The latest edition of the Government Accountability Office’s (GAO) annual assessment of the largest complex Defense Department programs clarifies delays in Ship-to-Shore Connector production and acquisition lie in the gearbox and propulsion control.

In March, the Navy’s FY ’20 budget request cut the Textron Inc. [TXT] Ship-to-Shore Connector (SSC) Landing Craft Air Cushion (LCAC)-100 craft over the Future Years Defense Programs (FYDP) from 32 vessels through FY ’23 to 21 vessels through FY ’24. The Navy not only cut the total number of craft in the FYDP compared to the FY ’19 request, but delayed additional acquisitions until FY ’21 (Defense Daily, March 15).

Rendering of the Ship-to-Shore Connector, a replacement for the landing craft air cushion (LCAC) built by Textron. (Image: Textron)

Navy budget documents said this cut was due to contractual and delivery delays. Chief of Naval Operations Adm. John Richardson commented at the time the service is ready to commit to the vessels when they reach the right level of maturity and reliability.

A Navy spokesperson also told Defense Daily the problems were related to electrical systems stability and command, control, communications, computers and navigation (C4N) integration (Defense Daily, April 3).

Now the new GAO report published on May 7, “Weapon Systems Annual Assessment: Limited Use of Knowledge-Based Practices Continues to Undercut DOD’s Investments,” revealed the craft’s gearbox was showing gear slippage during testing, after it already dealt with premature wear. The program is working on engineering solutions for both the propulsion and lift elements, GAO added.

The report noted “this is the third iteration of design changes related to problems with the gearbox. The program expects that once the revised design is finalized and manufactured, the contractor will have to retrofit the craft already in production.”

Then, in October 2018, a LCAC-100 test and training prototype vessel lost propulsion and drifted into a bridge during pre-delivery testing.

According to the report, Navy officials found overheating in the propulsion power control module was the root cause. Since the incident, Textron developed a heat exchanger and in November 2018 Textron “demonstrated it could significantly lower the module’s internal temperature.”

The Navy plans to apply this solution to the vessels currently in production. Textron has a contract to produce the first nine SSCs, including LCAC-100.

The GAO warned while Textron and the Navy will test Craft 100 while the contractor is producing the eight other vessels, “this concurrency increases the risk that the program will discover deficiencies that could require costly design changes and modifications to units in production.”

The report said program officials are “uncertain about the production schedule because solutions to the technical problems are pending.”

The Navy still expects Craft 100 to be delivered in July 2019, a 15-month delay beyond last year’s GAO assessment. The Navy expects delivery of the second craft “several months” beyond the first.

The report also warned the Navy cannot verify it has addressed all the known deficiencies in realistic operational conditions until operational testing of Craft 100, which can only occur after the program office takes delivery of it later this year. Operational testing is then slated to start in the summer of 2020 and finish two months before the Navy declares SSC initial operational capability (IOC) in August 2020, when the first vessels are scheduled to deploy.

“Should the Navy discover deficiencies during operational testing, it may face a choice to delay initial capability or deliver SSC craft that are operationally ineffective or unsuitable, as it has done in other programs,” the report warned.

The Navy plans for the SSCs to replace the current aging fleet of hovercraft and serve for 30 years, The craft will transport payloads at over-the-horizon distances from amphibious ships and mobile landing platforms. The Navy plans to buy 72 operational vessels after the initial test and training craft. The SSCs feature improved engines, fly-by-wire controls, higher payloads over legacy vessels, simpler maintenance, and a smaller crew.