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QantasLink knew engine flaw before failure: report
7th April 2009, 6:00 WST
A Perth-bound aircraft that experienced severe engine failure after taking off from Newman in 2007 had a serious engine defect that was known about, Australia’s safety investigator has found.
The Australian Transport Safety Bureau found in its report, issued yesterday, that the engines of the Qantas-Link Boeing 717, carrying 93 passengers, had a series of similar failures with other airlines as well as QantasLink.
The airline was in the process of replacing the faulty high-pressure turbine blades when the “significant event” occurred.
The aircraft had just taken off from Newman on July 13 and was climbing through 14,000ft when the passengers and crew heard a loud bang followed by vibrations.
The ATSB found that the failure of a single Stage 1 high-pressure turbine blade had caused all the blades on the Rolls-Royce Deutschland BR715 number two engine (right side) to shear off.
These turbine blades are directly behind the engine’s combustor and are at the heart of an aircraft’s motor.
At full power, each of the 80 blades generates the same capacity as a Formula One racing car.
In November 2004, Rolls-Royce and Boeing advised airlines to replace the blades “at the earliest opportunity” with new, higher quality ones that would not fail.
When the engine on the 717 failed, the blades had not been replaced but the operator was in the “process” of doing so.
But the operator, National Jet Systems on behalf of QantasLink, had conducted an ultrasonic inspection of all the engines as instructed to detect for any cracks in the blades.
Since the incident, all QantasLink’s 717s have had the high-pressure turbine blades replaced.
The 717, which entered service in 1999, has a perfect safety record.
The aircraft is used extensively in WA and is popular with passengers.