Groton — Submarines may not go to sea on time if the federal employees who were furloughed because of the government shutdown do not return to work soon, according to the Navy.

The military and civilian employees who work at the Supervisor of Shipbuilding, Conversion and Repair office — also known as SUPSHIP — in Groton are involved in every aspect of submarine construction, repair, maintenance and modernization as the liaisons between the Navy and Electric Boat.

Of the 250 employees, about 230 are civilians. Most of them, about 217 people, were furloughed Tuesday after Congress failed to reach an agreement on continuing to fund the government.

United Technologies Corp., which is based in Hartford, plans to halt some of its defense manufacturing work because government inspectors were furloughed. The company said it will furlough about 2,000 of its Sikorsky Aircraft Corp. employees beginning Monday and a total of more than 5,000 if the shutdown continues into next month.

U.S. Rep. Joe Courtney, D-2nd District, said the shutdown would have to "drag on for a significant amount of time" before Electric Boat encounters the same issues as UTC, since the military orders far more helicopters than it does submarines.

"Because of the volume and frequency of helicopter production, the impact of the loss of inspectors is being felt a lot faster," Courtney said.

The Republican-controlled House of Representatives passed a continuing resolution to extend the current spending rates for six weeks but also to delay the Affordable Care Act, which Senate leaders said they would not do.

The furloughs also impact the on-site government contract administration at SUPSHIP, which includes quality oversight, technical concurrence and fiduciary functions, according to Chris Johnson, a spokesman for the Naval Sea Systems Command.

The office cannot certify EB's work for submarines currently under construction or for those in the shipyard for maintenance, Johnson said. Key events and construction milestones are not being delayed at this time, he said, but if the furloughs continue, the impact will become more severe and potentially could limit the ability of submarines to get underway.

Johnson said he could not yet say when that would happen.

Robert Hamilton, spokesman at Electric Boat, said he could only say that a short shutdown is not expected to significantly impact operations.

EB is getting ready to christen a new Virginia-class submarine, the North Dakota, on Nov. 2. The USS Mississippi is in the yard for maintenance, repairs, alterations and testing as part of its post-shakedown availability. EB is also performing maintenance and modernization work on two Los Angeles-class submarines, the USS Toledo and the USS Hartford.

SUPSHIP employees are responsible for ensuring the efficiency and quality of the ships constructed and maintained by the industrial base. They enforce the design standards and contract requirements, and oversee the construction process. The military personnel in the Groton office can perform some of these functions while the civilians are furloughed.

The civilian employees also were furloughed after the automatic budget cuts known as sequestration took effect, and most salaries for federal employees have been frozen for three years.

Courtney said the Pentagon and White House soon will determine whether the Pay Our Military Act could be broadly interpreted to bring furloughed civilians back to work. The act ensures that members of the military and some Defense Department civilians continue to receive paychecks during the shutdown.

There is growing support within the Republican Party for passing a continuing resolution to resume government operations without addressing the Affordable Care Act. Courtney said he thinks EB should be able to manage for at least a week or two.

"It's hard for me to fathom that we can't have this thing resolved by then, given the momentum that is starting to build up by Republicans to support a measure the president will sign," he said. "... So hopefully this will be a moot point as far as EB and submarine construction is concerned."

j.mcdermott@theday.com