Just to be a tad more inclusive in this postulation, also add crew actions as a contributing/causal factor in some way that is not annunciated (time captured) on the recorders. Remember that some recorders don't latch everytime a bit or byte changes.

This thread needs some guidance and direction again. Come back PBL and bsieker - what should be discussed?

Well here's a potentially new twist, as I haven't read all the posts maybe it's been mentioned B4.

Mate of mine who flys the 777 made the same arrival into Heathrow from LAM a couple of hours B4 the stricken A/C. Now, aficionados correct me if I'm wrong, the 777 has both auto engine A/ice and auto Airframe A/ice systems. My mate had obviously seen operation of the engine a\ice system many times but never the auto airframe a\ice. That morning, apparently, the icing in the LAM hold was so severe that for the first time that he had seen the auto airframe a\ice system operated. He was so surprised that the fact was mentioned to ATC and later the ATIS was updated to mention severe icing.
He also mentioned that those huge Trents can have a problem with ''core icing'' but didn't elucidate on the matter!
Could severe icing during potentially a textbook CDA approach from the hold with the throttles almost closed right down to 600' produce a lack of response from the Trents as seen on the BA A/C?

I commend this question to the house!

Take care

mark exclamation,

I don't know if there's really a new twist.

Core icing in high-bypass turbofan engines has lately been the subject of some discussion, such as this PPRuNe thread, discussing a Wall Street Journal article, as well as a small article in the German Spiegel weekly magazine. But what I've read, the symptoms are usually flameouts, almost always with a quick relight.

From what I gather one of the problems is that core-icing at cruise altitudes has for a long time been thought impossible, but has recently been established as a likely cause for flameouts at altitude. The icing is apparently caused by very small ice particles and/or supercooled droplets.

This video mentions that drops above a certain size are normally deflected outward by the fan blades and do not enter the engine core. The very small size of the droplets/crystals in question may facilitate their entering the compressor and accumulating there under certain conditions, which, as of now, seem to be unknown. When larger chunks of that ice break free they may melt in the combustion chamber (or the later, hotter compressor stages) and cause a flameout, or even damage turbine blades.

Another thing that's peculiar about this form of ice accretion in the engine is that it may happen in conditions, under which the airframe does not suffer from ice accumulation.

To get back to the topic, in the case of BA038 there was no flameout, but "only" a failure to sustain a higher than "somewhat above flight idle" thrust. I'm still uncertain if there may be a connection. It seems unlikely, but then again, so does every possible explanation so far.


Bernd

In BA that would not have been a 'textbook CDA'. It has been covered numerous times before ad nauseum.

Core icing is a known issue in certain defined conditions on the ground with Trent B777 engines and we have procedures to follow when it is a possibility.

In the air we have no knowledge or requirement for any procedures relating to core icing. As has been mentioned, it has now been discovered that it is possible in certain conditions but we have received no official communication on the subject.

That bloody Carb Ice
 

ExclamationMark,
.......As a scenario it fits.
As I read it , core Icing when taxying in foggy conditions did not always lead to flameouts while running at low speed.If the engines had got any sort of ice in them you can bet your boots they would not be able to run properly or efficiently.Acceleration from idle revs would be bound to be somewhat reduced
.......This is the first I heard about severe icing in the LAM holding pattern before Final approach. Who says this? Whats his qualification to make the observation? Is it confirmable.Surely the AAIB interrogation would would have shown this up early on.

Looks like the investigation is focusing on slush or ice in the fuel system as the root cause of the problem. Is there a redesign of the oil coolers in the near future?

The article follows....

