The delivery of the Navy's $8 billion Zumwalt destroyer has been delayed again, putting it years behind schedule

• The delivery of the US Navy's $7.8 billion USS Zumwalt (DDG-1000) destroyer has been delayed again, pushing its final delivery back from last month to the second quarter of fiscal year 2020, NAVSEA told Business Insider, confirming a Bloomberg report.
• The Zumwalt, a first-in-class destroyer that has been something of a problem child, is now years behind schedule.
• The Zumwalt has faced challenges with design stability, weapons systems, ammunition, and mission, among other issues.
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The delivery of the US Navy's $7.8 billion USS Zumwalt (DDG-1000) destroyer has been pushed back again, putting the first-in-class ship years behind schedule.

"Final delivery of DDG 1000 is planned for the second quarter of Fiscal Year 2020," a Naval Sea Systems Command (NAVSEA) spokeswoman told Insider, confirming an earlier Bloomberg report on the delay. Final delivery of the Zumwalt with full combat capability was initially expected in September.

NAVSEA said that the Zumwalt "has been conducting combat system testing concurrently with post-delivery test and trials," adding that "while combat system testing has made significant progress, Zumwalt continues to work through first-in-class integration and shipboard test challenges."

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The latest delivery delay, Bloomberg reports, puts final delivery six years behind schedule, and while NAVSEA says that plans for the ship to achieve initial operating capability (IOC) in September 2021 remain on track, that will still be three years later than first expected.

The Zumwalt is a multimission surface ship that, like the USS Gerald R. Ford and the Littoral Combat Ship, has long been a bit of a problem child for the Navy.

The Navy had initially planned to build 32 Zumwalt-class destroyers, but the number has since been reduced to three. The ships were expected to be tasked with carrying out naval surface fire support missions in littoral waterways, using 155 mm Advanced Gun Systems (AGSs) specifically designed for the task by BAE Systems.

When the Navy realized the prospective cost of a single AGS Long-Range Land-Attack Projectile (LRLAP) had risen to at least $800,000, a byproduct of ordering fewer ships, it went in search of a cheaper alternative, which it has yet to find.

The AGS is now useless, and there is talk of totally scrapping the guns, on which the Navy spent about a half-billion dollars.

Read more: The destroyer Zumwalt's big guns don't have any ammo, and the Navy may ditch them entirely because they don't even work right

The Zumwalt's warfighting mission, given its gun problems, has since changed from naval surface fire support, a mission consistent with the battleships of naval warfare decades earlier, to surface strike, targeting enemy ships and some land targets with missiles.

It's possible the AGS may be replaced with more Vertical Launch System tubes, if not another weapon system. This mission set is still being evaluated.

The Government Accountability Office (GAO) explained in May, when the Zumwalt was first expected to be handed over to the Navy before the delivery schedule was revised to September, that the service is still trying to correct the more than 300 deficiencies identified when the Navy first accepted the ship from General Dynamics in May 2016.