Update on Qantas QF32 Airbus 380 Incident
I wrote previously about the Qantas flight QF32 Airbus A380 which made an emergency landing in Singapore last month.
Following a normal takeoff, the crew retracted the landing gear and flaps. The crew reported that, while maintaining 250 kts in the climb and passing 7,000 ft above mean sea level, they heard two almost coincident ‘loud bangs’, followed shortly after by indications of a failure of the No 2 engine.
The investigation is still continuing but the initial issue, “an uncontained failure of the Intermediate Pressure turbine disc” has been identified.
Recent examination of components removed from the failed engine at the Rolls-Royce plc facility in Derby, United Kingdom, has identified the presence of fatigue cracking within a stub pipe that feeds oil into the High Pressure (HP) / Intermediate Pressure (IP) bearing structure. While the analysis of the engine failure is ongoing, it has been identified that the leakage of oil into the HP/IP bearing structure buffer space (and a subsequent oil fire within that area) was central to the engine failure and IP turbine disc liberation event.
Further examination of the cracked area has identified the axial misalignment of an area of counter‑boring within the inner diameter of the stub pipe; the misalignment having produced a localised thinning of the pipe wall on one side. The area of fatigue cracking was associated with the area of pipe wall thinning (Figure 1).
The Australian Transport Safety Bureau have released a Safety Recommendation to Rolls-Royce plc to address the safety issue. You can read the full recommendation and justification in the Recommendation tab of the report: Investigation: AO-2010-089 – Inflight engine failure – Qantas, Airbus A380, VH-OQA, overhead Batam Island, Indonesia, 4 November 2010
Meanwhile, the Royal Aeronautical Society have published an exclusive interview with Captain David Evans, who was in the observer’s seat when the incident occurred. The detail of the event and the crews reactions makes for a fascinating read:
It was getting very confusing with the avalanche of messages we were getting. So the only course of action we have is the discipline of following the ECAM and dealing with each one as we came through with them. The engine shutdown was completed, the hydraulic systems were dealt with and then the next systems we were looking at were the loss of various flight controls. This was due to the degradation and the loss of some electrical buses, bus 1 and 2 had failed. Basically, just going through the ECAM actions, acknowledging them and working through the systems display to see what was working and was not.
The next thing we were dealing with was the fuel. We had some obvious leaks, some severe, out of the Engine 2 feedtank. We dispatched the second officer back to the cabin to have a look and there was a fairly significant fuel trail behind the aircraft – or fluid trail because at that stage we couldn’t determine whether it was hydraulic fluid or fuel. We were getting messages about imbalance, losing fuel out of one side and not the other. And those messages were some of the ECAM messages that we didn’t follow. We were very concerned the damage to the galleries, the forward and aft transfer galleries, whether they were intact, whether we should be transferring fuel. We elected not to.
The emphasis on the passengers really stands out, in my opinion:
I think most probably the most serious part of the whole exercise, when you think back at it, was the time on the runway after we’d stopped. Because we were very concerned and conscious of evacuating the aircraft using slides. We had 433 passengers onboard, we had elderly, we had wheelchair passengers, so the moment you start evacuating, you are going to start injuring people. So a lot of discussion was had on the flight deck about where was the safest place for the passengers? We’ve got a situation where there is fuel, hot brakes and an engine that we can’t shut down. And really the safest place was onboard the aircraft until such time as things changed. So we had the cabin crew with an alert phase the whole time through ready to evacuate, open doors, inflate slides at any moment. As time went by, that danger abated and, thankfully, we were lucky enough to get everybody off very calmly and very methodically through one set of stairs.
I recommend reading the full article which includes iPhone photographs of the cockpit instruments at the time of the failure and the crew’s view of the damage from the window.
Meanwhile, Ulf Waschbusch, who twittered the incident and posted photographs within a few hours of the landing, has booked a new flight with Qantas on the Airbus 380 for Chinese New Year 2011. Lets hope he makes it this time.