REUTERS/Matt Mills McKnight Boeing employees working on the tail of a 737 NG at the Boeing plant in Renton, Washington, in December 2015.

Qantas has found cracks in a 737 Next Generation plane, adding to Boeing’s woes.

The cracking problem had already been discovered by Boeing, prompting the US’s aviation regulator to order airlines to inspect planes that had made more than 30,000 flights. But this Qantas plane had made fewer than 27,000 flights.

More than 50 737NG planes have now been grounded around the world, according to Agence France-Presse.

Boeing was already facing a global crisis with its 737 Max planes, which are grounded after two fatal crashes killed 346 people.

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Boeing is facing a fresh and growing crisis after Qantas found cracks in a 737 Next Generation plane, adding to a growing number of airlines reporting such issues and grounding some of the planes as a result.

Qantas on Thursday said it found cracks in one of its 737NG planes and planned to repair it while inspecting 33 other planes this week.

The airline said it did not see an immediate safety risk and would “never operate an aircraft unless it was completely safe to do so,” the BBC reported.

The discovery comes a month after Boeing discovered the cracking problem in the 737NG, prompting the US Federal Aviation Administration to instruct airlines that fly the planes to inspect them. Thousands of 737NG planes are in service globally.

Those inspections were instructed for planes that had made more than 30,000 flights, while Qantas said its plane had made fewer than 27,000 flights, the BBC reported.

Reuters Qantas Airways planes.

A source told Reuters that cracks were also found Wednesday on another Qantas plane that had flown almost 27,500 times.

And another source also told Reuters that the US carrier Southwest Airlines also found cracks in one of its planes that had flown about 28,500 times.

The plane grounded by Qantas adds to a growing list of 737NG planes grounded by airlines. Korean Air grounded nine of the planes Friday after cracks were discovered, and the news agency Agence France-Presse reports that up to 50 737NG planes have now been grounded around the world.

The cracks are on an area of the plane called the pickle fork, which connects the plane body, wing structure, and landing gear.

Qantas said “detailed analysis” by Boeing showed that “even when a crack is present, it does not immediately compromise the safety of the aircraft, as indicated by the timeframe given by regulators to perform the checks,” ABC News reported.

But Australia’s aircraft engineers association called on the airline to ground all of its 737NG planes.

Its secretary said on Thursday that the crack “was about an inch long, it’s very small,” but added that “these things do propagate very quickly when they’re under load … It’s when that grows, and that grows very quickly, that you have problems,” The Guardian reported.

David Ryder/Getty Images Undelivered Boeing 737 Max planes sitting idle at a Boeing property in Seattle in August.

The new problem is distinct from Boeing’s ongoing crisis over its 737 Max planes, which have been grounded around the world since a combined 346 people were killed in crashes in October 2018 and this past March. Those crashes have been linked to software known as MCAS, which Boeing has been working to fix.

Boeing CEO Dennis Muilenburg testified before Congress about the issue on Wednesday, when lawmakers accused him of “pushing profits over quality and safety.” Muilenburg directly apologised to victims’ families and said the company “made some mistakes” in the plane’s design.

Boeing has lost billions, and airlines around the world are demanding compensation as they cancel flights, reduce routes, have new deliveries stalled, and pay to maintain the planes that were delivered, which they will not be able to fly until regulators approve Boeing’s updates.

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