NYC777 From United States of America, joined Jun 2004, 5155 posts, RR: 49 Posted (5 years 3 months 3 weeks 2 days 7 hours ago) and read 24761 times:
A detailed leaked investigation update on the BA 777 accident. The photos are really quite something. Wouldn't want to be sitting in Row 30 when that happened.
Excerpt:
• Ice in the fuel somehow limiting the fuel flow to the engines. A maintenance message indicating excessive water in the center tank was set during taxi on the two previous flight legs, although it cleared itself both times. The airplane was being operated in a high humidity, cold environment, conducive to ice formation.
• Small-sized contamination building up in the engine fuel systems somehow limited the fuel flow to engine. All the fuel samples have tested for contamination of larger particles (sizes outside the fuel specification). Testing has been started looking for small particles (greater than 5 microns).
Khobar From United States of America, joined Mar 2006, 2379 posts, RR: 4 Reply 1, posted (5 years 3 months 3 weeks 2 days 7 hours ago) and read 24687 times:
There are a number of interesting bits there.
"It appears that no fuel was getting to the engines."
Possible EEC issues
P30 issues "A preliminary review of the EEC data from the right engine shows erratic combustor inlet pressure (P30). A leaking P30 sense line could cause this, or the EEC receiving a higher than actual fuel flow parameter.
No loss of electrical power confirmed
QAR data is incomplete - it's missing 45 seconds, THE 45 seconds prior to impact (so much for that then)
Fuel cross-feed valves were open. Crew changed story.
APU was in autostart. Crew changed story.
Tjwgrr From United States of America, joined Mar 2000, 2297 posts, RR: 3 Reply 2, posted (5 years 3 months 3 weeks 2 days 7 hours ago) and read 24485 times:
IAD787 From United States of America, joined Jun 2005, 501 posts, RR: 45 Reply 3, posted (5 years 3 months 3 weeks 2 days 7 hours ago) and read 24409 times:
Nucsh From United States of America, joined Apr 2004, 238 posts, RR: 0 Reply 5, posted (5 years 3 months 3 weeks 2 days 7 hours ago) and read 24287 times:
Quoting From Flightblogger & the report: Preliminary data indicates that the descent rate at impact was roughly 30 ft/sec. Dynamic seat requirements that became effective at the introduction of the Model 777 series airplanes require seats protect occupants for hard landing impact up to 35 ft/sec.
Good Lord, coming down at 1,800/fpm and rated to 2,100/fpm?
I would NOT want to be in those conditions.
If landing is about "kissing" the ground, you just about raped it.
Thanks , the interior cabin pic is frightening. Maybe as the A/C had many seats available it may have been an empty row . Bad enough crashing without that coming in on you.
OLYMPIC AIR - ΟΛΥΜΠΙΑΚΗ "Η ΕΛΛΑΔΑ ΨΗΛΑ" "GREECE FLYING HIGH"
Singapore_Air From United Kingdom, joined Nov 2000, 13711 posts, RR: 21 Reply 7, posted (5 years 3 months 3 weeks 2 days 6 hours ago) and read 24136 times:
FoxBravo From United States of America, joined Nov 2003, 2806 posts, RR: 5 Reply 8, posted (5 years 3 months 3 weeks 2 days 6 hours ago) and read 24096 times:
Quoting OA260 (Reply 6): Thanks , the interior cabin pic is frightening. Maybe as the A/C had many seats available it may have been an empty row . Bad enough crashing without that coming in on you.
Unfortunately it wasn't empty! From the article:
"There was only one serious injury, a compound fracture to the leg."
and
"The passenger with the broken leg was sitting next to the point where the right main landing gear punctured the fuselage and pushed into the cabin (pictured below)."
Clickhappy From United States of America, joined Sep 2001, 9444 posts, RR: 72 Reply 9, posted (5 years 3 months 3 weeks 2 days 6 hours ago) and read 24056 times:
AIRLINERS.NET CREW PHOTO SCREENER
The quick access recorder (QAR) saved data and shut down approximately 45 seconds prior to impact. The QAR saves data in batches. It is believed the QAR was working properly and was in the process of saving data when impact occurred, accounting for the “lost” 45 seconds of data.
Does anyone know at what interval the QAR saves data?
LH498 From Germany, joined May 2007, 215 posts, RR: 0 Reply 10, posted (5 years 3 months 3 weeks 2 days 6 hours ago) and read 23982 times:
Quoting OA260 (Reply 6): Thanks , the interior cabin pic is frightening. Maybe as the A/C had many seats available it may have been an empty row . Bad enough crashing without that coming in on you.
