of combat testing” that will ultimately lead to builder’s trials, George Nungesser, vice president of program management at HII’s Ingalls Shipbuilding division, said on Wednesday to reporters during a virtual media briefing as part of the annual Surface Navy Association National Symposium.

The Navy announced the ALO milestone on Monday.

The primary change from the current DDG 51 Flight IIA destroyers to the Flight III ships is the move to Raytheon Technologies’ [RTX] SPY-6(V) air and missile defense radar, which required significant changes to the power and cooling requirements housed on the ship, Nungesser said. For example, the air conditioning plant on the Flight III vessels is 300 tons versus 200 tons on the Flight IIA ships, he said.

The DDG 51 Flight IIA ships operate with the Lockheed Martin [LMT] SPY-1D radar.

The SPY-6(V) integrates with the Aegis combat system supplied by Lockheed Martin.

Nungesser said that contractually, to achieve ALO, Ingalls had to demonstrate to the customer that all the systems such as power, air, water, and cooling are hooked up to support the combat systems testing.

To manage risk and maintain the program schedule, which remains on track, Nungesser said that two to three years ago the Navy and industry partners put together integrated product teams at different levels of program oversight and execution.

“Just the transparency of getting all the risk on the table actually gets you to a much quicker place in support of trying to make the schedule,” he said. “That was one of the turning points on this.”

Key milestones in the coming months with DDG-125 include fueling the ship, which will occur in February, which will allow for the generators and main engines to be turned on, Nungesser said. These will be first half of 2022 events, he said.

The Flight III ship also has a water mist fire-fighting system instead of a Halon system used on the Flight IIA ships, Nungesser said. The water mist testing began recently, he said.

Huntington Ingalls has four Flight III DDG 51s under construction and Nungesser said the lessons being learned with the Jack H. Lucas are being applied to the follow-on ships to reduce schedules.