[Updated with new information from the Navy] After we posted our article on the electrical problem that left the USS Freedom “briefly” unable to navigate, the Navy provided us this detailed official explanation from Lt. Cdr. Clay Doss:

USS Freedom (LCS 1) returned to Changi Naval Base July 21 after experiencing a problem with the ship’s electrical plant that caused a temporary loss of propulsion the previous morning. Freedom restored propulsion and returned to port under her own power to accomplish repairs with available spare parts. At no time was the ship or crew in danger. The crew is now working with maintenance technicians in Singapore to accomplish repairs.

Freedom departed Changi Naval Base July 19 to participate in the at-sea phase of CARAT Singapore, which begins July 21 and continues through July 25. The ship lost propulsion briefly July 20 while making preparations for a vertical replenishment in support of CARAT Singapore. Freedom never lost power, the crew restored propulsion, and the ship completed the vertical replenishment.

Initial assessment on the loss of propulsion is that the NR2 Ship Service Diesel Generator (SSDG) overheated and shut down. The crew determined a turbocharger in NR2 SSDG had an exhaust leak and needs to be replaced. Turbochargers increase SSDG efficiency and power by forcing more air into the combustion chamber.

Freedom also experienced problems load shedding between online generators that will require further troubleshooting by maintenance technicians in Singapore.

Freedom’s commanding officer decided to return to port to accomplish repairs with available spare parts, and to allow the crew and maintenance technicians to continue troubleshooting the electrical plant as required.

While it is general policy not to discuss specific maintenance timelines or operational schedules, technicians are working quickly to repair the problem. If repairs are accomplished soon, Freedom will return to sea and join other U.S. Navy units in Combined Task Group 73.1 along with Republic of Singapore Navy ships to participate in the sea phase of CARAT Singapore.

The Navy deployed Freedom to Southeast Asia to work with regional navies and to put the ship through its paces in littoral waters several thousand miles away from homeport in San Diego. Despite challenges that are not uncommon for any U.S. Navy ship on deployment, let alone a ship that has never deployed overseas before, the Freedom crew continues to perform well as they capture valuable lessons learned that will inform follow-on rotational deployments as well as the LCS program.

Located in Singapore, the Navy’s Commander, Logistics Group Western Pacific (CLWP) has extensive experience providing maintenance and logistics support to 7th Fleet units deployed in South and Southeast Asia. As Freedom is a first-of-class ship on a maiden deployment to Southeast Asia, the Navy expected supporting an LCS would require flexible and innovative approaches. We are confident that the right combination of technical assistance and logistics support are in theater now to address this issue.

[Updated] At 2:00 pm Wednesday, the Navy issued a second statement saying that Freedom was back underway:

-USS Freedom got underway to resume participation in the at-sea phase of Cooperation Afloat Readiness and Training (CARAT) Singapore the afternoon of July 24 after accomplishing repairs to the ships electrical plant.  Freedom will join USS Fitzgerald (DDG 62), USNS Washington Chambers (T-AKE 14), a U.S. Navy P-3 aircraft and several Republic of Singapore Navy (RSN) ships in the most complex scenario of the exercise, featuring combined training in surface warfare, air defense and anti-submarine warfare.

-Initial assessment on the loss of propulsion was that the NR2 and NR3 SSDGs overheated and shut down.  Since arriving in Singapore July 21, the crew and maintenance technicians replaced turbochargers in NR2 and NR3 ship service diesel generators (SSDG).  Fuel oil delivery system components that also contributed to overheating and shutdown were replaced as well.  For example, the crew replaced worn fuel oil couplings, clogged fuel injectors and temperature sensors.