"During scheduled maintenance, we identified a component that did not perform as designed," the US aerospace giant told AFP in a statement.

"Our team is replacing the part and capturing any learnings from the component and will resume flight testing when ready," it added, confirming an earlier report by specialist website The Air Current.

Boeing has been beset in recent years with concerns about safety and quality control, with a near-catastrophic incident on an Alaska Airlines Boeing 737 MAX in January bringing renewed pressure on the company.

Boeing's new chief executive Kelly Ortberg, 64, took over earlier this month on a pledge to restore trust in the embattled manufacturer, and announced he would be based in Seattle to be close to the firm's commercial airplane programs.

Boeing's 777X widebody program, unveiled in November 2013, is the latest addition to its popular 777 family.

The new twin-aisle aircraft is destined to be the world's largest twin-engine jet in operation. More than 500 777X aircraft have already been ordered, but have yet to enter commercial service.

The part that brought about the suspension of flight testing is custom to the 777-9 model, and connects the engine to the aircraft structure, Boeing said.

The other 777-9s used for testing are all currently being inspected following the incident, it added.

Boeing's new aircraft will be available in three models: the 777-8, the 777-9 and the 777-8 cargo.

The aircraft's entry into service was originally scheduled for 2020, but due to problems during the certification process it has now been delayed to 2025.

Although the 777X has still not received the go-ahead from the US Federal Aviation Administration (FAA), Boeing did cross an important milestone in July this year.

Following a large number of test flights, it obtained permission to start testing the 777-9 with FAA representatives on board.

AzVision.az

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