The Lyndon B. Johnson, the third Zumwalt-class guided missile destroyer, is seen during a christening ceremony at Bath Iron Works, Saturday, April 27, 2019, in Bath, Maine. Credit: Robert F. Bukaty | AP

BATH, Maine — A new report by the Government Accountability Office criticizes the U.S. Navy and Bath Iron Works for more than 320 “serious deficiencies” found upon inspection when the shipyard delivered the first-in class USS Zumwalt’s hull, mechanical and electrical systems in May 2016.

Another 246 “serious deficiencies” were found after acceptance trials in January and February 2018 for the USS Michael Monsoor, the second of three “stealth” destroyers built in Maine.

The deficiencies “increase the likelihood that the ship will not be fully capable and sustainable when provided to the fleet,” according to the Weapon Systems Annual Assessment report issued this month to Congress.

Among the GAO concerns are that BIW’s delivery of hull, mechanical and electrical systems for all three ships in the class are 18 months behind schedule, a delay due in part to problems completing electrical work associated with the ship’s power system.

The report is critical of the failure by the Navy and BIW to stabilize the DDG 1000 [the USS Zumwalt] design by 2009, when the lead ship fabrication began — “an approach inconsistent with best practices,” the report states.

“The shipbuilder also experienced problems completing the power system for DDG 1001 [the USS Michael Monsoor],” the report states. “Following sea trials, the Navy inspected one of the ship’s main turbine generators and found that the generator was damaged by a woodscrew. The damage was extensive enough that the Navy chose to replace the engine and send it for repair.”

Jay Korman, a Navy analyst and managing director at Washington, D.C.-based consulting firm Avascent, said Thursday that while the GAO serves an important function, its annual assessment typically “doesn’t carry a lot of weight,” because, in this case, the three-ship class of destroyers is nearly complete.

But the report’s criticism about the core mission of the ship is far more concerning, he said.

The report cites “numerous design changes after the fabrication start and significant cost increases and schedule delays.”

“Nearly 10 years later, development and shipboard testing of technologies continues, each of which could lead to discovery that could disrupt the design stability the Navy currently claims,” the report states.

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The report also faults the Navy for delays due to changing the mission of the Zumwalt destroyers from land-attack to surface warfare, which will require the ships to be fitted with additional missiles and other systems — changes which will cost about $1 billion, according to the report.

Also a concern is the lack of a suitable projectile for the destroyers. The Navy initially planned to use the Long-Range Land Attack Projectile (LRLAP), but determined that the high cost —- $800,000 to $1 million per round — was prohibitive.

After evaluating five other munition options, the Navy found no viable replacement, according to the report. “As a result, the guns will remain inoperable on the ships for the foreseeable future,” the report states.

Criticism that the Navy is just now addressing weapons that aren’t satisfactory “is somewhat problematic,” Korman said. “That speaks to the core mission of the ship. It doesn’t look good when Navy officials are in the process of determining operational concepts after the ship has been built.”

But Loren Thompson of the nonprofit Lexington Institute said many of the criticisms levied by the GAO were not aimed at BIW.

“First, it isn’t BIW’s fault that the Navy failed to procure a suitable munition for the main guns,” Thompson wrote in an email. “Second, it isn’t BIW’s fault the Navy changed the mission for the vessels. Third, while BIW may be responsible for various construction deficiencies, those are common on the lead ship of a new class, and Zumwalt is a radical departure from traditional warship design.”

“The reality is that [Zumwalt class] destroyers have made steady progress, and very few shipyards around the world could have done as good a job as BIW has,” Thompson said.

According to the report, the first-in-class USS Zumwalt is scheduled for final delivery in September 2019, with the second destroyer, the USS Michael Monsoor, due for final delivery in September 2020.

To minimize further delays to the first two ships, the Navy has authorized BIW to take parts from the third ship, the future USS Lyndon B. Johnson — which is now 84 percent complete — but as a result the delivery date of that third ship is unclear. The Navy has tentatively scheduled final delivery of the third destroyer for September 2022.

Overall, however, the report finds progress of the program “has been steady if occasionally delayed,” with the USS Zumwalt embarking on its first “operational period at sea” in March 2019; the USS Michael Monsoor was commissioned in January 2019; and the future USS Lyndon B. Johnson was christened last month.

Bath Iron Works on Thursday declined to comment on the GAO report. The Navy did not immediately respond to a request for comment.