Acting Secretary of Defense Patrick Shanahan. AP Photo/Evan Vucci

Acting Secretary of Defense Patrick Shanahan, a former Boeing executive, has been railing against Lockheed Martin's F-35 stealth fighter in private, Politico reported on Wednesday, citing former government officials.

At one point, one of the former officials told Politico, Shanahan described the Joint Strike Fighter program as "f---ed up" and argued that Boeing could have done a better job.

Shanahan has signed an ethics agreement recusing himself from participating in matters involving his former company, a leading US defense contractor.

The new defense chief, a former Boeing employee, has reportedly been extremely critical of Lockheed Martin's embattled F-35 Lightning II Joint Strike Fighter in private meetings, raising questions about whether he is biased in overseeing the largest weapons program in history.

Acting Secretary of Defense Patrick Shanahan, who took over when Jim Mattis resigned, spent over 30 years at Boeing before joining the Department of Defense in 2017 as the deputy secretary of defense.

Though he signed an ethics agreement recusing himself from matters involving Boeing, Shanahan has continuously bashed the F-35, a key program for one of Boeing's top competitors, in high-level meetings at the Pentagon and at other private gatherings, Politico reported on Wednesday, citing former government officials who heard Shanahan make the comments.

US Air Force F-35 Lightning II joint strike fighter crew chief Tech. Sgt. Brian West watches his aircraft approach for the first time at Florida's Eglin Air Force Base in 2011. US Air Force Photo

A former senior Defense Department official told Politico that Shanahan described the F-35 stealth fighter as "f---ed up" and said its maker, Lockheed Martin, "doesn't know how to run a program."

"If it had gone to Boeing, it would be done much better," the former official recalled Shanahan saying, Politico reported.

Lockheed beat out Boeing in the Joint Strike Fighter competition, with the Department of Defense ultimately picking Lockheed's X-35 - which became the F-35 - over Boeing's X-32 in 2001. Had Boeing been awarded the contract, the military's JSF might look very different.

A former Trump administration official told Politico that Shanahan "dumped" on the aircraft regularly and "went off" on the program last year.

"He would complain about Lockheed's timing and their inability to deliver, and from a Boeing point of view, say things like, 'We would never do that,'" the former official said.

In other private meetings, the former official added, Shanahan has called the program "unsustainable," complaining about the cost of the stealth fighters, with separate versions built for the Navy, the Marines, and the Air Force. The F-35 is expected to cost more than $1 trillion over the life of the program, making it the most expensive weapon in US military history.

Maintainers from the 388th Maintenance Group preparing an F-35A for its mission. United States Air Force photo/Todd Cromar

Current administration officials, however, told Politico that Shanahan's comments were being taken out of context, stressing that he was not advocating for Boeing.

"I don't believe that's the case at all. I think he's agnostic toward Boeing at best," one official said, adding, "I don't think there's any intent to have Boeing favored in the building."

It's not the first time Shanahan's loyalties have been called into question. The Pentagon is said to be planning a request for $1.2 billion for 12 Boeing F-15X fighter jets, a decision that was made at Shanahan's urging, Bloomberg reported.

Air Force leaders had previously said there was no reason to buy these advanced fourth-generation fighters because they lack the necessary stealth capabilities provided by fifth-generation planes like the F-35, according to Defense News.

A formation of 35 F-35A Lightning IIs, from the 388th and 419th Fighter Wings, fly over the Utah Test and Training Range as part of an exercise in November. U.S. Air Force photo by Staff Sgt. Andrew Lee

Shanahan's office told Politico he remained committed to his recusal. In public, he has spoken highly of the F-35 program.

"The F-35 is our future," he said in September at the Air Force Association's Air, Space & Cyber Conference.

"I think we can all agree that it is a remarkable aircraft, with eye-watering capabilities critical to the high-end fight," he added. "I tip my hat to its broad team of government, industry, and international partners. Having worked on programs of similar size and complexity, I have enormous respect for your talent and commitment."

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