Tim Clark, the president of Emirates, has joined a chorus of airline executives in warning that Boeing is running out of time to restore its reputation following a series of safety and manufacturing blunders.

In an interview with the Financial Times published Sunday, Clark said he had seen a “progressive decline” in Boeing’s standards, which he put down to long-running management and governance missteps, including prioritizing profit over engineering excellence.

“They’ve got to get their manufacturing processes under review so there are no corners cut etc. I’m sure Dave Calhoun and Stan Deal are on that,” he added, referring to Boeing’s CEO and head of commercial airplanes respectively. “This is the last chance saloon.”

Emirates declined to comment further.

Clark isn’t the first airline boss to criticize Boeing since part of the fuselage of a 737 Max 9 blew out mid-flight in early January. In an interview with CNBC last month, United CEO Scott Kirby lamented the planemaker’s “consistent manufacturing challenges.”

“I think the Max 9 grounding is probably the straw that broke the camel’s back for us,” he said. “We’re going to build a plan that doesn’t have the Max 10 in it,” he added, referring to Boeing’s newer, larger 737 model. The CEOs of American and Alaska have also voiced their frustration.

But Clark is one of the most high-profile figures in aviation, having held senior roles at Emirates since the 1980s, and the Dubai-based airline is one of Boeing’s biggest customers. In November, Emirates placed an order for 95 wide-body Boeing 777 and 787 jets, used for long-haul flights, valued at $52 billion in total.

The US aviation regulator is already investigating the beleaguered planemaker’s manufacturing practices after January’s incident in which a so-called door plug shot out only a few minutes into an Alaska Airlines flight, forcing the pilot to make an emergency landing.

The blowout added to a string of quality and safety issues with Boeing planes in recent years. Two crashes in Indonesia and Ethiopia in October 2018 and March 2019 respectively, which killed 346 people, led to the long-term grounding of some Boeing jets and delayed deliveries of others.

Unlike after those fatal crashes, Boeing has been quick to accept responsibility for the Alaska Airlines incident and pledged to do better.

Still, Clark said that Emirates would, for the first time, send its own engineers to observe the production process of the 777 at Boeing and its supplier Spirit AeroSystems.

“The fact that we’re having to do that is testament to what has happened,” he told the Financial Times. Boeing “needs a root-and-branch look at how it goes about producing aeroplanes,” he added.

“Will Boeing restore itself to its former glory? Of course it will. Will Boeing continue to produce and design great aeroplanes, well-put together, reliable, for the customer base? I’m sure they will. But they’ve got to put the house in order at the moment. And this is a major shift in the priorities.”

When contacted for comment, Boeing referred CNN to Calhoun’s remarks to analysts on an earnings call last week in which he said that increased scrutiny from regulators and customers “will make us better.”

“We will go slow to go fast and we will encourage and reward employees for speaking up to slow things down if that’s what’s needed,” he added.

Ryanair — Europe’s largest airline and another of Boeing’s biggest customers — said last week that it was putting more of its own engineers in factories that build Boeing planes to run extra checks.

CEO Michael O’Leary said he has “a lot of confidence” in Calhoun and chief financial officer Brian West to turn the company around.