Wish

iTrader: (2)

What was the outcome of the BA plane that crashed at Heathrow ??
Has a reason been given yet?
Was it down to pilot error ???

jods

I heard it was fuel starvation - think it was airblocks in the feed lines.

mart360

They turned the ignition off, and the engines stopped.

Mart

nooobyscoooby

The vanes on the fuel pumps had got damaged and pumped air as well as fuel.

BBC - Search results for ba crash

Top right of page

druddle

Run out of fuel. Simple as !!

Dave

Leslie

The engines dont rely on ignition to keep them going, but auto ignition is fitted in case the engines flame out for some other reason.

Apparently there was some damage on the fuel pumps, maybe cavitation caused it, but they have not stated a positive reason yet for the lack of engine power.

Far too early to start the ever present tendency to blame it on pilot or crew error.

Les

Wurzel

iTrader: (1)

Fuel surge! he cornered to quickly

stilover

Global warming.

Everything else gets blamed on it.

Tidgy

global warming

85k payout for each passenger???? they having a larf, they should be happy to have walked away rather than being killed, money grabing *******s

Dave1980

its called climate change now

ScoobyWon't

How about this from pprune.

On the 29/02 on the french "rcoco.com" forum, one of the contributor joined to his post a report about the fuel scavenge system on the 777-300ER/777-200LR aircraft. I don't think that this (undated) report has been published here.
I believe it might be of some interest for most of you.[quote]

SUBJECT: 777-300ER/777-200LR Failure to Scavenge Fuel

/A/ Service Related Problem 777-SRP-28-0118
/B/ Fleet Team Digest Article 777-FTD-28-07002

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SUMMARY:
Note: This message contains important information relevant to flight operations and airplane dispatch, please distribute accordingly.

Several 777-300ER operators have reported intermittent occurrences of airplanes landing with as much as 2200 lbs/1000kgs/300 gallons of fuel in the center tank. Boeing theorizes that this is an indication that the fuel scavenge system has malfunctioned. A failure such as this of the fuel scavenge system reduces the range of the airplane and could potentially lead to fuel exhaustion in the event additional failures occur which require use of all planned reserve fuel. To address this concern, Boeing recommends that 777-300ER and 777-200LR operators review their fuel reserve policy to ensure adequate reserves exist for each mission.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

DESCRIPTION:

The scavenge system is designed to transfer fuel from low areas of the center wing tank to the main tanks after the override pumps are shut off. Scavenging this additional fuel from the center tank increases the fuel available for engine use. The 777-300ER and 777-200LR airplanes have incorporated scavenge system design changes intended to increase the amount of fuel scavenged and reduce the amount of trapped unusable fuel in the center tank to approximately 3 gallons. These changes included relocating the fuel scavenge inlet further inboard, while the water scavenge inlet location remained unchanged. Additionally, the fuel scavenge outlet and float valve were moved further outboard to allow fuel scavenge to be initiated earlier in flight.

Several 777 -300ER operators have reported intermittent occurrences of airplanes landing with as much as 2200 lbs/1000kgs/300 gallons of fuel in the center tank. Boeing theorizes that this is an indication that the fuel scavenge system has malfunctioned. These instances have only occurred on long routes originating from colder climates and have led to the conclusion that an excessive amount of water is entering the fuel scavenge system and is freezing during scavenge operations. Because the water scavenge inlet was not co-located with the fuel scavenge inlets it is more likely for water to be ingested in the scavenge system. Additionally, as the outlet float valve location is further outboard in the main tank than previous, the scavenged center tank fuel has more exposure to the cold soaked main fuel tank prior to reaching the scavenge discharge. Indications are that the water in the scavenge system is freezing prior to discharging in the main tank. Frozen water (or ic!
e) in the scavenge system could result in a low rate of scavenge or no fuel scavenge.

Failure of the fuel scavenge system could result in airplanes landing with as much as 2200 lbs (1000 kgs) of fuel in the center tank. During mission planning and dispatch, this fuel in the center tank was considered usable fuel. However, failure of the fuel scavenge system in flight renders this 2200 lbs (1000 kgs) of fuel as unusable. There is no indication to the flight crew that the scavenge system has failed and the fuel is unusable. Failure of the fuel scavenge system essentially reduces the range of the airplane and could potentially lead to fuel exhaustion in the event additional failures occur which require the use of all planned fuel reserves.

