- One Boeing 787 experienced engine crack during taxi test in July
- Inspectors found a second problem on another plane that had yet to fly
- The Dreamliner is first commercial airliner made mostly of carbon composites
(CNN) -- Two months after a Boeing 787 experienced an engine crack and failure during a low-speed taxi test, federal plane inspectors have found a second engine problem on a different Dreamliner, the National Transportation Safety Board announced.
The second airplane with a cracked fan midshaft had yet to fly, according to NTSB investigators who have completed an initial inspection of all in-service GEnx turbofan engines.
The engines are manufactured by General Electric at a facility in Cincinnati.
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The engine failure on July 28 occurred during a taxi test at Charleston International Airport in South Carolina. No passengers were on board, and no injuries were reported, although burning debris from the failure did cause a small brush fire near the tarmac.
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This month, a Boeing 747 experienced a loss of power in one of its engines during takeoff in Shanghai. That incident is under investigation by the Civil Aviation Administration of China.
The NTSB said this week that preliminary findings in the Shanghai incident revealed that the fan midshaft was "intact and showed no indications of cracking."
The Federal Aviation Administration, General Electric and Boeing are involved in the investigation.
Boeing rolled out the 787 Dreamliner last year, three years late and billions of dollars over budget.
It is the first commercial airliner made mostly of carbon composites, requiring less fuel than conventional airliners.