Re-Evaluating Long, Cold Flights

Crash May Prompt
New Safety Rules
For Boeing's 777
By ANDY PASZTOR
April 25, 2008; Page B2

Prompted by the crash landing of a British Airways jetliner near London earlier this year, air-safety investigators are moving to recommend heightened cold-temperature safeguards for Boeing 777 aircraft flying long polar routes, according to people familiar with the details.
In a few weeks, these people said, investigators are likely to warn operators and pilots of Boeing Co.'s long-haul 777 models to take extra precautions when monitoring fuel temperatures on a growing number of extended flights over the North Pole. If temperatures creep too low, pilots can descend to warmer air or speed up to increase the heat generated by air friction against the plane's skin.
• The News: Investigators are moving to recommend cold-temperature safeguards for Boeing 777s on polar routes.
• Background: Slush or ice build-up in a British Airways 777 fuel system may have led to a Jan. 17 accident at London's Heathrow Airport.
• Outlook: Operational warnings or recommendations could come in the weeks ahead.


"It's a possibility" that such operational warnings or recommendations will be issued within the next few weeks, said David King, chief investigator for Britain's Air Accidents Investigation Branch, or AAIB, which is in charge of the probe. In an interview Thursday, Mr. King said safety experts are "looking at a wide range of things" affecting fuel management and environmental conditions on polar flights.
Though some are arguing for design changes, a team of U.S. and British investigators hasn't reached a consensus on whether to recommend modifications to make the fuel systems on some Boeing 777s more resistant to unusually frigid conditions. Such a move could be seen as a public relations blow to Boeing and Rolls-Royce PLC, which supplied the engines and related hardware on the accident aircraft.
A spokesman for Rolls-Royce, which has declined to comment on the accident or the status of the investigation, said Thursday that the company "remains committed to working with the AAIB and Boeing to establish the root cause of the event" and is cooperating with other participants. British Airways, Boeing, the Federal Aviation Administration and the U.S. National Transportation Safety Board all declined to comment.
Investigators suspect that the Jan. 17 accident at London's Heathrow Airport occurred because slush or ice built up in part of the fuel system of the British Airways 777 during a long polar flight from China in unusually cold outside temperatures. As the widebody jet descended toward London, remnants of icy particles likely clogged a portion of its fuel system, starving the Rolls-Royce engines and providing minimal power despite pilot commands for more thrust.
The plane slammed down 300 yards short of the runway. All 152 aboard survived. The probe has been closely watched partly because the root cause remains elusive and complex. The accident has garnered attention because it is believed to be the first such incident involving both of a plane's engines while maneuvering at such a low altitude in more than 14 million 777 flight-hours since 1995.
Some U.S. experts have advocated changing the design of the oil cooler used on some versions of the Boeing 777 powered by Rolls-Royce engines, arguing that that is where ice or slush may have blocked proper fuel flow. Taking the unusual step of disclosing details of a pending investigations, Mr. King said: "I don't believe there is anyone on my team that would argue for a redesign" of the oil cooler.
Investigators have ruled out engine or computer malfunctions, and pilot slip-ups, as well as systemic problems with fuel-tank design, fuel pumps or temperature sensors, according to people familiar with the details.
Write to Andy Pasztor at [email protected]

F111D says in part.....
Quote "Looks like the investigation is focusing on slush or ice in the fuel system as the root cause of the problem. Is there a redesign of the oil coolers in the near future?

The article follows"....End Quote.

Aviate quotes from the said article....
"Taking the unusual step of disclosing details of a pending investigations, Mr. King said: "I don't believe there is anyone on my team that would argue for a redesign" of the oil cooler."

Smoke and mirrors and speculative journalism from Andy Pasztor?

The aircraft "slammed down", but I just love that word "jetliner":)

Perhaps one of the older generation:

Wiki quote "Also developed in 1949 was the Avro Jetliner, and although it never reached production, the term jetliner caught on as a generic term for all passenger jet aircraft"

The only other time I've heard it used is in an Arlo Guthrie song (?).