Boeing review has determined that the failure to completely scavenge the center tank is the result of system configuration changes unique to the 777-300ER and 777-200LR airplanes. This issue has been placed in our Service Related Problem (SRP) process for resolution and is the subject of the REF /B/ Fleet Team Digest article.


DESIRED ACTION
===============
Boeing recognizes each operator establishes its own fuel reserve policy. Some operators choose to add additional conservatism to existing regulatory fuel reserve requirements. In addition, we note that not all routes and/or operators have shown a susceptibility to this condition. This may be because of environmental conditions, individual airline water sumping policies, or different operator fuel system procedures.

Boeing suggests 777-300ER and 777-200LR operators review their operation for exposure to trapped center tank fuel and their maintenance policy related to water sumping.

We recommend operators establish a policy to monitor center tank fuel quantity upon arrival of each flight. If trapped center tank fuel above 400 lbs (200 kgs) is discovered, we recommend a further review of fuel reserve and maintenance policies as noted above.

If operators chose to address this issue by uploading additional fuel, Boeing recommends operators notify their flight crews that additional fuel has been loaded to mitigate the potential for up to 2200 lbs (1000 kgs)of unusable fuel following failure of the scavenge system.

For operators who have seen the trapped center tank fuel condition and chosen to adjust their fuel reserve policy, we recognize it may be possible for this condition to be resolved on future flights due to a change in environmental conditions or maintenance practices.. If this situation arises, we believe it appropriate to adjust fuel reserve policies to original levels provided they continue the monitoring policy on a flight by flight basis for trapped center tank fuel.

Although these failure to scavenge occurrences have only been reported on the 777-300ER, any Boeing recommendations should also be applied to the 777-200LR as it has an identical center tank fuel scavenge system.


If further information is needed regarding the subject, please contact your local Boeing Field Service Representative. If your local Field Service Representative is unavailable, you may contact the appropriate Airline Support Manager or call the BCA Operations Center at (206) 544-75



original link[/qoute]

M444GY

iTrader: (72)

it ran out of fuel . missus dad is head of traffic at heathrow airport

ScoobyWon't

I'm disappointed that Airdisaster.com have closed their forums. That was always a good source of info.

FlightMan

Christ there is some right old crap here.

Some facts.

It did not run out of fuel. There was 4 tonnes left on board, and at least 2 tonnes was spilled into the lighting pits on 27L.

The initial AAIB reports says that the engines did not respond to commanded thrust. That's not the same as "out of fuel ".

The AA 772 last week was a different issue. FDR's from BA38 and the AA aircraft have been looked at and compared and they show different data sets. Not the same issue at all. A United pilot I was talking to today said it was PROBABLY the First Officers arm, he was flying at the time, subconsciously resting on the throttles whilst operating the speed brakes. It only takes just over 1Ib of pressure to stop the throttles advancing over the autopilots command, and once the crew noticed a problem, the pilot would have removed his arm to deal with the situation,and viola, problem solved. The planes been looked at and test flown out of LAX with a AA crew, Rolls and Boeing engineers and is perfect.

A BA chap I was talking to on Monday said BA engineers believed it was a FADEC issue, ( engine computers ) but had no evidence to back that up. Both FADECs have been extensively tested, and both pass all tests.

Oh, and it certainly wasn't EMI from Gordon Browns cavalcade.

Or little green men.

ScoobyWon't

What do you think could have happened, Flightman?

Shark Man

When looking at it on a global systems scale. There are isn't much to stop a jet engine from working: In the crudest of terms; A Turbofan jet engine is basically an oil-buner with an array of fans attached to the exhaust and inlet. Once the fans are spinning and flame is lit, all it needs is a supply of fuel.

Increasing throttle, increases fuel supply; Now for whatever reason that didn't happen. In the simplest of terms all we have is Fuel, Sensors, Hardware/Software processing and Actuators. Its basic system logic: Input-->Process-->Output

Now the hard bit is systems that control the fueling have variety of subsystems, many of which offer tripple redundancy to counteract any foreseen failure modes. Be it a mechanical issue, sensing or a electronic/processing issue. Obviously it could be a combination of issues in several or more systems that have a knock on effect resulting in this sceinario.

