Two 777 Engine diversions in 1 day
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Two 777 Engine diversions in 1 day
Its being reported that UA 777 flying FRA-IAD diverted to KEF (PW powered) and a CO 777 NRT-HOU (GE powered) diverted into Midway. At a rough count that makes 4 engine diversions, all while over water in 6-8 weeks [1 GE90 into Dublin 1 GE90 into Forteleeza, Brazil]
Are we seeing something here that withe the benefit of hindsight may proove to be significant, equipment ages, and not always at the rate the manufacturer expects.
Personally I have always though that the 2 engine failure statistics are missunderstood, even if it is predicted only once in 10 million flight hours
1) It is predicted to happen sometime
2) That statistic doesnt discount 3 tomorrow and no more for 100 years!
Added to this there is something I like to refer to as Shuttle Mathematics. Back in 1980 it was predicted that the shuttle system would fail once in 10,000 launches (or something like that) after challenger that figure was reduced to 1 in less than 100, ie you would lose another one before completion of the ISS. I think the actual stats now show a 2 in 107.
What this tells us is that stats are just numbers built on assumptions and that in real life experience can sometimes proove them to be worthless especially when there is pressure for the "right result" from on high.
Getting to the point, I doubt that 2 of the above diversions were in ETOPS sectors so will not even find there way into the IFE stats, further distorting the real world reilability stats. I will also thow the Trent 800 (un)contained failure at MEL into this catagory.
Whos keeping score? how are these stats arrived at? is there any independent non regulatory input. Are the regulators to close to the Airlines?
NO, Im not a journalist otherwise the thread would have been titled 600 passengers narrowly escape death in engine fire horror.
Are we seeing something here that withe the benefit of hindsight may proove to be significant, equipment ages, and not always at the rate the manufacturer expects.
Personally I have always though that the 2 engine failure statistics are missunderstood, even if it is predicted only once in 10 million flight hours
1) It is predicted to happen sometime
2) That statistic doesnt discount 3 tomorrow and no more for 100 years!
Added to this there is something I like to refer to as Shuttle Mathematics. Back in 1980 it was predicted that the shuttle system would fail once in 10,000 launches (or something like that) after challenger that figure was reduced to 1 in less than 100, ie you would lose another one before completion of the ISS. I think the actual stats now show a 2 in 107.
What this tells us is that stats are just numbers built on assumptions and that in real life experience can sometimes proove them to be worthless especially when there is pressure for the "right result" from on high.
Getting to the point, I doubt that 2 of the above diversions were in ETOPS sectors so will not even find there way into the IFE stats, further distorting the real world reilability stats. I will also thow the Trent 800 (un)contained failure at MEL into this catagory.
Whos keeping score? how are these stats arrived at? is there any independent non regulatory input. Are the regulators to close to the Airlines?
NO, Im not a journalist otherwise the thread would have been titled 600 passengers narrowly escape death in engine fire horror.
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A Related Question
I may have got this wrong, however, as I understand it if you shutdown an engine for whatever reason, but do so outside the ETOPS portion of a flight, that does not count in the statistics?
If so, can someone please explain how on earth "they" came up with that idea? Technically, "you" could shut down umpteen donks outside the ETOPS areas, and yet it would have zero effect, certification wise, on "your" ability to continue operating ETOPS.
If so, can someone please explain how on earth "they" came up with that idea? Technically, "you" could shut down umpteen donks outside the ETOPS areas, and yet it would have zero effect, certification wise, on "your" ability to continue operating ETOPS.
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Two 777 Engine Diversions in 1 Day
Anyone fancy a wager of a few shillings? My '99 prediction that pax would get their feet wet within 5 years still stands... jeez, hope I'm proven wrong. bm
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wonder what the RAF and USAF will make of this...
both about to go to two engined Jet tankers .....
Bad enough with 350 pax...
but pretty horrendous if you are also towing 6 chicks (fighters)
both about to go to two engined Jet tankers .....
Bad enough with 350 pax...
but pretty horrendous if you are also towing 6 chicks (fighters)
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Not entirely sure of your point, Bagso, why would a failure to a twin be any worse than a failure to a quad or trijet with fighters (or anything else) refuelling? Apart from them getting offside PDQ, I can't really imagine anything more sinister with just the two powerplants.
Regards, BGPM.
Regards, BGPM.
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Being a Maint. Engineer for along time I once asked a 757 Captain did he ever lose an engine during take off ? His answer was yes, and added that using the one engine power settings actually had him climbing and speeding thereby he reduced power.
Knowing this about our new generation engines I have the utmost confidence in their power abilities.
Knowing this about our new generation engines I have the utmost confidence in their power abilities.
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There seems to be basic mis-understanding on ETOPS statistics.
An inflight shutdown in any phase of flight becomes part of the ETOPS statistics used to determine the suitability of an engine/airframe for ETOPS operation.
Futhermore, it doesn't even need to be on an ETOPS airplane. A CFM56 shutdown on a non-ETOPS 737 becomes part of the CFM56/737 database used to determine CFM56/737 ETOPS eligibility.
Engine shutdown rates are monitored very closely by national certification agencies.
There have been instances where national authorities have removed ETOPS approval for their national carrier when the carrier's shutdown rate crept above the shutdown rate requirement.
This wasn't quite right as the shutdown rate requirement is supposed to be based on the world fleet data.
Kind of reminds you of Lake Woebegon where all of the children are supposed to be above average.
An inflight shutdown in any phase of flight becomes part of the ETOPS statistics used to determine the suitability of an engine/airframe for ETOPS operation.