VnV

Ater my retirement from a legacy carrier on 747 aircraft equiped with RB211-524 engines, I operated a 747-100F with JT9D engines which had engine de-icing systems providing controlled heating of the fuel when manually activated if the fuel temperature indicator showed fuel temperature at the engine to be 0c or below, or when the fuel icing light illuminated. Heating was limited to a one minute heater operation or two minutes if No.1 tank temeperature was below -40c, for every 30 minute cycle. Kept the flight engineer pretty busy. The fuel heater was situated between the boost and high pressure stages of the engine driven fuel pump and heating was provided by 15th stage bleed air. As far as I know, fuel heating is automatic on all modern high performance powerplants but the problem of fuel icing is old hat and well known.

Operational changes ahead ... and redesigns!
 

Warning: I'm non-professional; not crew, not engineer - just scientist guest and thanks.

Hello again,
Referring to the Andy Pasztor article in WSJ, post 908, and my post 751, 'What if no proof of cause - what does the AAIB do?' when I wrote:
"I've been wondering what would the AAIB do if they could not demonstrate to a high probability the cause of the accident. If, for example, the AAIB were convinced, but could not prove, that the fuel quality had been lowered by cold-soaking for an extended period of time and that this had lead, in some unknown way, to the accident, what would they do?

Presumably the AAIB would operate on the precautionary principle.
Might they:
1) Recommend/demand/regulate the avoidance of extended flight-time in very cold air masses;
2) Demand that if aircraft had experienced extended flight-time in very cold air masses then they must
loiter for some time in warmer air before descending for landing?"

I'm going to assume David King of AAIB is fairly certain that fuel degradation due to cold-soaking for extended periods of time is the root cause of the accident and that his quotes in the above article are accurate.

Then David King would seem to be trying to gather support in advance for a set of operational recommendations that he knows, or suspects, the industry will resist. Presumably he is not acting alone and, hopefully, will already have significant political support, albeit presently hidden below
the palisade.

Fact is that demonstrating by experimentation that fuel degradation was the result of operating conditions will take years. In the meantime, the industry should soberly reflect on the continuing lives of 152 souls and consider the accident a clear warning that, as has been the case so many times previously, and in most arenas of human endevour, we don't know it all!

So I think that in a few weeks there will be recommendations from the AAIB (and others) that operations in 'polar regions' must change.

And my predictions for the years ahead:
1) Fuel stratification will, by experimentation, be shown to be the direct cause of the accident (see post 241).
2) Aircraft will have systems (probably laser based) to detect ice/sludge etc. in fuel tanks. These may be retro-fitted to aircraft that fly ETOPS.
3) New fuel heating systems will be mandated for all new aircraft designs, that is, the fuel will be heated in the tanks and will not rely any longer on the downstream heat exchange systems returning the fuel to a non-degraded state.

Regards, Tanimbar

I think so.
Obvious contradiction with initial report where fuel quality was just fine.
Any Fuel Pressure Pump EICAS message type ?
Any Fuel Filter Clog EICAS message type ?
What about an AAIB official update ... is it better to first advise Mr Pasztor ?

Yes - still
 

:D It takes a while to conjure up the necessary technical gobbledegook type spin to pad out a 1000 page report document which finally comes to the conclusion it was outa gas. :ok:

Core Icing
 

Core icing might expaln my previously expounded theory about rotating stall (which could be caused by failure of the airflow control system OR restriction into the IP compressor).

Maybe he's right; after all, whoever was dropping off the corpse of a long-dead Labour Foreign Secretary of the 1960s at LHR must have been up to something!

Lloyds RF (EMI) theory
 

Gee! And anyone who speculates on such a conclusion gets sent to the "other" list. And we get to ride on the short bus, too...

I have a feeling that if there was any genuine weight to that theory then that wouldn't be the case. As it appears, the theory has only hung around as long as it has due to an uncorroborated posting on a US pilot board with absolutely nothing backing it up.

For random background, it was David King who oversaw putting the Lockerbie 747 back together and proved exactly where the bomb was placed, so it's not like he's unknown in the US, nor is he politically tied, having been the head honcho at the AAIB since long before the current administration (to use US terminology) was in charge. From what I've read the NTSB hold him in *extremely* high esteem.