Unfortunately no such luck
Quote:
"The passenger with the broken leg was sitting next to the point where the right main landing gear punctured the fuselage and pushed into the cabin (pictured below)."
Stitch From United States of America, joined Jul 2005, 26713 posts, RR: 83 Reply 11, posted (5 years 3 months 3 weeks 2 days 6 hours ago) and read 23922 times:
At least the investigators have narrowed down the possible causes by eliminating a number of things, so hopefully this will result in a quicker discovery of what caused the incident.
Personally, I hope for fuel contamination (water or particulate) since it would mean the rest of BA's fleet is fine.
Tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80 Reply 12, posted (5 years 3 months 3 weeks 2 days 6 hours ago) and read 23923 times:
Quoting Khobar (Reply 1): QAR data is incomplete - it's missing 45 seconds, THE 45 seconds prior to impact (so much for that then)
Not really...the DFDR (Digital Flight Data Recorder) and the QAR are separate critters. The QAR is easier to download so it's the first thing they go for, but the DFDR would also have data and it doesn't save in batches, it's continuous.
Litz From United States of America, joined Dec 2003, 1745 posts, RR: 0 Reply 13, posted (5 years 3 months 3 weeks 2 days 6 hours ago) and read 23896 times:
Any possibility someone who's a member on the PilotsOfAmerica forum could snag the 7 attached pictures?
Their site apparently requires a login to view them ...
Khobar From United States of America, joined Mar 2006, 2379 posts, RR: 4 Reply 14, posted (5 years 3 months 3 weeks 2 days 5 hours ago) and read 23452 times:
Quoting Tdscanuck (Reply 12): Not really...the DFDR (Digital Flight Data Recorder) and the QAR are separate critters. The QAR is easier to download so it's the first thing they go for, but the DFDR would also have data and it doesn't save in batches, it's continuous.
I'm aware of that. Just that we discussed the QAR previously - it sounded like a really good tool, but apparently not so much in this particular case.
Rbgso From United States of America, joined Jun 2006, 575 posts, RR: 0 Reply 15, posted (5 years 3 months 3 weeks 2 days 5 hours ago) and read 23337 times:
Unrelated question....I'm thinking the ship is a writeoff. Would it be economical to repair, if it were even possible?
Stitch From United States of America, joined Jul 2005, 26713 posts, RR: 83 Reply 16, posted (5 years 3 months 3 weeks 2 days 4 hours ago) and read 23185 times:
Quoting Rbgso (Reply 15): Unrelated question....I'm thinking the ship is a writeoff. Would it be economical to repair, if it were even possible?
Pretty sure that one will join RG's on the parts circuit.
BoeingPride800 From United States of America, joined Jun 2004, 429 posts, RR: 2 Reply 17, posted (5 years 3 months 3 weeks 2 days 4 hours ago) and read 22636 times:
I wonder what the row where just outside of it the left main gear ripped through the wing, as it appeared in pictures.
TUIflyer From United Kingdom, joined Jan 2008, 205 posts, RR: 0 Reply 18, posted (5 years 3 months 3 weeks 2 days 3 hours ago) and read 22122 times:
'A detailed report into the crash of a British Airways Boeing 777 at Heathrow has revealed that ice may have been the primary cause.
The report, which was leaked onto an industry forum has stated that ice in the fuel limited fuel flow to the engine. The aircraft was operated in humid and cold conditions , which were perfect for ice formation.
Other findings included the cause of the one serious passenger injury caused by the crash; a broken leg. It is thought that a tyre seperated from the aircraft upon impact and hit the fuselage, this ruptured and pierced the cabin wall on row 30. The impact caused a compound fracture to the passengers right leg.
More details are due to be published at the end of the month, by the Air Accidents Investigation Branch of the UK.'
The impact on Row 30 caused a compound leg fracture, an interesting report.
Halls120 From , joined Dec 1969, posts, RR: Reply 20, posted (5 years 3 months 3 weeks 2 days 1 hour ago) and read 19545 times:
Quoting NYC777 (Thread starter): • Ice in the fuel somehow limiting the fuel flow to the engines. A maintenance message indicating excessive water in the center tank was set during taxi on the two previous flight legs, although it cleared itself both times. The airplane was being operated in a high humidity, cold environment, conducive to ice formation.
