A one-of-a-kind SEAL mini-sub based at Pearl City Peninsula that has been plagued by years of development problems and cost overruns won't be repaired after a November fire because the work would cost $237 million and take nearly three years, U.S. Special Operations Command said yesterday.

The decision could be a final blow to a program that once envisioned a fleet of the 65-foot mini subs, designed to ride piggyback on much larger attack submarines and deliver SEALs dry and rested to an insertion point.

The Advanced SEAL Delivery System, or ASDS, originally was expected to cost about $80 million per sub. But the Northrop Grumman program spiraled to more than $885 million, with only one sub built, according to a 2007 U.S. Government Accountability Office report. Delivery of ASDS-1 was accepted in 2003.

One of Special Operations Command's biggest investments was beset by battery, noise and propulsion problems, and in April 2006, the Defense Department canceled plans for follow-on ASDS boats and directed the Navy and Special Operations Command to set up an ASDS-1 improvement program.

The $237 million repair estimate from the Nov. 9 fire is $180 million more than the entire budget for the ASDS program, according to Special Operations Command, based at MacDill Air Force Base in Florida.

The command said "competing funding priorities" for current and projected special operations budgets prevent it from repairing ASDS-1.

The fire broke out while the submersible's batteries were recharging at its Pearl City home port. The 8:30 p.m. fire occurred during routine maintenance, which included the battery recharging, the Navy said in a news release.

The fire damaged the ASDS' operations compartment, which affected all the boat's operating systems, Special Operations Command said.

The battery system, sonar, motors and controllers, anchor assembly and hull were also damaged.

The "root cause analysis" — being done to determine the fire's origin — is not complete, the command said.

NEW SUB EMERGING

Lt. Cmdr. Fred Kuebler, a Special Operations Command spokesman, yesterday said the final disposition of ASDS-1 has not been determined. He did not rule out the possibility of repair.

Kuebler had no information about possible manning changes at the Pearl City facility.

The command also has requested funding for the Joint Multi-Mission Submersible program to develop an alternative SEAL insertion craft.

The online publication Inside the Navy reported in June that $43.4 million was being sought for pre-design work on the mini-sub that would provide "improved performance" over the ASDS.

The ASDS was heralded as a "transformational leap ahead" design and was intended to deliver commandos dry and rested to a point of departure. The current SEAL Delivery Vehicles are open to bone-chilling cold water and require the use of scuba gear.

BIG PLANS FALTERED

Designed to ride piggyback on the Los Angeles-class submarines Greeneville and Charlotte, both based at Pearl Harbor, as well as on new Virginia-class submarines and former ballistic missile subs converted to carry conventional missiles and commandos, the boxy, 8-foot-diameter ASDS was designed to sneak up close to shore with two crew and up to 16 SEALs.

Its skin is the material used on stealth fighters, it could take and transmit pictures almost in real time, and its design allowed for long-range operations.

The Navy in 2004 celebrated the completion of a $47 million waterfront home for SEAL Delivery Vehicle Team 1 on 22 acres at Pearl City Peninsula that included a 326,000-gallon freshwater test tank.

At the time, the team had 45 officers and 230 enlisted personnel — 93 of them SEALs.

The GAO said in 2007 that the ASDS had "encountered a difficult, long and costly development since the initial contract was awarded in 1994."

Despite those problems, the Navy in July 2003 took delivery of the first ASDS.

The craft rode piggyback on the submarine Greeneville during a deployment to the Persian Gulf by Expeditionary Strike Group 1.

The ASDS was supposed to deploy with the USS Michigan, a former ballistic missile submarine converted to carry conventional missiles and commandos, shortly after the fire.

The entire program, including six mini-subs and facilities in Hawai'i and Little Creek, Va., originally was to cost $527 million.