Qantas A380 uncontained #2 engine failure
Engine containment, at least under the USA FARs, is certified under FAR Part 33, with tests for turbine containment under FAR part 33.94.
This incident aside, the biggest threat to the industry is if the certification status of the engine is called into question.
FAA Advisory Circular 33-5
Note: It's an old one, from 1990
(My bold)
This incident aside, the biggest threat to the industry is if the certification status of the engine is called into question.
FAA Advisory Circular 33-5
Note: It's an old one, from 1990
c. Engine Tests.
(1) Engine Configuration, The engine used for the containment and unbalance tests must meet the type design for those items deemed influential to the test results. Influential items include, but are not limited to, case thickness, retention of external components, blade design, rotor structure, and rotor support structure. A typical aircraft inlet and typical aircraft exhaust nozzle/ducting, or equivalent (i.e., having the same attachment loads and reactions which influence engine case deflections, containment capability, and engine vibratory response), should be used,
(2) Conditions. The engine may be tested at nominal sea e level conditions, and:
(i) The critical blade should be released at the maximum permissible rpm with the engine rotor and static structure at the worst associated operating temperatures and stresses, or at any other realistic combination of rpm, temperature, and stress agreed to be more critical.
(ii) High speed photography and witness shields are recommended as means of determining the trajectories and energy levels of fragments that might be ejected out the engine air inlet or exhaust, or that might be released through the wall(s) of the engine casing. Any fragment(s) penetrating and escaping through the engine casing (including any containment wrapping that is part of the engine type design) will normally be cause for failing the test. Even if the penetrating fragments have low retained kinetic energy (after exiting), the engine's containment capability must be considered extremely marginal. The energy levels and trajectories of any fragments exiting the inlet or exhaust should be included in the engine installation manual for consideration by the airframe engineers.
(iii) For some engine type designs, it may be necessary to conduct tests which are more severe than the release of one blade. For example, a certain turbine may be designed to prevent disk burst, upon loss of output shaft load, by shedding its blades. Containment would be required for this condition by FAR 33.75. If the same turbine blade were found to be the most critical under FAR 33.94, and a loss of load / blade shedding test successfully demonstrated structural integrity, it would not be necessary to perform the 33.94 test for the turbine because the demonstrated kinetic energy for penetration and unbalance loads would exceed the FAR 33.94 requirements.
(iv) Following release of the critical blade, no engine control may be adjusted by the operator for at least 15 seconds after indication of excessive vibration or other evidence that would be available to the pilot, in order to simulate crew recognition and reaction time and determine the short term effects of operation with this unbalance.
(3) Test Results. The engine is acceptable if:
(i) At completion of the test, the damage resulting from a critical rotor blade failure is contained by the engine structure, and
(ii) The resultant loads do not cause: distortion of the engine casing, separation of case flanges, rotor unstacking, or other damage, if any of the foregoing would result in a hazardous condition for a typical installation; fire (external or internal); or failure of the engine mounting attachments; and
(iii) Either the engine continues to run for at least 15 seconds after indication of excessive vibration or other evidence that wpuld be available to the pilot, and then can be successfully shut down; or the resulting engine damage induces a self-shutdown anytime after initial blade release.
(1) Engine Configuration, The engine used for the containment and unbalance tests must meet the type design for those items deemed influential to the test results. Influential items include, but are not limited to, case thickness, retention of external components, blade design, rotor structure, and rotor support structure. A typical aircraft inlet and typical aircraft exhaust nozzle/ducting, or equivalent (i.e., having the same attachment loads and reactions which influence engine case deflections, containment capability, and engine vibratory response), should be used,
(2) Conditions. The engine may be tested at nominal sea e level conditions, and:
(i) The critical blade should be released at the maximum permissible rpm with the engine rotor and static structure at the worst associated operating temperatures and stresses, or at any other realistic combination of rpm, temperature, and stress agreed to be more critical.
(ii) High speed photography and witness shields are recommended as means of determining the trajectories and energy levels of fragments that might be ejected out the engine air inlet or exhaust, or that might be released through the wall(s) of the engine casing. Any fragment(s) penetrating and escaping through the engine casing (including any containment wrapping that is part of the engine type design) will normally be cause for failing the test. Even if the penetrating fragments have low retained kinetic energy (after exiting), the engine's containment capability must be considered extremely marginal. The energy levels and trajectories of any fragments exiting the inlet or exhaust should be included in the engine installation manual for consideration by the airframe engineers.