Shall we speculate or shall we challenge?
 

It would seem to me, in this instance, we should take action to invigorate the AIRB and their associates in America, Boeing and RR to come clean with it. This has gone on too long and our fellow airmen and the people they are charged with carrying are either too much at risk or not to be bothered. Make your thougts known to those who might encourage the blokes along.

Those of us long retired can be a nusiance among them. On the other hand, if the gentlemen on the line begin to growl, maybe ...........

I have sent a number of messages to the US FAA, the NTSB and Boeing. Amazingly, in three weeks, not one of them has responded. The world wonders.............................


Tom

Didn't all the geopolitical horse trading with that rogue regime of Muamar Ghadaffi make that Lockerbie tragedy seem a bit " convenient " and ' aha-ish "?

The icing and slush scenario is indeed plausible but to have it happened to both engines ( albeit with some seconds of time lag ) was a little bit too coincidental. Was there any indication that the auto engine anti ice had been activated on that BA038 flight?

The post by F111D (re: Andy Pasztor article) does support those of us who favour the slush/icing theory for the crash.

It is a theory that goes a long way to explain the following:

* near simultaneous loss of power in both engines. (a critical factor that all theories need to explain and a severe limitation on most.)
* slight differences in conditions in each fuel tank can explain the slight difference (seconds) in response.
* why the engines responded properly to start with then dropped down to a thrust level somewhat above flight idle shortly afterwards.
* fuel pump cavitation (from slush retarding fuel suction)
* minimal remaining evidence (remaining slush would melt)
* if slush was mostly sucked out of the system prior to the crash, it would also explain why the fuel would test within specifications. (Jet A-1 Chinese equivalent Jet Fuel #3) It probably wouldn't have taken much water content in the fuel to cause problems if it was in the right location. All (or most) of the water would have frozen out at the temperatures in the fuel tanks and migrated to where it could cause grief.

I don't see any notes in the last AAIB update about EICAS warnings (fuel pressure pump or fuel filter clogged) as noted by CONF iture, although it isn't clear that they would invalidate the theory if they didn't (or did) occur. The AAIB report notes that the high pressure fuel filters were clean after the incident.

It also doesn't rule out there being other factors involved, but it explains events reasonably well without them.

I think that the reason the next update is taking so long is that the incident has a number of subtle causes. AAIB needs to make very sure they have it right. If this theory is correct or mostly correct it could cause huge changes in procedures in long haul flights in extreme cold weather as well as have the potential for other operational or aircraft design changes. If the cause was simple and straightforward, the AAIB would most likely have let us know already.

Quoting AAIB Special Bulletin 1/2008:
 

"- Both engine low pressure fuel filters were clean.
- The fuel oil heat exchangers (FOHE) in both engines were free of blockage.
- The right FOHE was clear of any debris, however the left engine FOHE had some small items of debris on its fuel inlet bulkhead.
- The high pressure filters were clean.

- A sump sample taken from the left and right main fuel tanks shortly after the accident revealed no significant quantities of water."

Although the ice/slush theory is plausible, wouldn't there have been an increased level of water content found in the fuel lines near the fuel filters, fuel oil heat exchangers or servo fuel lines? And if there was a presence of ice/slush, wouldn't some of it have been collected as water in the main tank sumps? Some of the ice/slush, being a solid and heavier than fuel, would likely have found its way to the lowest points in the tanks.

The Andy Pasztor article reminds me of the "industry insider" who claimed for example on jan. 30th [quote] "the fuel crossfeed valve switches were found in the open position and only one valve was open" [unquote]. The AAIB report, published on feb. 18th, explicitly mentioned that both valves indicated that they were closed and they had not been operated during the flight.



