THE United States has just finished the first operational deployment of the controversial F-35 stealth fighter.

We don’t know how it went.

We won’t know how it went.

The Pentagon has classified its report into the most significant challenges the US Marine Corps encountered in Japan and when taking its F-35B ‘jump jet’ variant to sea aboard the USS Wasp in January.

We know problems emerged.

“While the Marine Corps recognises the advanced warfighting capabilities the F-35 will bring to the Pacific, it is facing challenges operating in the area,” an unclassified summary of the report states. “In particular, it is uncertain how long the F-35 can effectively operate if ALIS becomes disconnected from the aircraft.”

This refers to the aircraft’s self diagnostic system, an artificial intelligence (called ALIS) intended to make critical maintenance easier and ensure it is up to standard.

And it’s not known if the ‘airframe issues’ which caused one of the F-35Bs to make an emergency landing in Japan recently is part of the Marine Corp’s concerns.

The United Kingdom is purchasing the ‘jump jet’ F-35B. Other nations such as Australia, Norway, Italy, and Candada have all contributed to the stealth fighter’s exorbitant development costs, as well as committed to buying it.

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But the Pentagon earlier this month suspended all deliveries of the new jet from its manufacturer, Lockheed Martin.

This is because of a dispute over who was responsible for the cost of repairing serious production faults discovered upon delivery.

TROUBLED TRILLION-DOLLAR TURKEY

Some 16 F-35Bs in Marine Fighter Attack Squadron 121 were deployed to Japan last year. In January, these went to sea in a heavily promoted deployment aboard the USS Wasp.

The US Marine Corps has plans to buy 353 of the ‘jump jet’ variant to replace its AV-8B Harrier and F/A-18 Hornets.

What we know of the F-35Bs performance comes from a Government Accountability Office assessment of the state of the program.

“The F-35 program does not currently disseminate or make available lessons learned across all services, although program officials agreed that doing so would be beneficial,” it found.

“The services are at risk of not having access to key information that could affect their movements, exercises, operations, and sustainment of the aircraft in the Pacific and other areas where they operate. Now is the time for DOD to make sure that lessons learned are communicated effectively across all services.”

And, hopefully, all allies.

The F-35 stealth fighter, which is the world’s most costly defence project ever, is also known to have software problems associated with its one greatest advantage — the ability to ‘network’ with nearby aircraft, ships, soldiers and satellites.

Whether or not this was raised in the Pentagon report is unknown.

But spare parts are clearly part of the issue.

“The Marine Corps has also encountered several challenges with the F-35’s supply chain since beginning flight operations in January 2017. Further details are provided in our classified report ...”

DELIVERY SUSPENDED

The dispute between the Pentagon and Lockheed Martin has remained unresolved since it emerged earlier this month.

The dispute is specifically over who is responsible for paying for production errors. Neither US Government nor Lockheed Martin inspectors identified the issue while the jets were on the production lines.

It’s not the first time such a suspension has been enforced.

No new F-35s were accepted for more than 30 days last year after it was discovered corrosion was affecting the join between carbon fibre panels and the aluminium airframe. A recall had to be applied to more than 200 F-35s.

In 2016, a delivery halt was related to insulation problems with the fuel lines and tanks.

The new, unspecified, problems will require technicians to travel the world to wherever the stealth fighter is located.

It’s clearly not a cheap job.

“We are still progressing along with the Joint Program Office on that,” Lockheed Chairman, President and CEO Marillyn Hewson said in a statement. “It’s just a temporary suspension that they have on accepting some aircraft until we reach agreement on a contractual issue. So we’re working through that contractual issue with them.”

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The extent to which these production defects apply to the handful of F-35A fighters so far delivered to the Australian Air Force has not been revealed, nor whom will wear the cost of remediating the problems.

Reuters reports two sources as saying two unspecified foreign customers had also stopped accepting F-35s as a result of the new issues.