WASHINGTON — Even as the finishing touches are being put on the US Navy's new aircraft carrier Gerald R. Ford, its new-technology aircraft landing system has emerged as the most worrisome element of several new technologies that are key to the first-of-class, $13 billion ship's design.

The new Advanced Arresting Gear (AAG) has yet to be tested with a live aircraft, and the Ford is expected to begin sea trials this fall with the system installed but not fully proven. The Navy is concerned enough to have reviewed the implications of returning to its tried-and-true Mark 7 landing system for the Enterprise, the third ship in the class.

Two sets of AAGs have been procured. One is installed on the Ford, while the other is for the John F. Kennedy, the second ship in the class, which is already under construction.

The Senate Armed Services Committee (SASC) is particularly concerned about the new system and is calling for a Nunn-McCurdy breach to be applied to the AAG, which is a component of the larger carrier program. The SASC, in its markup for the 2017 defense policy bill, cites a cost growth of 186 percent for program acquisition unit cost over the original baseline estimate.

Now, the Department of Defense's Inspector General (DoD IG) in effect underscores the SASC concerns, reporting that the Navy has not effectively managed the program and has not proven the capability or safety of the system. Developmental testing originally scheduled to end in 2009 will continue through 2018, DoD IG observed, and, it noted in its July 5 report, "reliability of the system is uncertain."

DoD IG questioned the future of the AAG and recommends the Navy "perform cost-benefit analyses to determine whether the AAG is an affordable solution for Navy aircraft carriers before deciding to go forward with the system on future aircraft carriers."

Several sources contacted for this story — none of whom wished to be quoted or attributed — agreed with indications the AAG system will work, but possibly not up to the requirements or specifications the Navy desires. A key element, a "water twister" arresting wire shock absorber, will likely not reach the level of durability the service specified, sources said, wearing out after 10 years rather than the 25-year requirement.

But full-scale testing of the AAG, more recently scheduled to be carried out last fall at the Naval Air System Command's aircraft carrier launch and recovery test center at Joint Base McGuire-Dix-Lakehurst, New Jersey, still has not taken place. The latest word is that tests will be carried out later this summer.

The AAG is designed and built by General Atomics, and is supplied as government-furnished equipment to the carrier's builder, Huntington Ingalls Industries' Newport News Shipbuilding in Newport News, Virginia.

General Atomics also builds the new electromagnetic aircraft launch system (EMALS) installed in the new carriers, replacing older, steam-powered catapults.

The EMALS and AAG are key new technologies in the Ford class, the first new US Navy carrier design since the 1960s. The Ford (CVN 78) is nearing completion, construction of the John F. Kennedy (CVN 79) is about 20 percent complete and construction of the Enterprise (CVN 80) is scheduled to begin in 2018.

The Gerald R. Ford is expected to begin sea trials this fall, but the launch and recovery of aircraft is typically not a feature of acceptance trials. Aircraft launch and recovery will take place sometime after the Navy takes delivery and commissions the ship.

The Navy, in its response to the DoD IG report, partially concurred with the findings of cost growth and schedule delays.

"The Navy concurs that the system is not yet ready to test on an aircraft carrier and that the technology was not sufficiently mature for the planned use on CVN 78," the Navy said in a response included in the report. "The Navy has, however, proven the capability and safety of the system by actually arresting aircraft at the Runway Arrested Landing Site (RALS). As of May 24, 2016, the system has arrested 1,253 deadloads at the Jet Car Track Site (JCTS) and 13 aircraft roll-ins at RALS.

"Although testing has not yet occurred on an aircraft carrier, the land-based testing will result in an F/A-18 E/F Aircraft Recovery Bulletin (ARB) which will permit shipboard testing with aircraft."

The Navy acknowledged the cost growth and schedule delays but pushed back on DoD IG assertions that a revision to the Test and Evaluation Master Plan (TEMP) caused further problems. The delay "had no direct impact on redesign, schedule, capability, or cost," the Navy said, and the TEMP would be revised. The Navy noted that the revised TEMP will include a new cost baseline for the AAG program.

A cost-benefit analysis of the AAG as an affordable solution, as recommended by DoD IG, already is underway, the Navy noted, and a recommendation is expected in December.

The DoD IG's audit report on the advanced arresting gear, redacted for public use, is available at http://www.dodig.mil/pubs/report_summary.cfm?id=7016.

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