The boss of Emirates airline has warned Boeing is in the “last chance saloon”, saying he had seen a “progressive decline” in its performance.
Boeing has come under scrutiny after a panel on a 737 Max 9 passenger jet blew off mid-air last month.
Emirates president Sir Tim Clark is a leading industry figure and the airline is a major Boeing customer.
That Emirates would send its engineers to monitor Boeing’s production lines.
In response to Sir Tim’s remarks, Boeing pointed to comments its chief executive, Dave Calhoun, made last week, when he said: “We understand why [customers] are angry and we will work to earn their confidence.”
Emirates told the BBC it had nothing to add to what Sir Tim said in the interview.
“They have got to instil this safety culture which is second to none. They’ve got to get their manufacturing processes under review so there are no corners cut etc,” Sir Tim said.
“I’m sure Dave Calhoun and [commercial head] Stan Deal are on that… this is the last chance saloon,” he added.
Sir Tim was preparing to send Emirates engineers to monitor Boeing’s production lines for the first time.
He said the engineers would observe the production process of the 777 at Boeing and its supplier Spirit AeroSystems.
Emirates is one of Boeing’s biggest customers.
In November, it placed an order for 95 wide-body Boeing 777 and 787 jets, used for long-haul flights, valued at $52bn (£41.2bn) at list prices.
But Boeing hit the headlines in recent weeks despite the Mr Calhoun insisting the company had changed since he took over after former boss Dennis Muilenburg was fired.
On 5 January a door plug on an Alaska Airlines 737 Max 9 blew off shortly after take-off, terrifying passengers, and forcing an emergency return to the Portland, Oregon airport.
The Federal Aviation Administration (FAA) launched an investigation of Boeing’s manufacturing process and barred the firm from expanding production of its popular 737 Max planes.
Some of the company’s biggest airline customers have also expressed concerns, noting that the issues may delay approval of new versions of the 737 Max plane, the Max 7 and Max 10, that are in the works.
In 2018, a similar incident to what happened last month occurred to an older model of Boeing 737 being operated by Southwest Airlines. Debris from an engine failure broke one of the cabin windows while the plane was travelling at 32,000ft. It resulted in one passenger being partially sucked out of the window and she died from her injuries.
The company’s safety record has also been tarnished due to two crashes in late 2018 off the coast of Indonesia and in early 2019 outside Ethiopia’s capital Addis Ababa.
A total of 346 people were killed in the crashes, which were caused by flawed flight control software.