Futhermore, it doesn't even need to be on an ETOPS airplane. A CFM56 shutdown on a non-ETOPS 737 becomes part of the CFM56/737 database used to determine CFM56/737 ETOPS eligibility.
Engine shutdown rates are monitored very closely by national certification agencies.
There have been instances where national authorities have removed ETOPS approval for their national carrier when the carrier's shutdown rate crept above the shutdown rate requirement.
This wasn't quite right as the shutdown rate requirement is supposed to be based on the world fleet data.
Kind of reminds you of Lake Woebegon where all of the children are supposed to be above average.
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As far as I understand firebird, the 757 had and still has the best power-to-weight ration of any airliner ever built!
Unless things have changed , this may still be true, its a v powerful bit of kit, but I think a fully laden 777 is gonna be a darn sight heavier
The bigger they are, the harder they fall it is said, - anyone remember the (Continental?) 747 at gatwick that knocked the top of a house off after losing just one engine (25%loss) on take-off???
Unless things have changed , this may still be true, its a v powerful bit of kit, but I think a fully laden 777 is gonna be a darn sight heavier
The bigger they are, the harder they fall it is said, - anyone remember the (Continental?) 747 at gatwick that knocked the top of a house off after losing just one engine (25%loss) on take-off???
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flight sim boy: wrote
No not really, i'm just used to reading the fine print. As I understand it debris were thrown from the engine, passed under the aircraft and impacted the remaining servicabe unit. And here it is in black and white.
I dont call that contained!
Lets think about this, on a take off run 1 engine was lost and the debris impacted the other, it didnt damage it admittedley but we are talking about the begining of the run. At or about rotation speed everything has much more energy and in a situation where you have to "go" and the other unit must be able to give you 100% there is (appears to be) a risk of debris impacting and at least passing through an engine rated and running close to 90,000 lb thrust..... Can anyone see the problem here? Whatever your TOW this is a nightmare scenario.
While on the face it seems to be a standard blade out, no drama, event looking a little closer the incident seems much more serious with disasterous potential but I dont recall any regulatory authorities working through the above and asking for assurances that the second unit could not be pinged, you have to ask why
I understood that during certification it had to proved that this could not happen but it did 2 years ago.
You also have to question the sanity of Boeing going for a single powerplant supplier on all high gross weight 777's. Not only because it p1ssed off RR customers costing them order from BA amonst others but because a proven engine related mid pacific ditching could kill the program.
RTFI - According to the official ATSB report the emirates event at Melbourne was fully contained...
Do you know something they / we don't??
Do you know something they / we don't??
Failure of the RB211 Trent 892 engine as fitted to the aircraft was a result of the release of a single blade from the low-pressure compressor (fan) rotor disk. The blade release caused extensive damage to the remainder of the fan and the intake shroud, however the event was fully contained. The only escape of debris from the engine was small, low energy fragments, causing minor damage to the fuselage and the opposite engine.
Lets think about this, on a take off run 1 engine was lost and the debris impacted the other, it didnt damage it admittedley but we are talking about the begining of the run. At or about rotation speed everything has much more energy and in a situation where you have to "go" and the other unit must be able to give you 100% there is (appears to be) a risk of debris impacting and at least passing through an engine rated and running close to 90,000 lb thrust..... Can anyone see the problem here? Whatever your TOW this is a nightmare scenario.
While on the face it seems to be a standard blade out, no drama, event looking a little closer the incident seems much more serious with disasterous potential but I dont recall any regulatory authorities working through the above and asking for assurances that the second unit could not be pinged, you have to ask why
I understood that during certification it had to proved that this could not happen but it did 2 years ago.
You also have to question the sanity of Boeing going for a single powerplant supplier on all high gross weight 777's. Not only because it p1ssed off RR customers costing them order from BA amonst others but because a proven engine related mid pacific ditching could kill the program.
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ETOPS
Yes reasonable, for twins considering the problems involved.
Having said this, do think that anything exceeding 180 minutes is stretching it to the extreme.
Having been a 3/4 engine driver for a very long time, including trans-Pacific (where runways are not exactly expansive), suspect that if 240 minutes becomes the norm, then a wet footprint can be expected.
And also expect....the results ain't gonna be pretty.
Yes reasonable, for twins considering the problems involved.
Having said this, do think that anything exceeding 180 minutes is stretching it to the extreme.
Having been a 3/4 engine driver for a very long time, including trans-Pacific (where runways are not exactly expansive), suspect that if 240 minutes becomes the norm, then a wet footprint can be expected.
And also expect....the results ain't gonna be pretty.
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The CO ( exPeople Express) 747 at LGW had to have 2 engines changed before its return to USA.....
If I remember right .....One engine failed at T/O , another surged constantly......believe that a pax had a video just after T/O of the No. 4 with plenty of flames from the jet pipe and the ground alarmingly close.....
Max weight, Max X-wind, ........also seem to recall that flight was to Maimi, but was alway flight planned to Washington, as it could always make that distance, and then if the gods were favourable it would refile during the flight to Maimi.
Anyone confirm this ?
Any practices like this still continue ??
If I remember right .....One engine failed at T/O , another surged constantly......believe that a pax had a video just after T/O of the No. 4 with plenty of flames from the jet pipe and the ground alarmingly close.....
Max weight, Max X-wind, ........also seem to recall that flight was to Maimi, but was alway flight planned to Washington, as it could always make that distance, and then if the gods were favourable it would refile during the flight to Maimi.
Anyone confirm this ?
Any practices like this still continue ??