The final possibility is the fuel itself (inferior properties, contaminatio - water etc), but it seems that has been ruled out thus far.

The complication is that this failure mode may only occur during very specific conditions; i.e with a pump worn by x amount in an aircraft of a specific design using a certain type of fuel control systems, which carrying x amount of fuel, containing x amount water, flying at x altitude, at x speed, and x temperature. And thats the tip of the iceburg. Because of that, the exact probelm may never be found.

For example the 737 had at least seven inccidents suspected to be related with the control of the rudder (and in excess of 70 reports). Four of which crash. The problem took quite some time (and a number of inccidents) before the actual cause of the rudder control issue was identified and under what specific conditions could cause the fault to occur. The defect now is reported and components have been redesigned and directives given in flight control so the problem is now belived to minimised and eventually, will be completely rectified, but it took some considerable investigation to replicate the fault. Retrofits are expected to be finished by this year (unless they have all been completed - I don't have the data) - some 12 years after the redesigned components were officially announced.

SWRTWannabe

A slight aside, but why is it that after the Concorde crash, all Concordes were grounded, whereas after these incidents, the same planes keep flying.

Was there something about the Concorde crash that indicated that it was not safe to fly, or is more a case of commercial pressure?

Not saying there are any rights and wrongs, just interested.

ScoobyWon't

Didn't they spend a bucket full of cash making sure all Concordes were protected from the same thing reoccuring?

FlightMan

I have absolutely no idea! But I'd say BA engineerings FADEC theory is as good as any.

mart360

Tongue in cheek mode on

So can you tell me if the engines didnt run out of fuel, why did they stop?

to quote a top gear phrase, did the box of electricity run out then?


the choice of failure mode is pretty limited

1) It ran out of fuel

2) the engines were turned off

3) it ran out of air

tongue in cheek mode off

Mart

FlightMan

Quote from my 18:10 post.

The initial AAIB reports says that the engines did not respond to commanded thrust. That's not the same as "out of fuel ".

They did not stop.

KiwiGTI

Is he a traffic cop?

KiwiGTI

Concordes were a luxury, taking the 777 out of service would probably destroy the aviation industry as there are so many in service.

nooobyscoooby

Ruled out.

nooobyscoooby

Too many expensive folk on a BA LHR-JFK Concorde if it crashed.

The one that did only had Jerry tourists on board so not too much to pay out.

nooobyscoooby

If your car was pulling air along with the fuel it wouldn't pick up either!

The aircraft engines were spooling [people reported how loud the jet sounded which would not have been the case if it was coming in on dead engines] but not enough fuel was being supplied / burned for them to speed up and provide the thrust when called for.

The pilots were criticised because they did not turn the fuel valves off during their emergency close down procedures immediately after the crash while they still had power available and a lot of fuel was spilled.

DaveD

iTrader: (2)

As far as I am aware, the only investigations ongoing at this time are into the fuel system (both on the aircraft and engine side of the pylon).

There was sufficient fuel in the aircraft to fuel the engines, but for some reason, fuel did not get to the engine combustors when demanded. There is evidence that suggests the aircraft / engine control systems were working properly and were carrying out actions consitent with a restricted flow of fuel to the engine.

As a result of the investigation, some questions have been raised about the design of the 777 fuel system - not fundamental flaws, but subtleties that could possibly make the system vulnerable under certain circumstances.

Some engine testing is planned in the near future to confirm some findings and to try to replicate some of the evidence seen on the crashed engines. In the longer term, I imagine the Boeing will be doing some flight testing - but this is likely to be some way off yet.

Leslie

As was said above, the engines did not stop but remained at a lower power setting than was required to get the aircraft to the runway. As also was explained-the only possible reason for that is that insufficient fuel was being supplied to the engines' burners to increase the power which was generated. Jet engine power is controlled by the amount of fuel supplied to the burners. Thus the aircraft would only be able to be landed short of the runway and the pilots acted in such an exemplary manner that they successfully saved the aircraft and the passengers from a very much worse fate.

The reason for the lack of fuel supply is yet to be resolved but there was certainly enough fuel in the aircraft's tanks.

That is all we know at the moment, tongue in cheek or not!

Les