One of the key components of the Navy’s MCM mission module for the LCS is the Remote Minehunting System (RMS). It consists of an unmanned underwater vehicle, the Remote Multi-Mission Vehicle (RMMV), currently v4.2, that tows a minehunting sonar, the AQS-20. This system has demonstrated severe reliability and performance problems. As the most recent 2014 Annual Report from Director, Operational Testing and Evaluation summarizes it,
“… the combined results of shore-based and LCS-based testing conducted since the program was recertified following a Nunn-McCurdy in 2010 have not demonstrated that an LCS equipped with an MCM mission package that includes two RMMVs and three AN/AQS-20A sonars will be able to support the sustained area coverage rate that the Navy has established for the Increment 1 MCM mission package.”
The two specific concerns are reliability and performance. The two must both be achieved to have a viable system. It does no good to have a reliable system that can’t perform or, conversely, a system that performs but is unreliable.
Here is DOT&E’s assessment of the RMMV reliability.
“The reliability of the v4.2 RMMV during combined developmental and integrated testing completed in FY14 was 31.3 hours MTBOMF [ed., Mean Time Between Operational Mission Failure], which is well below the required reliability of 75 hours MTBOMF.”
Given the extended period of development that the RMMV has undergone, this level of reliability is extremely troubling.
While reliability is problematic, to say the least, DOT&E points out that what’s even worse is that the recovery of the RMS from failures is largely relegated to off-board maintenance. The LCS crew has very limited on-board ability to recover from failures. This is a consequence of the LCS operating model of limited on-board maintenance.
It’s not just the RMMV that has problems. The AQS-20 sonar has consistently failed to meet performance specifications.
“Contact depth (vertical localization) errors and false classification density exceeded Navy limits in all AQS-20A operating modes.”
“The sensor also has trouble meeting the probability of detection and classification requirement in shallow waters and RMS has difficulty guiding the sensor over bottom contacts for identification in deep water.”
Communications are a problem, as well.
“RMS radios have had difficulty establishing reliable communications with the LCS during developmental testing, and once communications are established, the current communications systems do not support RMMV mine identification operations beyond the horizon. Although the RMMV can search autonomously while operating over the horizon from the LCS, it currently only can conduct operations to reacquire and identify bottom mines within the range of Ultra High Frequency communications. This limitation will complicate MCM operations in long shipping channels, and may make it necessary to clear a series of LCS operating areas to allow MCM operations to progress along the channel. The cleared operating areas will be needed to keep the LCS and its crew out of mined waters. The additional effort required to clear these LCS operating areas would increase the demand for mine clearance and delay attainment of strategic objectives. This issue is not new to RMS; however, it did not become operationally significant until the Navy decertified the MH-60S helicopter for towing MCM devices, including the AN/AQS-20A/B sensor.”
Simply launching and recovering the RMMV is a challenge.
class LCS has had difficulty launching and recovering the RMMV because of the vehicle’s erratic motion in the ship’s wake.” Independence
Overall system reliability is poor. DOT&E noted that in the most recent 3-week period of intensive testing, the system was only able to operate for 50 hours (16 hours per week).
The DOT&E report contains many, many more examples of specific failures and shortcomings in the RMS – too many to document in this limited space. It’s clear that the Navy’s all-in bet on the LCS as the only MCM vessel in the fleet and the use of unproven (largely non-existent) technology has been an abysmal failure thus far. Given that mines are, arguably, the biggest threat the Navy faces, this is extremely bad news. Rather than pausing this problematic development effort long enough to beef up more conventional MCM capabilities throughout the fleet in order to buy time for continued development, the Navy has doubled down on their bet. While a reduced capability version of the MCM module will, undoubtedly, eventually be fielded, it will surely prove woefully inadequate to the task when ultimately called on.