Green-dot

Need not be H20 that caused problem
 

Many posts comment on ice/slush as being the primary cause of fuel degradation but this need not be so. The fuel is complex and a prolonged cold-soaking, in a moderately high frequency environment, might produce physical amalgams and/or emulsion of hydrocarbon + H20 and any other material included in the fuel. Give these oddities a few more hours to develop and they may change their physical characteristics again.

Put those oddities back into a temperate climate (Heathrow ground level) and they might disappear altogether, leaving no clue to there former presence.

Difficult to investigate. And, if the AAIB cannot find another cause it might now have to show that the fuel was, or was not, the cause of the accident. I don't think it can leave doubt.


regards, Tanimbar

Xfeeds operated or not? what says FDR?
 

#923 Greendot
....There was a strange re-edit of a lot of posts which became redated 18Feb, so I cant find full versions of the original relevant posts now.
....It had been stated that a "The Captain now recollected operating X feeds" (Plural),with the implication that it was after the engines failed to respond. It was also stated that (I personally cant remember which )
....Either they were set to, open and one was not fully open-
....Or they were set to closed and one was not fully closed.
.... In any case I read that one xfeed finished in a part way position...............So???

Wilyflier

That information didn't come from the AAIB; it was on another aviation site, and it was an 'informed sources have said' kind of report.

It seemed to contradict the subsequent interim report from the AAIB in several ways, so I think it just served to confuse the issue.

No reason to believe that the pilots opened x-feeds, per the AAIB.

Mat Tonkang:
This is off-topic, but just to confirm - the AAIB's work at Lockerbie was purely technical, determining the break-up sequence from the point the bomb went off. It had no jurisdiction on the who, only the how.

Back on topic, the AAIB *is* a branch of the Civil Service, but it is a very different beast to the NTSB. What they do have in common is that they are both politically neutral, so if EMI had not been ruled out, or at least downgraded, they would have mentioned it as a possible contributing factor in the interim reports regardless of where it came from. Their remit is to figure out what happened - nothing more - and by all accounts they are extremely good at it and are world-respected as a result.

To wilyflier #926:

The AAIB special bulletin 1/2008 does not mention any recollection of the crew switching the crossfeed valves or finding one of them open or partially open.

Quoting 1/2008, page 2:

"The total fuel on board was indicating 10,500 kg, which was distributed almost equally between the left and right main fuel tanks, with a minor imbalance of about 300 kg. The crossfeed valves indicated that they were closed and they had not been operated during the flight."

This implies the AAIB has been able to confirm this from the FDR data (and likely from crew interviews) or they would not have made the statement: ". . .and they had not been operated during the flight."

Those are the officially published facts sofar regarding the crossfeed valves. No more, no less.

In light of only 300 kg imbalance between left and right main tank, it is also ruled out that one of the crossfeed valves could have been (partially) open undetected.



Green-dot

I'm not sure about that Green-dot, if crossfeed is open but fuel pumps are not switched off on one side or the other, each wing tank will still feed its own side engine unless fuel pressure is somehow stronger on one side.

If I'm correct one crossfeed will automatically open under a certain type of electrical failure ... !?



... You mentioned that, I mentioned that, it would be nice to know exactly when the APU flap started to move ?

To CONF iture:

You are correct, with all boost pumps running in both main tanks there would be no crossfeed if a crossfeed valve were to be in the open position. However, if only the APU is running (with boost pumps off on the overhead panel) there would be a crossfeed. But that would be a temporary condition.

An undetected open position can be ruled out. First of all, an open crossfeed valve in disagree with the pushbutton would generate a valve light in the pushbutton and EICAS advisory and status messages would be displayed (after 10 seconds). No way it would go unnoticed by the crew.

I am not aware of any automatic crossfeed valve selection. To my knowledge crossfeed valve operation is a manual selection only.

With regards to when the APU flap (assuming you mean the APU door) started to move. That may be a tougher nut to crack. I can think of a few possible scenarios:

- APU started by the crew: Not mentioned by the AAIB in their report S1/2008. Could very well have been the case even if not mentioned by the AAIB.