• Small-sized contamination building up in the engine fuel systems somehow limited the fuel flow to engine. All the fuel samples have tested for contamination of larger particles (sizes outside the fuel specification). Testing has been started looking for small particles (greater than 5 microns).
this simply cannot be. How many self appointed experts in threads 1 through 8 of the BA crash proclaimed that it COULDN'T have been a fuel problem?????
My, my, my. If these leaked reports are indeed accurate, as Desi Arnaz would say, "someone has got some explainin' to do."
Stitch From United States of America, joined Jul 2005, 26713 posts, RR: 83 Reply 22, posted (5 years 3 months 3 weeks 2 days ago) and read 19221 times:
Quoting Stitch (Reply 11): Personally, I hope for fuel contamination (water or particulate) since it would mean the rest of BA's fleet is fine.
Quoting Flipdewaf (Reply 19): Not just BA's fleet but perhaps all T7s which woulds be much more serious.
Well if it was an EEC software issue, it could be a case of BA not doing it properly since they just added it, but the software has been in service with other carriers for upwards of nine months and would have been tested for months before that.
Hence, I think fuel contamination is more likely since no other BA plane has had the problem and I imagine they too have received the EEC update and seem to be working fine.
Khobar From United States of America, joined Mar 2006, 2379 posts, RR: 4 Reply 23, posted (5 years 3 months 3 weeks 2 days ago) and read 19106 times:
Quoting Halls120 (Reply 20): this simply cannot be. How many self appointed experts in threads 1 through 8 of the BA crash proclaimed that it COULDN'T have been a fuel problem?????
I think they were referring to the plane running out of fuel. The engines were both running at time of impact and the report states that the aircraft had adequate fuel remaining. So those who said the plane did not run out of fuel were correct.
I don't know what other messages you are referring to, but the original report from the crew supposedly said they lost electrical power, and many folks provided reasons why this might have been the root cause rather than a fuel problem. We now know there was no electrical problem.
There were also a number of responses promoting "waxing" as a possibility, and they gave their reasons why.
Maybe there were others that I missed.
As for your response, did you read the report? NYC777 quoted only two of the possibilities being explored. Other possibilities include EEC problem and P30 problem, neither of which are fuel. IOW, although the indications are that the engines were not getting sufficient fuel, it might have nothing to do with the fuel.
Halls120 From , joined Dec 1969, posts, RR: Reply 24, posted (5 years 3 months 3 weeks 2 days ago) and read 18998 times:
Quoting Khobar (Reply 23): As for your response, did you read the report? NYC777 quoted only two of the possibilities being explored.
I did indeed read the report, which is why I said "if" the leaked report was accurate.
Once we have a final report, I'll be more than happy to document all the posts that were "sure" that it wasn't a fuel problem.
25 MI5Flyer: If it was ice in the fuel or some sort of contamination - is this something that could have been avoided? Do they sump the fuel on a large jet or was
26 SNAFlyboy: It's my understanding that it's not necessarily the JET-A freezing, but the water contained in the fuel itself. This is what Prist is used for, albeit
27 BladeLWS: Jet A won't ice like that, but water in the fuel will. And yes there was a warning about water in the center tanks but the warning went away by itsel
28 BladeLWS: The 777 like all modern airliners has fuel tanks heaters. I think it's run from the hot engine lube oil IIRC, but I could be wrong. Also Jet A should
29 Pygmalion: the 777 does not have "fuel tank" heaters... it does have hydraulic pump cooling circuits that use the fuel tanks to cool the oil from the hydraulic p
30 SNAFlyboy: Many thanks for the clarifications... ~SNAFlyboy
31 Mike89406: I don't know much about the 777 but I have to wonder could something have been wrong with the Engine Anti-Ice?
32 TristarSteve: I completely agree with you, but these warnings are well hidden from view. I expect they have been found by downloading the AIMS and MAT memory after
34 Max777geek: Probably the same ones wondering why the fuel problem didn't show up before in the flight ? All the engine feeding discussion makes me wonder : aren'
35 Bobbidooley: Engine Anti-Ice System uses engine bleed air to heat the engine cowl inlets. This has nothing to do with the fuel that reaches the engines.
