The San Antonio Express-News gives us the conclusion of weeks of repairs in Bahrain for the USS San Antonio.

The USS San Antonio, docked in Bahrain the past several weeks for repairs to a leaky engine oil lubrication system, left port Tuesday and prepared to rejoin its strike force in the Persian Gulf.

The Navy said that poor welds and joints that lacked support caused the leaks, which sprang up during the ship’s maiden voyage this fall.

But spokeswoman Pat Dolan said the Navy team that spent 25 days making the repairs still had not determined who was responsible for the sub-par construction: the service or Northrop Grumman Ship Systems. It also isn’t clear if three other San Antonio-class ships in the fleet have the same problems.

“They’re just returning from Bahrain,” she said of the repair team, “so we don’t have the root-cause analysis complete yet.”

The San Antonio will rejoin the USS Iwo Jima expeditionary strike force, now in the Navy’s 5th Fleet area of operations. As the ship continues its mission, the Navy will press its investigation into the cause of the leaks as well as learn if there are problems with oil lubrication systems aboard the USS New Orleans, USS Mesa Verde and USS Green Bay.

Dolan said the Navy hopes to have the analysis of those ships finished by mid-December.

Troubled by design flaws, construction delays and a failed inspection last year, the San Antonio entered the fleet well behind schedule, its $1.8 billion price tag three times the original estimate. The San Antonio left the East Coast for the Persian Gulf at the end of August but put into port in Bahrain last month when the crew discovered the leaks.

A special 40-member team that included pipe fitters, inspector and engineers was flown to Bahrain and spent more than three weeks analyzing and repairing the oil lubrication system.

Dolan said the team repaired the systems for two of the ship’s four engines in the forward and aft main machinery rooms of the San Antonio. She said she was unaware of any other problems with the ship.

Inspectors found an inadequate number of hangers to support lubrication pipes that feed oil into the engines, Dolan said. The lack of hangers, coupled with vibration throughout the ship, caused some of the welded joints to come loose, she said.

“The failures can be attributed to inadequate piping support, poor welding, material selection and insufficient quality assurance,” she said. “They ended up putting in additional pipe support, going in and taking out in some cases whole sections of pipes and joints. I can’t tell you the blow-by-blow, what they did or repairs. I can tell you that’s in general what they did.”

It’s good that a root cause analysis is being performed, but this analysis should include fully independent engineers, contracted from a pool of engineers not associated with defense contractors. The team should include experts in welding, fracture mechanics, mechanical and vibration engineering, and fluid flow and corrosion (chemical) engineers.

Furthermore, the analysis shouldn’t stop with a technical analysis, but should include the whole management and decision chain that led to the circumstances we face with the USS San Antonio, such as the use of Management Oversight and Risk Tree analysis. The problems listed above must be categorized into root and contributing causes and a full open source report issued on the management and engineering failures, along with recommended corrective actions.

Prior and other resources:

Time, The Navy’s Floating Fiasco.

The Captain’s Journal, The 26th MEU Stuck at Bahrain.

The Captain’s Journal, The 26th MEU, The USS San Antonio, and Military Equipment.