- APU autostart: For that to happen, power would have to have been removed from left and right transfer buses in flight. That did not happen because the ram air turbine (RAT) would have automatically extended during an APU autostart. There is photographic evidence the RAT did not extend in flight. It extended after impact on the ground.

- APU door open due to other causal factors: Answer to this will have to wait for the final report. This is where several holes in the swiss cheese would have had to line up before a failure of this nature could occur.
As discussed before, i can think of a possible (but very unlikely) scenario where the APU fuel shut off valve control relay could have been affected. The same scenario would have affected the spar valve control relays. Temporary loss of power to the 28v dc hot battery bus, making both the spar valve- and APU fuel s/o vlv control relays susceptible to EMI reverse logic. If (i stress if) EMI was present it could have caused the spar valve control relays to close and the APU fuel s/o vlv relay to open, possibly latched in that position when power was restored until the EMI source disappeared, returning the system to a normal logic condition. The effects would be:

* Closing (or partially closing) of the spar valves restricts fuel flow to the engines.

* Opening the APU fuel s/o vlv control relay, instructing the APU fuel shutoff valve to open, may have triggered a signal to ELMS to open the APU door?

Ready to be flamed . . . .but . . . "when you have eliminated the impossible, whatever remains, however improbable, must be the truth", Sherlock Holmes used to say.


Green-dot

greendot:

How?

Please provide a plausible scenario to drive the relatively high current DC components involved, via spurious radio signals, keep them engaged, and then release them when the radio signal is removed. I won't ask you to explain the presence or strength of said signal, merely to describe the electrical activity of the aircraft systems responding, esp why other systems were apparently completely unaffected, only the fuel control.

I believe it is time to take the strop to Occam's Razor.

http://img117.imageshack.us/img117/8...steninggz4.gif

http://img329.imageshack.us/img329/3...rd01lx1.th.jpg
http://www.airmech.co.uk/forums/showthread.php?t=3650


This gives a good overview and history. CAUTION: link to PDF file:
http://www3.verticalgateway.com/port...s/hirfnprm.pdf

Link to FAA Final rule on HIRF certification as of Feb 2008:
http://rgl.faa.gov/Regulatory_and_Gu...E?OpenDocument

OK, just assuming slushy fuel was the cause, one would think that tests would be carried out with a jet engine and fuel that had been purposely cooled to a state of slushiness. Anyone head of any such tests being performed?

soem dood:

Thanks for the links.

That is what i wondered years ago as well, at a time when we were confronted with uncommanded closing of main fuel shutoff valves (MFSOV), also a 28v dc system but on a different aircraft type. At the time only the valve was affected, no other 28 v dc system components. Regarding a scenario: EMI does not necessarily imply an external source, in this case it was generated in the connector itself.

Something to add to the history:
http://www.corrdefense.org/CorrDefen...df/feature.pdf

and:
http://www.dtic.mil/ndia/2001systems/horne.pdf



With regards to G-YMMM: without the data it remains a theory, nothing more. I do not intend to twist facts to suit theories, it is beter to twist theories to suit facts.

But since i have had first hand experience with a similar issue (as the above links explain), first time it happened it was also thought an impossible scenario, but happen it did.



Green-dot

So it could well be an only Airbus thing, which does not apply to 777, when all AC bus fail, one single fuel pump remains powered and therefore crossfeed valve automatically opens ?

Regarding the ice build-up fuel scenario, I’m very septic that the same conditions develop at the almost exact same time in two separate fuel tanks, especially when one of them had almost 400 more liters than the other one.

I don’t know the oil cooler / fuel warmer architecture, but I find it surprising that the restriction occurs into the very spot where fuel should get warmer ?

Also, still no official mention if thrust has been applied after Top Of Descent but before the event and how both engines did react ?

