The Qantas Airbus A380 aircraft after a forced emergency landing in Singapore
QANTAS has fast-tracked modification of Rolls-Royce engines on its Boeing 747-400 fleet because crucial parts are failing at up to three times the rate predicted by the manufacturer.
Qantas suffered three engine failures involving high-pressure compressor (HPC) blades on Rolls-Royce RB211 engines last year and has been hit by another three so far this year.
These include an engine failure near Johannesburg on a jumbo jet carrying the South African rugby union team on Saturday and a problem near Bangkok last month.
This is significantly higher than statistical modelling by Rolls-Royce, indicating the rate should be 0.8 events a year, contained in an Australian Transport Safety Bureau report on one of last year’s incidents near Singapore, The Australian reports.
The problem is not unique to Qantas: the RB211s have an acknowledged problem with disintegrating HPC blades and in a 2009 modification Rolls-Royce introduced a redesigned blade.
The engine manufacturer discovered several years ago that distortion of the compressor case was causing the tips of fan blades to rub and, eventually, to crack and disintegrate. Blade failures seriously damage engines and in rare cases can send shrapnel ripping through the sides of engines.
Rolls-Royce issued a service bulletin in 2006 aimed at reducing the distortion but opted to redesign the fan blades after the further failures in two engines.
Qantas has followed the manufacturer’s recommendations for changing the blades during major engine overhauls since early 2009 and has so far modified 25 percent of its fleet.
The recent string of engine failures has prompted it to fast-track the process and may lead it to change the way it operates its jumbo jets.
“We are accelerating the rate at which we send RB211s for overhaul in order to fast-track this modification and others over the next 12 to 18 months,” a spokesman said.
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