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Seems now that they are saying the engines did respond initially and then reduced..
'Engines running' in crash plane
- Thread starter James07
- Start date
A dude at work I know used to work for British airlines.
He reckons that the fuel pumps or something failed.
Apparently the fuel pickups for the engines are at the front of the wing, at the rear are pumps or something that get fuel to the engine when the nose goes up.
He thinks those pumps most likely failed.
Cant remember exactly what he called them but it sounds plausible.
He reckons that the fuel pumps or something failed.
Apparently the fuel pickups for the engines are at the front of the wing, at the rear are pumps or something that get fuel to the engine when the nose goes up.
He thinks those pumps most likely failed.
Cant remember exactly what he called them but it sounds plausible.
There are multiple pumps in each of the tanks, so the chance of them ALL failing at the same time is unlikely....even then there is suction feed from engine driven pumps which will be fine for landing.
Hahaha what does he do at BA that makes this even mildly plausible. Hostess? Dispatcher? Ticket sales? I hope to god he's not an engineer. You think any aircraft company is dumb enough to put all the fuel pumps on the same electrical bus? I dread to think how high the climb angle would have to be to stop the pumps picking up fuel
As has been said with the engines running they would suction feed just fine.The aircraft lacked power for some reason yet unknown or unreleased it didnt throttle up, even if 4 pumps had failed raising the nose wont make a **** of difference.
Besides this has all been done in the other thread, I said in there from post one the engines hadn't failed but no one cared to listen even when the pictures clearly showed the core had ingested loads of crap.
The engines have just failed to respond to increased throttle commands. They have already said they lost EPR readings, which again has sod all to do with fuel. Even if they lost EPR the fadec has it's own sensors to revert to and if that's screwed it can revert to N1 control. Why the engine failed to do that is beyond me. I'd like to know if the crew even tried to manually hard revert the engines and if not why not.
I'm doubting both engine fadecs failed at the same time, again they are completely independant software and systems with completely independant back ups. The normal procedure when one engine has EPR failure is to revert that engine to N1 control. You then do the same with the other engine by switch selection so both engines are under the same control rather than in different configs.
I'm very intererested to see exactly how this dual failure managed to happen on an ETOPS aircraft.
The trouble with the whole reporting of this incident in the media and tv interviews is the amount of pure bull that floods out. Any **** head plane spotter all of a sudden becomes an expert. One quote from a pilot that the aircraft lossed power all of a sudden became dual engine failure, then a dark cockpit. Then before you know it this topgun pilot has landed the aircraft with no engines, no electrical power and no hydraulics.
(works for rolls royce)
To be fair to the crew, and just thinking what I would do myself in that situation, but if you loose control of the engines at 600ft then you simply don't have time to start trouble shooting what has happened and going through the QRH. You just need to keep the aircraft under control and get it landed as safely as possible.
Yeah but surely as someone that flys a boeing if you lose EPR and you revert thats the first thing your going to do? Sod a checklist that's a basic for you guys?
After all only one was flying while the other one had a kip
Yeah but surely as someone that flys a boeing if you lose EPR and you revert thats the first thing your going to do? Sod a checklist that's a basic for you guys?
After all only one was flying while the other one had a kip
Well actually I don't have any experience using EPR, the 737-800 uses N1 as the primary engine indication. I don't know what the EEC is like on the 777 but the 737 has two alternate modes that it will revert too if the normal mode fails, this happens automatically but yes you can also select it manually if needed.
Unfortunately its not as easy as just saying sod the checklist. In the heat of the moment its easy to just start podging buttons to fix the situation, but a lot of backup systems have side affects that could causes troube in the long run. Hence the checklists are there to fully understand the problem and then fix the situation in the correct sequence. but of course the first rule of flying is fly the damn aircraft!! 600ft is very low and you really need to fly the aircraft and decide where to put it etc. In this situation there WERE 3 pilots on the flightdeck so you could argue one of them should have had time to try the alternate modes whilst the other two we flying the aircraft.
Regardless of the modes the 777 and 737 revert to it's the same principle. When one mode fails and the engine reverts you have to hard select the other engine so you dont get throttle split.
If as the pilots claim they lost EPR then thats a given, you don't need a checklist for that do you? Especially not when your throttles aren't responding and your engine control warning light is on. I'm asking that out of curiousity, if your flying your NG tomorrow and you N1 fails on No1 and you cannot increase power settings surely your instant reaction is to revert both engines and check your power again rather than go for the handbook
I do find it very curious that the AIB in that latest news report says they are going to concentrate on the fuel system tank to nozzle. Yet they said the aircraft had EPR failures on both engines wasn't it?
Well the only interconnection between those failures is the fadec and the inputs it gives the fuel control unit to schedule the fuel.
Regardless of the modes the 777 and 737 revert to it's the same principle. When one mode fails and the engine reverts you have to hard select the other engine so you dont get throttle split.
If as the pilots claim they lost EPR then thats a given, you don't need a checklist for that do you? Especially not when your throttles aren't responding and your engine control warning light is on. I'm asking that out of curiousity, if your flying your NG tomorrow and you N1 fails on No1 and you cannot increase power settings surely your instant reaction is to revert both engines and check your power again rather than go for the handbook
I do find it very curious that the AIB in that latest news report says they are going to concentrate on the fuel system tank to nozzle. Yet they said the aircraft had EPR failures on both engines wasn't it?
Well the only interconnection between those failures is the fadec and the inputs it gives the fuel control unit to schedule the fuel.
Well did they have an engine control warning? If its just a loss of EPR reading then that doesn't immediately mean that the FADEC has failed, it could just be a DEU problem. Remember that the autothrottle was in as well so that would make it harder to initially realise that the engines haven't responsed as requested.
In my case on the NG well it depends obviously on the situation, at FL380 then I'd just get out the checklist since we're in no rush. At 600ft on the approach if it happened then I'd be more concerned about flying it and deciding on my options (landing short or whatever) I have to admit I most likely would ask the PM to check the EEC modes whilst I was flying. However there are also many other things that I would think could be involved. I would want to check all the engine indications to see if we had any abnormal readings and then the fuel valve positions to see if there was a valve stuck if the N1 was not responding in an expected way.
We also have to remember that it is extremely easy to sit here with hindsight and point fingers at what should have been done and what we would do. In the actual flightdeck it will have happened extremely quickly and you just have to prioritise what you do first, which is ALWAYS fly the aircraft. It really is a very interesting problem and I'm looking forward to them actually finding out what the problem was.
Whats all this talk about engines reverting and hard selecting modes? I take from what youve said that if the EPR reading/sensor fails, then one engine will automatically revert to a N1 setting, but you have to manually hard select the other engine to correspond to N1, so that you have both engines operating to the same parameter?
I only have experience with the Airbus so an explanation would be appreciated. Ta.
I only have experience with the Airbus so an explanation would be appreciated. Ta.
Soldato
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In what context do they mean 'running' anyway.
If they dont produce thrust on demand that doesnt really class as running to me.
If they dont produce thrust on demand that doesnt really class as running to me.
Soldato
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Thanks for the insight.
Combustor casing cracks and you lose a load of gas from the HP turbine reducing the fan torque to 25% of what it should be, or a fuel starvation issue causes power loss, or the ECU doesnt open the injectors.
As far as Im concerned all of those would provide the same symptons the AAIB indicate, i certainly wouldn't use the word, 'engine running' fine though
If the problem became evident at 2 miles out they had ~45 seconds until impact. By the time they realised what the problem was, say 15-20 seconds, there would have been no time to diagnose or pull out a QRH. Getting the thing down in one piece took priority.