High Altitude Operations Supplement #1 to the Airplane Upset Recovery Training Aid Assembled by the Industry Airplane Upset Recovery Training Aid Team, October 5, 2008
A MOST interesting piece of airline training litterature....
Put together by a team lead by 2 test pilots specialists at BOEING and AIRBUS.
Great stuff ! and note the date of this revision 2....
If the aircraft had been spinning at impact I do not think the fin would have separated as it did; there would have been torsional evidence.
Where are the tps/structural engineers to back up my opinion?
I think you'll need a metallurgist and a structural engineer to determine how that VS separated. For what it's worth, I don't buy BEA's forward shear theory at impact.
It will be interesting to know the locations of the power plants, when they are eventually found. Relatively close together would imply she stalled in, widely separated would imply a spin. Not forgetting the fact that she still had another 3 miles to travel post impact.
WillRogers (I think) was right, will still need to know the cause of the upset; the consequences are all too obvious.
If it stalled (for whatever reason) and then suffered double flameout due disturbed airflow to the fans then;
lost HYD due no engines/ RAT (which would not work if the aircraft was stalled/ Green HYD had no electrix for the G pump) / much the same for APU then;
had no flight controls (due no HYD);
could not be recovered by the crew in any circumstances.
Pitots + CB have got to be the ingredients and a stall to the sea the outcome.
I've been following this thread since shortly after the accident happened. As a frequent flyer (100K+ miles a year on UAL alone) I have an amateur interest in aviation. My professional interest is in satellite observing systems, both on the development side and regarding technical and regulatory matters involved in getting the data from them out to the users. I am posting here in an attempt to find out whether there is anything that the satellite community in particular can do to help prevent a repeat of what happened here. My apologies in advance if this post is out of line with the purpose of the board.
Reading this thread has been very informative for me, so thanks to all of you who are sharing your knowledge with us. I understand that we still do not know exactly what transpired, and I don't have the qualifications to add to the speculation or hypothesizing about it. Without going into details about that or about who might be at fault, I will for now assume that weather played a primary role. My assumption is very simple: For some reason AF447 ended up in the middle of an active thunderstorm in circumstances that exceeded the combined capabilities of the aircraft and its pilots.
For areas beyond coverage of ground-based radar networks, the best source of information about convective weather is generally the geostationary satellite system. AF447 went down somewhere near 2 deg N, 30 deg W, in an area for which satellite coverage is provided by both the US (GOES-E operated by NOAA/NESDIS) and Europe (EUMETSAT's Meteosat-9). Being of a more recent generation, the Meteosat-9 imager is slightly more capable (12 channels, 15 minute repeat cycle) than the GOES imager (5 channels, 30 minute repeat). From cross-referencing the cloud-top temperatures measured from satellite with the ACARS messages, we now seem to believe that AF447 was in an area of (surrounded by?) Cb's topping out at 50,000+ ft when things started to go wrong. Since these satellite data are processed and disseminated in real time, in principle there ought to have been a way for the pilots themselves to know that, possibly and hopefully before actually finding themselves there. Assuming now that this was not the case, there are two possible reasons: 1. The data aren't acquired and processed fast enough to keep up with the convective development, or 2. The data are not made available to the flight crew.
Concerning the former, it is true that neither of these two satellite systems have image repeat rates meeting the formal requirements adopted by the World Meteorological Organization, namely 10 minute (or better). This can obviously be a problem for very rapidly developing systems and that may or may not have been a factor here. The next generation imager to be flown by the US on GOES-R in the 2015 time frame will - depending on scan mode - be able to provide full-disc imagery every 5 minutes. However, unless these data in some form actually make it all the way to the flight deck they may not be of much help in the kind of situation we are discussing here.
So my questions to those of you who fly transoceanic routes in areas of convective weather are the following:
1. Do you have in-flight access to geostationary satellite images (or to products derived from them, such as instability indices or cloud top temperatures)?
2. If the answer to 1. is yes: Do you consider this useful for instance when crossing the ITCZ? If not, what would you like to see changed in the data you have access to?
3. If the answer to 1. is no: Why don't you ? Is it a communications/aircraft systems issue? ... a data policy issue? ... due to fear of information overload?
