Final report on CX780 accident published
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Killaroo. No - it wasn't a no brainer - duh.....
Barking mad. On the ground in an emergency situation, I would far rather risk a few injuries down the slide than having my passengers trapped on a burning or smoke filled aircraft. Just look at the video of the 737 at Naha some time ago. If they had rethought that for just a minute longer, there may have been a very different outcome. The downside risk of SERIOUS injuries during an evacuation is very small. So, no - I will not rethink my thinking on this matter.
Barking mad. On the ground in an emergency situation, I would far rather risk a few injuries down the slide than having my passengers trapped on a burning or smoke filled aircraft. Just look at the video of the 737 at Naha some time ago. If they had rethought that for just a minute longer, there may have been a very different outcome. The downside risk of SERIOUS injuries during an evacuation is very small. So, no - I will not rethink my thinking on this matter.
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Well the same flight the day before, was! Nowhere near as badly, obviously. They do seem to have discontinued use of that fuelling equipment as soon as the problem was suspected, limiting further possible problems. Maybe the vibration that happened while refuelling dislodged a lot of the spheres - many more than smooth flow would have. I remember years ago testing air filters, and just tapping them lets a lot of the trapped particles loose into the air, and having pulsed air flow really made them fly. Rather like the difference between placing a hammer on a nail, and hitting it repeatedly. It seems this is a very rare occurrance, and maybe the design of the affected parts makes them susceptible, while other engines may not have been affected as badly, or at all.
I wonder why other aircraft were not affected by the contaminated fuel.
I know that the Rolls RB211-524G/H controls on the 767 and 747-400 were very sensitive to fine particle contamination.
I thought the crew did an outstanding job. Some small details that showed some excellent skills:
1. When it became obvious that they had both engines indicating 'stall', the commander traded excess airspeed for altitude. A small detail, but an action that shows excellent situational awareness.
2. Turned off the flight director and hand flew the aircraft when appropriate.
3. Managed excess energy using 'S turns' on final.
4. Whilst hand flying under unusual circumstances, realized that he'd called for the incorrect bearing intercept for the ILS and corrected it.
A 35 year old Commander and a 37 year old F.O. that showed they weren't children of the magenta line. Nicely played.
1. When it became obvious that they had both engines indicating 'stall', the commander traded excess airspeed for altitude. A small detail, but an action that shows excellent situational awareness.
2. Turned off the flight director and hand flew the aircraft when appropriate.
3. Managed excess energy using 'S turns' on final.
4. Whilst hand flying under unusual circumstances, realized that he'd called for the incorrect bearing intercept for the ILS and corrected it.
A 35 year old Commander and a 37 year old F.O. that showed they weren't children of the magenta line. Nicely played.
Last edited by JPJP; 5th Sep 2013 at 20:38.
I know that the Rolls RB211-524G/H controls on the 767 and 747-400 were very sensitive to fine particle contamination.
It's the fuel metering concept that requires close clearances, not-too-tight and not-too-loose, just like a musical valve instrument.
Please don't open one up when not in a clean room.
Screens are fine, except when the contamination is created from a dissolved substances into a particle after it passes through the screen.
Nothing left but trust in the fuel as well as the crew.
and so are most of the new FADEC controlled engines on all model types.
It's the fuel metering concept that requires close clearances, not-too-tight and not-too-loose, just like a musical valve instrument.
It's the fuel metering concept that requires close clearances, not-too-tight and not-too-loose, just like a musical valve instrument.
OTOH I know very little about the Trent 700 - I don't even know who supplies their Fuel Metering Unit (i.e. is it the company formerly known as Lucas, or is it someone else).
I was interested to read that Airbus revised the QRH to provide a suspected fuel contamination and a fuel contamination checklist for the the 330.
I operate the 320/321 IAEs and I wondered why said aircraft was not included in this style of checklist, upon looking at ENG 1(2) FUEL CTL FAULT I think I [I]may[I] have found the reason, I shall leave it for others to determine.
Worth a look in your Abnormal checklist.
I operate the 320/321 IAEs and I wondered why said aircraft was not included in this style of checklist, upon looking at ENG 1(2) FUEL CTL FAULT I think I [I]may[I] have found the reason, I shall leave it for others to determine.
Worth a look in your Abnormal checklist.