Greendot, in line with your point that increased susceptibility can come from sources such as degradation of connector internal contact integrity, here is an interesting prior airworthiness directive on the 777:

RIN 2120-AA64 - prelim
http://www.thefederalregister.com/d....12-08-03-30338

RIN 2120-AA64 - final
http://rgl.faa.gov/Regulatory_and_Gu...3?OpenDocument

Thanks for the back story and discussion. I am nothing more than an armchair observer when it comes to air accident investigation, but I have much interest, as I am in a not-too distant line. For those that want an instant perfect answer, and want it now, I will just offer that the NTSB and/or AAIB do good work, and the truth will out, but good original work takes time. One of the most difficult cases ever was on the Boeing "soda can" rudder activation valve that brought down US Air flt 427, and it took a lot of investigation, and frankly, some related incidents (Eastwind 517, United 585) before it was figured out, but they got there. For those who have their interest whetted for following air investigations, but can't wait for the AAIB report, let me suggest any of the following as good reading, from my own bookshelf:

Normal Accidents, Perrow
The Limits of Safety, Sagan
Inviting Disaster, Chiles
Inside the Sky, Langewiesche
Mystery of Flight 427, Adair
Aircraft Investigation Analysis: Final Reports, Walters
Aircraft Safety, Krause
The Logic of Failure, Dörner
Mayday!, Wadley
Human Error, Reason
Columbia Accident Investigation Board, NASA/GPO
Safety in the Skies, Sarsfield

Fiction:
Airframe, Crichton

One of the links extolling the virtues of CPCs noted this about the F16 connectors:

Huge "no-no" using dissimilar metals in an electrical connection that you want to remain reliable. Galvanic action, and other bad things can happen. Pretty surprised to find that all contacts were not initially gold-gold on such a critical application.

As to CPC, the problem with many corrosion preventing compounds is degradation over time. It is hard to beat a good gold to gold mechanical contact. I remember we evaluated some stuff in the eighties call "Tweek" or "Stabilant 22" that was supposedly a 'contact enhancer but it was not proven to improve anything, and I notice in your other presentation, it is specifically not recommended... the water displacement properties of the CPC may be it's best feature, assuming a gas tight connection subsequently...

soem dood,


From one of the links you provided:
It seems dissimilar metals in electrical connections is/was used elsewhere as well.

Interesting book list.
Some of those are on my booklist as well. I am currently reading "Inside The Sky."

Some other noteworthy books on the subject:

Human Factors In Flight, Hawkins
Blind Trust, Nance
The Safe Airline, Ramsden
Pilot Error, Hurst

P.S. The above mentioned book titles should not be percieved as to suggest any link to the cause of this accident. They don't and are mentioned only because they explain the many factors related to accidents in general.


Green-dot

That that shall not be spoken
 

Green dot.
....Speak up in plain language then ,stop hinting.What is your inference that I and the others dont like to say?

Possible and not uncommon reason for the open APU inlet door:
I have seen it happen that the APU ilet door actuator was inoperative. In order to be able to provide APU power if neccessary, the aircraft may opearate under an MEL, with the door secured in its open state throughout the whole operation and an extra percentage of the tripfuel accounted for the aerodynamic loss. So open APU inlet does not neccessarily mean a running APU.

We were at the sim today ( 777 ), finished a bit ahead of time and figured, why not put ourselves on 27L at Heathrow, 160 kt til 4 DME, full flaps and throttle back the engines one by one at 700 ft to try to simulate what happened to BA 038.
The surprise and stress element was of course totally absent.
I disconnected the A/P, went under the G/P and ended doing a hard landing, actually more like a low level stall, just before the runway.
Very interesting experience.
I can't believe people could imagine they could / should have done something different. I was prepared and it just happened so fast I couldn't believe it.
Couple of miles back would have been very tragic.

Latest update pulished today 30 April
http://www.aaib.dft.gov.uk/cms_resou...8%20G-YMMM.pdf