The sky is falling — at least on Boeing.

A second whistleblower has died under mysterious circumstances, just two months after another one allegedly shot himself in the head — and the attorneys for both men hope their deaths don’t scare away the at least 10 other whistleblowers who want the company to clean up its act.

Joshua Dean, 45, a former quality auditor at Spirit AeroSystems which assembles fuselage sections for Boeing, died Tuesday morning from a fast-growing mystery infection.

Dean’s death comes less than two months after Boeing whistleblower John Barnett, 62, died from an apparent self-inflicted gunshot wound on March 9.

Barnett, who had worked for Boeing for 32 years, was found dead in his Dodge Ram truck holding a silver pistol in his hand in the parking lot of his South Carolina hotel after he failed to show up for the second part of his testimony for a bombshell lawsuit against the company.

At the same time, Boeing said last month that it lost $355 million on falling revenue in the first quarter, another sign of the crisis gripping the aircraft manufacturer as it faces increasing scrutiny over the safety of its planes and accusations of shoddy work from a growing number of surviving whistleblowers.

It was announced abruptly in March that Boeing CEO Dave Calhoun would step down by the end of the year in a move widely seen as a reaction to the ongoing safety crises.

Brian Knowles, a Charleston, South Carolina, attorney who represented both Barnett and Dean hope their deaths were not in vain.

“These men were heroes. So are all the whistleblowers. They loved the company and wanted to help the company do better,” Knowles told The Post.

“They didn’t speak out to be aggravating or for fame. They’re raising concerns because people’s lives are at stake.”

Knowles and others inside the Boeing scandals are hesitant to speculate about conspiracy theories swirling around the two whistleblower deaths.

“I knew John Barnett for seven years and never saw anything that would indicate he would take his own life,” Knowles told The Post.

“Then again, I’ve never dealt with someone who did (commit suicide.) So maybe you don’t see the signs. I don’t know.”

Knowles pointed out that the Charleston, SC police are still wrapping up their investigation of Barnett’s death — and that it may take some weeks for tests to reveal more about Dean’s passing.

“It’s a stunning loss,” Spirit AeroSystems spokesman Joe Buccino said of Dean. (The company is not to be confused with Spirit Airlines.) “Our focus here has been on his loved ones.”

Buccino insisted that Spirit “encourages” employees to come forth with their concerns and that they are then “cloaked under protection.”

A Boeing spokeswoman declined to answer questions on Barnett but in a statement, said that OSHA had determined Barnett was not retaliated against, and that the company’s own analysis found that the issues he raised “did not affect airplane safety.”

“We are saddened by Mr. Barnett’s passing and our thoughts continue to be with his family and friends,” the statement said.

“We encourage all employees to speak up when issues arise. Retaliation is strictly prohibited at Boeing.”

It’s news to other Boeing whistleblowers that Boeing and Spirit “encourage” workers to speak out.

Instead, they say, they’ve either been retaliated against — or ignored.

Ed Pierson, 61, a former senior manager at Boeing’s 737 factory in Renton, Washington, left Boeing six years ago and created the Foundation for Aviation Safety.

He had tried in vain to get Boeing executives to shut down production of the plane before the two Boeing 737 Max crashes in 2018 and 2019 that killed 346 people and led to the planes being grounded.

“It’s an unstable company right now from the top to the bottom,” Pierson told The Post. “Senior corporate leadership is so fixated on not admitting the truth that they can’t admit anything.”

Pierson did not mince words when he testified before Congress last month about what he called the “criminal cover-up” he believes Boeing bosses have led.

“Boeing is an American icon,” Pierson said. “This company is incredibly important to our country, both economically and in terms of national security with its commercial aviation side and it military defense work. But it doesn’t work when you have the wrong people driving the bus.”

Barnett was a quality control engineer who worked for Boeing for more than three decades before he retired in 2017.

He broke his silence two years later to warn that Boeing cut corners to speed its 787 Dreamliners into service and in numerous interviews described how he had complained internally to the company about what he claimed were serious safety flaws.

After his apparent suicide in March, Boeing employees told The Post that Barnett had made “powerful enemies” and one said workers were skeptical that Barnett’s death was suicide.

Dean had raised the alarm in 2022, while working at Spirit AeroSystems, a Wichita, Kansas-based company which manufactures major aircraft parts for Boeing.

He was a quality auditor when he raised concerns about improperly drilled bulkhead holes on parts for the 737 Max.

But, he alleged, flagging the issue with his management had no effect.

Less than a year later he was fired.

“I think they were sending out a message to anybody else,” Dean later told NPR of his firing. “If you are too loud, we will silence you.”

Boeing has been dogged by whistleblower testimony and Congressional investigations.

A scathing House report issued in Sept. 2020 found that the two 737 Max crashes were the “horrific culmination” of “repeated and serious failures” by the company and air safety regulators.

“Boeing was a Seattle company. Back in the day a typical Boeing CEO was a hyper-midwestern farm boy who saw airplanes as a kid and went off to Seattle to conquer the world,” Craig Jenks, who runs the Airline/Aircraft Projects Inc. consultancy, told The Post.

“Then the finance people started taking over in the 1980s and they moved the corporate headquarters to Chicago and then to DC. It means senior management is never around the factory floor.”

The most headline-grabbing safety lapse was in January, when a fuselage panel blew off a new Alaskan Airlines 737 — although late last month, a safety slide fell off a Delta 767 and washed up, with perfect irony, in front of the home of an attorney suing Boeing over safety issues.

In the Alaskan airlines case, a whistleblower told the Seattle Times that the fault lay with Boeing, whose records showed that after the fuselage was delivered by Spirit, a panel had been removed at Boeing’s Renton factory and re-installed minus four crucial bolts.

In the air, the panel flew off — fortunately, at a low enough altitude that the plane did not depressurize.

“It is …very, very stupid and speaks volumes about the quality culture at certain portions of the business,” the whistleblower told the Seattle Times.

A number of Boeing employees have alleged to the New York Times that the manufacturer has allowed mechanics to sign off on their own work, cutting out a layer of safety assurance.

“Profit has overtaken the historically famous pride of Boeing,” Peter Lake, an aviation expert who has investigated a number of plane crashes over the years, told The Post.

“It’s all corporate greed now. It’s become a standing joke that when there’s any malfunction in an airplane people say it’s Boeing.

“Southwest Airlines had an engine failure recently and people ignorantly blamed Boeing. That shows what a cloud the company is under.

“Who knows if they’ll be able to pull themselves out of this disaster?”