If we accept the fact that the aircraft has not altered its course and stayed rather precisely on the UN873, and knowing what was the weather with CBs activity in this area (see various post s, sites or the report etc...) can we imagine one second that the radar might have become inoperative and, in this case, what would have been the various alerts received by the crew and what would have been the ACARS report(s). Sorry but i really can't understand what she was doing here. Also do any drivers here have already noticed one day that their wx radar was freezing or not answering etc... Just trying to understand...
Last edited by Squawk_ident : 3rd July 2009 at 13:23.
why go into a storm? only if they didn't know the storm was there would they go in.
wondering RADAR imperfections?
And speaking of upsets...wondering if you all remember the chinese 747, lost an engine in cruise...crew didn't notice...autopilot held altitude until airspeed was too slow...bam
they recovered and made a safe landing at KSFO...I personally saw what hapened to the horizontal stabilizer. I can imagine that the airbus 330 might not be quite as robust.
And speaking of upsets...wondering if you all remember the chinese 747, lost an engine in cruise...crew didn't notice...autopilot held altitude until airspeed was too slow...bam
Never mind the facts .......
About 1016 Pacific standard time, February 19, 1985, China Airlines Flight 006, a Boeing 747 SP-09, enroute to Los Angeles, California from Taipei, Taiwan, suffered an inflight upset. The flight from Taipei to about 300 nmi northwest of San Francisco was uneventful and the airplane was flying at about 41,000 feet mean sea level when the No. 4 engine lost power. During the attempt to recover and restore normal power on the No.4 engine, the airplane rolled to the right, nosed over, and entered an uncontrollable descent. The captain was unable to restore the airplane to stable flight until it had descended to 9,500 feet. After the captain stabilized the airplane, he elected to divert to San Francisco International Airport, where a safe landing was made. Although the airplane suffered major structural damage during the upset, descent, and subsequent recovery, only 2 persons among the 274 passengers and crew on board were injured seriously.
1. Do you have in-flight access to geostationary satellite images (or to products derived from them, such as instability indices or cloud top temperatures)?
2. If the answer to 1. is yes: Do you consider this useful for instance when crossing the ITCZ? If not, what would you like to see changed in the data you have access to?
3. If the answer to 1. is no: Why don't you ? Is it a communications/aircraft systems issue? ... a data policy issue? ... due to fear of information overload?
1. Guess most airlines do not yet have it. Those products are available already via satcom data to several bizjets and can be displayed via various means in the cockpit..as most modern airliners can be equipped the same way.. the technology is here and the providers of said products are here
2. It IS useful on a strategic level for weather zones as the ITCZ. Strategic meaning in this case, as being able to see developments hundreds of miles away, which is not possible with radar and plan accordingly
on a "tactical" level, i.e. weather avoidance 50 to 100 miles ahead radar still is more useful, but again, if the strategic avoidance is better with the sat products, your final tactical avoidance may be easier too and may yield better results at times..
3. There should not be any big data communication problems and looking at a sat picture should not pose any data overload..
so, yes, everybody should have it..
should make life out there a tiny bit easier
the technology is out there, no problems, and costs should not be an issue..
Marsk -- somewhere in this thread, someone with some experience points out that such real-time satellite data is not available on most flight decks.
Everyone reading the english version of the BEA report should check out the French version for the graphics (which presumably make up the bulk of the 10 megabyte difference in file size): there are some impressive reconstructions of the storms based on the 0207 and 0215 satellite shots, with the 0210 ACARS position report superimposed.
If anything comes out of this accident, I'm betting it's systematic training on the use of weather radar and making near-real-time satellite weather info available in-cockpit.
Another thing -- the report puts the CG at around 37-38% aft at the time of the accident. Any sort of spin I assume would kill the engines. Am I mistaken in assuming that, even if the RAT works there (which it's not designed to do), you'll be in direct law, where elevator control is by trim only?
also, JD-EE: Yes. Pedantry is appreciated! And to everyone else: professionals in the field call him William of Ockham, or just "Ockham", hence "Ockham's Razor." The name is based on his birthplace in Surrey. I understand that some of you might have wasted some time stooging about there. We have that in common.
Another thing -- the report puts the CG at around 37-38% aft at the time of the accident. Any sort of spin I assume would kill the engines. Am I mistaken in assuming that, even if the RAT works there (which it's not designed to do), you'll be in direct law, where elevator control is by trim only?