36 MD80fanatic: Who buys the ice story? How big of an ice chunk can block >15 gallons per minute flow? The plumbing on those engines is 4 inches or more....and any re
37 Baw716: I am not buying ice as the rationale for the failure of fuel to get to the engines. Usually, fuel flows first from the center tank until empty, then t
38 AF1624: Ouch indeed.... That must be terrible. But the "wall" seems rather far from where the legs would be, so the impact must have been REALLY hard. Intere
39 Wirelock: absolutley correct.. the fuel in the centre tanks would have been used by the time they got to LHR.
40 AF1624: Yes but, the center tank would be empty during the approach as it's the first to be emptied during the flight, so ice can't have been the cause as th
41 Wirelock: the fuel cross feed valve should be automatic. if the cross feed valve was faulty this would have been a non dispatch in china for the aircraft IAW M
42 TristarSteve: There are two cross feed fuel valves and they are NOT automatic. Requires crew action to cross feed fuel to the other engine.
43 Dragon6172: I am interested in the findings with the crossfeed valves. Especially the part where it says only one valve was found open. Can someone with knowledg
44 David L: They're not. According to the allegedly leaked information, it's just one of several possibilities under investigation. They are not making up a stor
45 BA777ER236: Sorry, where do you get these figures from? The a/c is tested at normal rate of descent with no flare to touchdown. Normal rate of descent at a groun
46 Glideslope: Why? It's a Boeing. Did not surprise me at all.
47 Wirelock: Ok to be honest am not familiar with the 777 put the valves are monitored?? if there is a fault then the pilots would know about it on the flight dec
48 777WT: Yes it must show the current position of the valve, if a valve was commanded to open and it did not follow up to open command, it will trigger a faul
49 Africawings: Does anyone remember back in 2001 or so when Continental started flying non stop over the North Pole to Asia with a 777ER? They reported problems in t
50 Halls120: So - if the crew opened the crossflow valves just before impact, did they do so because they thought they had a fuel problem?
51 Africawings: Continental Airlines Capatin Quote "For long distance flights, everything is carefully computerized," Capt. Brooks said. Because fuel can freeze durin
52 Analog: I have to say the photos of row 30 don't look as bad as what I had expected looking at photos of the left gear/wing. I guess that's a good thing. Warn
53 Tdscanuck: Anyone who said it couldn't have been a fuel problem was just smoking stuff. Never say never. There were some problems posulated by people with limit
54 BA777ER236: I really doubt it. If there was 'adequate' fuel (& I believe there was a 'normal' amount of fuel) and there had been no 'FUEL TEMP' advisory then I d
55 BA777ER236: Just seen the post by TDSCanuck, must have crossed - very good post and I have repeated some of your stuff, sorry. Cheers
56 Spacecadet: Exactly - it seems like some people either aren't reading far enough or they're not comprehending what they're reading. These are the possibilities b
57 ATCGOD: For polar flights most airlines take a sample of the fuel and then calculate out what temperature exactly it will freeze and later send the informati
58 KELPkid: I do. In early jet engines, there were screen filters before the fuel was injected into the combustors. If the fuel was cold-soaked and happened to h
59 Khobar: The function of this device may be partly to "make it easier to keep the engine fuel metering smooth", but it is also prevents "waxing". There are so
60 Dragon6172: Thanks for the info. I can probably guarantee that the 777 system is the more complicated system. I flew on H-46 helos, really a very simple system t
61 Sprout5199: A little OT, but this sort of sounds like what happened to the USS Thresher(SSN-593). The things you don't think of are the ones that will kill you.
62 Tdscanuck: Unfortunately, having both engines suck from the same thank through the same pipe is exactly what happens when you open the crossfeed valve. I took a
63 Dakota123: Once the center tank is down to unusable quantity, how is the system precluded from drawing down further? In other words, how is air precluded from e
64 Halls120: Well, we must have some heavy smokers on Anet! I wasn't blaming anyone, BTW. Just curious as to why they would have done it, and you've provided an e
65 Analog: If the filters are what get clogged, they'd have to both get clogged either very quickly or at very closely matching rates for this theory to hold wa
66 Khobar: If the filters get clogged, a by-pass valve opens.
67 KELPkid: And I'd imagine the flight crew gets sun burnt by the resulting EICAS warnings (Just guessing here, I don't know the 777 well enough to know...)
68 Dragon6172: And if the filters get clogged and the bypass valve gets stuck?
69 Tdscanuck: All of the boost pumps are connected to the common fuel feed line by check valves. Since the boost pumps functionally can't pump air (they're low-pre
70 Khobar: You have a fuel clog resulting in a flame-out/engine shutdown (as was the case I posted), or maybe not - I guess it depends on what's clogging the sy
71 474218: The door surrounds (frames) have to be strong. When the opening is made in the fuselage for a door, the door surround has to take the place of all th
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