(iii) For some engine type designs, it may be necessary to conduct tests which are more severe than the release of one blade. For example, a certain turbine may be designed to prevent disk burst, upon loss of output shaft load, by shedding its blades. Containment would be required for this condition by FAR 33.75. If the same turbine blade were found to be the most critical under FAR 33.94, and a loss of load / blade shedding test successfully demonstrated structural integrity, it would not be necessary to perform the 33.94 test for the turbine because the demonstrated kinetic energy for penetration and unbalance loads would exceed the FAR 33.94 requirements.
(iv) Following release of the critical blade, no engine control may be adjusted by the operator for at least 15 seconds after indication of excessive vibration or other evidence that would be available to the pilot, in order to simulate crew recognition and reaction time and determine the short term effects of operation with this unbalance.
(3) Test Results. The engine is acceptable if:
(i) At completion of the test, the damage resulting from a critical rotor blade failure is contained by the engine structure, and
(ii) The resultant loads do not cause: distortion of the engine casing, separation of case flanges, rotor unstacking, or other damage, if any of the foregoing would result in a hazardous condition for a typical installation; fire (external or internal); or failure of the engine mounting attachments; and
(iii) Either the engine continues to run for at least 15 seconds after indication of excessive vibration or other evidence that wpuld be available to the pilot, and then can be successfully shut down; or the resulting engine damage induces a self-shutdown anytime after initial blade release.
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Since someone took pics of the damaged wing during flight, I wonder whether these have been passed to the PIC, and (me being an aviation layman) whether these could have had any impact on his decisions?
choffmann
Not a bad idea but I suspect that with the time available it would have made sense for one of the extra/heavy pilots to leave the flightdeck and go and have a look from the Cabin windows and then report back....probably in this case the report would have something along the lines of
Since someone took pics of the damaged wing during flight, I wonder whether these have been passed to the PIC, and (being an aviation layman) whether these could have had any impact on his decisions
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Good show by the crew in what must have been a very unpleasant experience.
Yep, funny old thing, designers having burst zones outwith fuel tank areas.....
Obviously unverified photo from above-try containing that!
Yep, funny old thing, designers having burst zones outwith fuel tank areas.....
Obviously unverified photo from above-try containing that!
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BBC photo
The fourth picture in the BBC slideshow seems to show a complete cross section of the engine casing is missing. Just aft of the disembodied head of the kangaroo it looks like you can see right through to the uniform grey background of the lower surface of the wing.
BBC News - In pictures: Qantas Airbus emergency
BBC News - In pictures: Qantas Airbus emergency
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Uncontained failure
Old Fella: I think the Wikipedia definition is more precise as follows:
- A “contained” engine failure is one in which components might separate inside the engine but either remain within the engine’s cases or exit the engine through the tail pipe. This is a design feature of all engines and generally should not pose an immediate flight risk. An “uncontained” engine failure can be more serious because pieces from the engine exit the engine at high speeds in other directions, posing potential danger to the aircraft structure and persons within the plane. -
The point I was making was that failed containment is not equivalent to inadequate containment.
- A “contained” engine failure is one in which components might separate inside the engine but either remain within the engine’s cases or exit the engine through the tail pipe. This is a design feature of all engines and generally should not pose an immediate flight risk. An “uncontained” engine failure can be more serious because pieces from the engine exit the engine at high speeds in other directions, posing potential danger to the aircraft structure and persons within the plane. -
The point I was making was that failed containment is not equivalent to inadequate containment.
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only for taxiing ?
Yes, one camera is installed on VTP. But, it can be used only during taxing and below 60km/h of speed.
Are those the rules regarding camera use or is the camera actually inhibited whilst airborne and/or above 60km/h?
From previous flights in the 380, the camera is available to all on board from push back to arrival, and everything in between.
As a passenger booked tomorrow on QF11, I'm watching this whole thing to see what happens when I get to check in.
From previous flights in the 380, the camera is available to all on board from push back to arrival, and everything in between.
As a passenger booked tomorrow on QF11, I'm watching this whole thing to see what happens when I get to check in.
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It seems to be used free fall down !!