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"During the climb, the flight crew noticed some abnormal Engine Pressure Ratio (EPR) fluctuations on No. 2 engine, with a range of approximately ± 0.015 around EPR target. No. 1 engine also had abnormal EPR fluctuations but within a narrower range."
"shortly after levelling off at FL390 (i.e. 39,000 ft AMSL at standard atmosphere conditions), Electronic Centralised Aircraft Monitoring (ECAM) message “ENG 2 CTL SYS FAULT” was annunciated. ECAM information “ENG 2 SLOW RESPONSE” was shown for crew awareness."
"The maintenance engineer (ME1) at the IOC asked the flight crew to check the responses of the engines to thrust lever movements. The flight crew advised that the EPR was fluctuating around an EPR target."
"As all engine parameters were considered normal other than the EPR fluctuations, the flight crew elected to continue the flight to Hong Kong."
"At 0316 hrs, ECAM message “ENG 2 CTL SYS FAULT” reappeared when the aircraft was levelling off at FL380. This time ECAM information “AVOID RAPID THR CHANGES” was also displayed in addition to the “ENG 2 SLOW RESPONSE”."
"The flight crew called MC again via SATCOM for further discussions. Another maintenance engineer (ME2) responded to the call and confirmed that he was aware of the earlier situation as they had been monitoring the engine parameters during the flight. The flight crew, with more concern this time, reported the ECAM message and the observed increase in EPR fluctuation (± 0.1 for No. 2 engine and ± 0.03 for No. 1 engine). The flight crew queried whether it was safe to continue the flight."
"Significant windshear was forecasted for both runways 07L and 07R."
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It's a long report, I've not read every word. I see the first maintenance engineer gave advice and based on that the crew made the decision to continue. By the time ME2 was involved VHHH was clearly the only possibility. I still haven't found any discussion - just a one liner "reasonable". Maybe no more needs to be said.
I'm curious as to the lack of any consideration or discussion in the report of the decision (however right or wrong) to have continued the flight to destination with faults showing on engines and one engine ineffective relatively early in the flight.
And the decision to continue was talked about in several parts of the report, and deemed completely safe and appropriate. That is what led me to question your insinuation that it was not.
You an I can sit here with the knowledge of "fuel contamination blockage caused by SAP spheres", but they did not have that knowledge at the time. All they had where some ECAM messages for which they followed their QRH and discussed with engineering for further insight.
I believe that we're missing the essence of the event when we start discussing should-ofs, could-ofs regarding crew actions.
The threat from the contamination is not steady state cruise but any throttle dithering that exercises the valving in the fuel control to either stick up or down or in some cases advance on its own to max thrust without response to the throttle position.
The threat from the contamination is not steady state cruise but any throttle dithering that exercises the valving in the fuel control to either stick up or down or in some cases advance on its own to max thrust without response to the throttle position.
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An interesting thread for sure but among all the comments made I'm surprised that there is almost no mention of the root cause of the incident and what can be done to prevent re-occurrence, i.e. fuel contamination.
A/P on at 1144'. Daytime departure.
Yeah. I noticed that. Perhaps the FO had been hand flying the aircraft so much he decided that some automation familiarization was in order ....
The point of the Magenta Line syndrome isn't the fact that familiarity with automation is inherently dangerous. It's the danger of a degradation of other abilities as a result of it. In this case, I think the Commander showed that there was no degradation of his ability to aviate. When 'push came to shove', he still knew what he was doing.
Child of the Magenta Line?
The F/O was previously an F18 driver then Learjet/Westwind target tow pilot prior to joining Cathay, so I don't doubt his ability to hand fly an Airbus.
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I'm surprised that there is almost no mention of the root cause of the incident and what can be done to prevent re-occurrence, i.e. fuel contamination.
The contaminants blocked the filters, and the fueling company just pumped up the pressure instead of investigating the reason for reduced flow. This pressure exceeded the inner metal structure design limits of the filtering cartridge, causing it to collapse and bulge slightly, creating more restriction.
The saltwater in the system affected the integrity of the filtering material, which then released the globules into the fuel flow. These spheres where small enough to not be detected during visual inspections, and caused FCU malfunctions after prolonged operation which allowed excessive buildups to block moving components.
There were plenty of recommendations to all parties, and the filter manufacturer improved the design of their system. Overall, I think the fault lies on the airport operator for sloppy construction practices followed by sloppy inspection and flushing of the system. The fueling operator also suffered from a bit of sloppiness in not investigating the blockage causing the pressure drop.