President Donald Trump is scheduled to preside over the commissioning this week of the Navy’s newest aircraft carrier, the Gerald R. Ford, even though it won’t be ready for its first combat deployment for at least four years, according to congressional auditors.

The $12.9 billion carrier, designated CVN-78, was delivered in May “with a significant amount of outstanding construction, tests” and sea trials, the Government Accountability Office said in a new report that examined shortcomings in the Navy’s processes for ensuring quality and accepting finished ships.

While the the Ford was delivered 32 months later than originally planned, the Navy probably will still need to spend as much as $780 million to finish deferred work, correct deficiencies and conduct Pentagon-mandated shock tests and other outfitting, the GAO found.

The Navy has announced that Trump will come to the commissioning of the nuclear-powered carrier at Norfolk Naval Station in Virginia on Saturday. It will be Trump’s second event promoting the long-planned ship as a centerpiece of his pledge to expand the Navy’s fleet to 350 ships from the 276 that can be deployed today.

‘Navy We Need’

On a visit in March to Newport News, Virginia, Trump exulted that the Ford’s vast deck feels “like you’re standing on a very big piece of land.” He also promised to provide the “twelve-carrier Navy we need.” Ten carriers are in service today. Two more ships in the Ford class, the John F. Kennedy and Enterprise, are also expected.

The GAO said delays and a cost increase of as much as 22 percent since 2010 for construction led the Navy to accept delivery of the Ford “with a substantial amount of incomplete work.”

The agency said the ship built by Huntington Ingalls Industries Inc. has “yet to complete its navigation certification and cybersecurity inspection,” nor does it have all the certifications necessary “to conduct aviation operations, among other things” GAO said.

In addition, the carrier hasn’t yet been cleared to launch fighters carrying extra fuel in wing tanks because of software issues with the new electromagnetic catapult system that cause excessive stresses at launch, Bloomberg News reported last month.

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Beyond the Ford’s unfinished business, the GAO report casts doubt on the certification and inspection processes the Navy will employ to deliver vessels as its fleet expands. A Navy spokeswoman didn’t respond to questions about the report.

“Shipbuilding is a complex endeavor, and a certain amount of deficiencies can be expected,” but “all of the Navy ships we reviewed were, or likely will be, provided to the fleet with outstanding deficiencies, incomplete certifications, or open casualty reports, among other quality issues — resulting in additional costs that the fleet will have to bear,” GAO said.

“The Navy has made liberal use of the various exceptions to its process for some of its most expensive and technologically sophisticated ships,” including the Ford, that permit them to be delivered “in a substantially incomplete state,” the GAO said.

The eight vessels reviewed in the report included two early Littoral Combat Ships, the new DDG-1000 destroyer and the USS Mississippi, which is a Virginia-class submarine.

The report was issued as the House last week passed a $696 billion defense policy bill that authorized five more vessels than the Navy requested. The bill would authorize three of the broadly criticized Littoral Combat Ships, one more than requested.