One of the many unanswered questions arising from last night’s uncontained failure of an engine on a China Eastern A330 that had left Sydney on its way to Shanghai is what if any damage was sustained by the fuselage of the jet.
At this stage there is no clear imagery of any such damage on its exterior, and none of the passenger interviews suggest any penetration of fragments of the engine inside the cabin.
The jet flew for about an hour before making its return landing at Sydney Airport and there is no indication as to any handling issues that the pilots may have dealt with, other than their obviously following single engine flight procedures that are an integral part of their training.
Uncontained engine failures are so called because the outer structure of the power plant was broken, defeating the design specifications intended to prevent parts of an engine from piercing the airframe or hitting critical control surfaces on the adjacent wing or the damage sensitive tail area.
However one of the puzzling aspects of this incident is that there is more superficial evidence of cowling damage than of damage to the heavy components of the engine within. A clear picture of what happened remains elusive at this hour, although possibly not for much longer.
There have been incidents with this particular version of the engine of the sound proofing cladding in the cowling around the forward part of the assembly collapsing inwards and being ingested by the engine within.
The engine makers insist that such uncontained failures are rare. But they are potentially very serious and often spectacular, and the most dangerous and high profile of all involved the Qantas A380 QF32 incident near Singapore on November 4, 2010.
The engine type was a Rolls-Royce Trent 772 in the case of last night’s incident, and a much larger and more powerful Trent 900 in the QF32 incident. Although both are made by Rolls-Royce and share a common family designation, they differ from each other significantly in output and critical components.
This entry in the Aviation Herald contains more photos of the damage and draws attention to a similar incident in an Egyptian A330-200 several weeks ago.
The Aviation Herald says the destructive event occurred just after take off. Had this failure happened shortly before takeoff it would have been highly likely that the crew would have elected to continue the takeoff and deal with the consequences once airborne, rather than add to the risks of the situation by aborting the take off in a heavy jet and possibly experiencing an undercarriage failure or fire on the ground and at an unsafe speed.
All aspects of the management of the crisis will be examined in more detail by the yet-to-be announced ATSB investigation which inevitably occurs when airliners experience major failures in Australian airspace or airport terminal zones.