As you see the picture, all landing gear doors still opened even L/G down.
that means could be empty of green hydraulic fluid due to engine burst. As you know A380 hydraulic system powered by 5000p.s.i. so, if engine driven pump line damaged then just takes few minutes to make empty reservoir.
Nose and wing L/G system operated by green hydraulic system and main L/G operated by Yellow system.
that means could be empty of green hydraulic fluid due to engine burst. As you know A380 hydraulic system powered by 5000p.s.i. so, if engine driven pump line damaged then just takes few minutes to make empty reservoir.
Nose and wing L/G system operated by green hydraulic system and main L/G operated by Yellow system.
Last edited by SSDR1999; 4th Nov 2010 at 10:56.
Sky news has just shown passenger footage, they filmed the ife screen which was showing the outside camera. Showed the a/c landing back.
It was dark outside, once the a/c touched down there seemed to be a lot of sparks, which were not there before.
They were very close into the fuselage, first thought was landing gear or maybe others parts now in contact with the runway!!
It was dark outside, once the a/c touched down there seemed to be a lot of sparks, which were not there before.
They were very close into the fuselage, first thought was landing gear or maybe others parts now in contact with the runway!!
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there are two camera system installed!!
one camera system called ETAC (External & Taxing Aid Camera) the other system called LCS (Landscape Camera System) for moving airshow. it is totally separated. if you fly with A380 then ask flight crew. cabin crew doesn't know the system well.
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BBC photo
The fourth picture in the BBC slideshow seems to show a complete cross section of the engine casing is missing. Just aft of the disembodied head of the kangaroo it looks like you can see right through to the uniform grey background of the lower surface of the wing.
BBC News - In pictures: Qantas Airbus emergency
Yes - it appears that way to me too.
The fourth picture in the BBC slideshow seems to show a complete cross section of the engine casing is missing. Just aft of the disembodied head of the kangaroo it looks like you can see right through to the uniform grey background of the lower surface of the wing.
BBC News - In pictures: Qantas Airbus emergency
Yes - it appears that way to me too.
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Reminds me of the BA 777 excess fuel burn also ex SIN.
It was due to this........
It was due to this........
Forewarned is Forearmed
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Looking at pictures 2 & 4 from the BBC you can clearly see the cowling in picture 2 is fully intact (qantas logo visible) however after the application of foam it has become fragmented, (picture 4) so it's possible this was due in part to the firefighting operation on the ground and may be the pressure and thermal stress on contact with the foam jet being applied.
Foam into an engine thats still hot can be exciting no wonder there was cowling bits being picked up afterwards on the ground and collected into a pile.
Foam into an engine thats still hot can be exciting no wonder there was cowling bits being picked up afterwards on the ground and collected into a pile.
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Containment
Firstfloor. Without getting into the semantics, I agree that the Wikepedia definition is more precise, however Wikepedia is a public forum which may be edited by the public and therefore not an authoritative source. You expressed concern about the use of the word "uncontained". As a general expression, an uncontained failure is one where a rotating member is able to penetrate the engine casing and be radiated outward from the engine assembly potentially causing further damage or injury. Engine manufacturers are indeed required to, as far as is possible, design engine casings to prevent such penetrations, which they usually do in the case of blade shedding. Disc failure is another matter and will often result in penetration. As I said, QF32 has clearly suffered an uncontained failure and the use of the term in this case is wholly justified in my opinion.
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Engine containment, at least under the USA FARs, is certified under FAR Part 33, with tests for turbine containment under FAR part 33.94. This incident aside, the biggest threat to the industry is if the certification status of the engine is called into question.
Reminds me of the BA 777 excess fuel burn also ex SIN.
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Admission upfront - I'm a UK national transport journalist.
I haven't seen anything here about whether ingestion of foreign objects from the runway might be a possible cause - is that a possibility or would you expect that to cause a problem immediately rather than the 10-15mins after take-off that it seems to have taken?
Thanks
I haven't seen anything here about whether ingestion of foreign objects from the runway might be a possible cause - is that a possibility or would you expect that to cause a problem immediately rather than the 10-15mins after take-off that it seems to have taken?
Thanks
Looking at pictures 2 & 4 from the BBC you can clearly see the cowling in picture 2 is fully intact (qantas logo visible) however after the application of foam it has become fragmented, (picture 4)
D.