WASHINGTON — Despite years of development, constant effort and numerous official pronouncements of progress, the minehunting system at the heart of a new family of US Navy mine countermeasures gear shows no signs of improvement and poses a significant risk to the planned deployment of the system aboard littoral combat ships (LCS), according to the Pentagon's top test and evaluation officer.

"Recent developmental testing provides no statistical evidence that the system is demonstrating improved reliability, and instead indicates that reliability plateaued nearly a decade ago," Michael Gilmore, director of the Office of Test and Evaluation (DOT&E), wrote in an Aug. 3 memo to Pentagon acquisition chief Frank Kendall.

A copy of the memo was obtained by Defense News.

"The reliability of existing systems is so poor that it poses a significant risk to both the upcoming operational test of the LCS Independence-variant equipped with the first increment of the Mine Countermeasures (MCM) mission package, and to the Navy's plan to field and sustain a viable LCS-based minehunting and mine clearance capability prior to fiscal year 2020," Gilmore wrote.

The mission package is called the remote minehunting system (RMS), which uses the remote multimission vehicle (RMMV), a large, diesel-powered submersible that carries the detachable AQS-20A minehunting sonar.

The RMMV vehicles were produced by Lockheed Martin, while Raytheon makes the AQS-20As. The Navy's Naval Undersea Warfare Division and LCS program executive office oversee development, test and evaluation of the system.

The RMS system has been in development since the 1990s, and 11 RMMV vehicles have been produced. The Navy plans to restart production next year, and in February hopes to choose a producer for the next round of low-rate initial production RMMVs.

A request for proposals was issued earlier this year but, while the Navy won't confirm the number of respondents, numerous sources indicate only Lockheed responded. Two new developmental vehicles are to be ordered in fiscal 2016 following source selection, at a cost of about $31 million each.

The problem-plagued program has routinely failed or delayed test and evaluation programs and encountered a Nunn-McCurdy breech in 2010. Gilmore noted that reliability has improved since then, but continues to fall far short of the threshold of 75 hours' mean time between operational mission failure (MTBOMF).

But despite all the efforts to improve reliability, Gilmore assessed the RMS system's current overall reliability at 18.8 hours between failure, and the RMMV vehicle at 25.0 hours. He took consistent issue with Navy reliability data, pointing out that in some instances, "the Navy inflated operating time estimates for the MTBOMF calculations by assuming that post-mission analysis time (when the vehicle is not in the water and not operating) could be counted."

Gilmore detailed 41 RMS and RMMV failures from technical evaluation tests that began in September aboard the LCS Independence, mostly while operating in the Gulf of Mexico. The tests were conducted using four RMMVs, vehicles 1, 7, 9 and 10. He noted that failures occurred on all four vehicles in numerous areas, including equipment failures and software problems.

A sampling of failures from the 2015 tests includes faulty depth sensors; throttle failures; alignment issues; inertial navigation unit failures; problems with recovery equipment; bad operator consoles; numerous computer and software connectivity problems; variable depth sonar failures; power failures; offboard communications failures; problems with maintaining line-of-sight communications between the ship and the vehicle; and repeated problems with the vehicle's emergency recovery system, designed to float the craft to the surface should it begin to sink.

In many cases and for a variety of reasons, the LCS was unable to recover the RMMV and it was towed back to base by support craft — an option, Gilmore pointed out, unlikely to be available to an operational LCS using the system in a real minefield. On several occasions, the ship requested support personnel to come aboard to fix an RMS problem.

Gilmore, in his memo to Kendall, urged against relying on Navy reliability data.

"I continue to recommend strongly that the Navy's estimates of RMMV/RMS reliability not be reported to the Congress or used for any other purpose," Gilmore wrote. "To do otherwise could lead many observers to incorrectly conclude that all significant RMS development and fielding challenges have been conquered."

For now, the Navy remains committed to the program.

"In order to ensure better results for upcoming test runs, the Navy is implementing a more robust ready-for-use inspection, procuring additional spares, and providing additional training, additional technicians, better tools, and updated procedures," Chris Johnson, a spokesman for the Naval Sea Systems Command, said Aug. 28.

"While all four RMMVs being utilized in the ongoing TECHEVAL have received a number of upgrades approved through rigorous Reliability Growth Program analysis, there are a number of further upgrades we have identified that could not be installed, such as improved hydraulic actuators, fuel systems, and sensors," the Navy added.

"These upgrades will be incorporated as part of a more thorough design update that will accompany vehicles in the next low-rate initial production procurement. We will also continually look for the means of inserting these and any other reliability upgrades into the existing systems."

Because of ongoing reliability issues, the LCS mission module office recently requested permission from Congress to continue tests into the next fiscal year, which begins Oct. 1. Over the next few weeks, the Navy will evaluate the system and, in October or November, is to decide whether or not to proceed to the initial operational test and evaluation phase.

Email: ccavas@defensenews.com

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