I believe that direct law still controls the elevator. It just has a very simple (hence "direct") control relationship between sidestick and elevator, whereas the various higher-order control schemes are a bit more sophisticated. What you're thinking of is the backup system if all the PRIMs and SEcs go u/s. (apologies for not using the precise terminology, I'm going to go find it now if I can)
OK, found it again, full explanation here of the control scheme
Quote:
DIRECT LAW Direct law is the lowest level of computer flight control and occurs with certain multiple failures.
* Pilot control inputs are transmitted unmodified to the control surfaces, providing a direct relationship between sidestick and control surface.
* Control sensitivity depends on airspeed and NO autotrimming is available.
* An amber message USE MAN PITCH TRIM appears on the PFD.
* If the flight controls degrade to Alternate Law, Direct Law automatically becomes active when the landing gear is extended if no autopilots are engaged. If an autopilot is engaged, the airplane will remain in Alternate Law until the autopilot is disconnected.
* There are no protections provided in Direct Law, however overspeed and stall aural warnings are provided.
* The PFD airspeed scale remains the same as in Alternate Law.
o ADIRU2 (1FP2) (2 h 11) ATA: 341234 Source: IR2 Identifiers: *EFCS1, IR1, IR3 Class 1, HARD This message has not been fully explained at this stage of the investigation. It was generated by IR 2, but it is possible that the correlation window had been opened by EFCS 1 via a class 2 message.
Maybe the related message is
Quote:
o FCPC2(2CE2)/WRG:ADIRU1 BUS ADR1-2 TO FCPC2 (2 h 10) ATA: 279334 Source: *EFCS1 Identifiers: *EFCS2 Class 2, HARD This message indicates that FCPC 2 no longer considers as valid the information that is delivered to it by ADR 1 (via bus 2). The ATA code beginning with 27 indicates that the fault was not detected by any other FCPC during the three seconds that followed (otherwise this message would have been classified ATA 34). This message has not been fully explained at this stage of the investigation.
Marsk -- somewhere in this thread, someone with some experience points out that such real-time satellite data is not available on most flight decks.
Thanks. The fact that someone had already pointed out the absence of real-time satellite data had escaped me, but given much of the discussion of the limitations of the onboard radar I am not surprised.
falconer1 wrote:
Quote:
Quote:
1. Do you have in-flight access to geostationary satellite images (or to products derived from them, such as instability indices or cloud top temperatures)?
2. If the answer to 1. is yes: Do you consider this useful for instance when crossing the ITCZ? If not, what would you like to see changed in the data you have access to?
3. If the answer to 1. is no: Why don't you ? Is it a communications/aircraft systems issue? ... a data policy issue? ... due to fear of information overload?
1. Guess most airlines do not yet have it. Those products are available already via satcom data to several bizjets and can be displayed via various means in the cockpit..as most modern airliners can be equipped the same way.. the technology is here and the providers of said products are here
2. It IS useful on a strategic level for weather zones as the ITCZ. Strategic meaning in this case, as being able to see developments hundreds of miles away, which is not possible with radar and plan accordingly
on a "tactical" level, i.e. weather avoidance 50 to 100 miles ahead radar still is more useful, but again, if the strategic avoidance is better with the sat products, your final tactical avoidance may be easier too and may yield better results at times..
3. There should not be any big data communication problems and looking at a sat picture should not pose any data overload..
so, yes, everybody should have it..
should make life out there a tiny bit easier
the technology is out there, no problems, and costs should not be an issue..
Thanks. Given that a strategic deviation from the planned track should be less onerous in terms of time and fuel than a tactical one, there should be some value in having the satellite data available also for that reason. I hadn't thought of that.
My point was that the satellites (passive vis/infrared measurement) see something totally different from what the radar (active microwave measurement) depicts. The radar basically shows precip, the satellites show cloud top temperatures and in some cases pre-convective instability. Next generation geostationary satellites are planned to carry lightning mappers showing cloud-to-cloud lightning, thus providing yet a third source of information about convective weather. For the US this is considered a done deal, for Europe this could conceivably still fall apart due to funding issues.
The technology is clearly there so if cost is not an issue, what is preventing airline flight crews from having access to these data?
They flew into a thunderstorm. The A330-203 was at max cruise altitude and at faster than normal mach (because of the high/heavy choice). Mach .82 and encountering moderate turbulence and most likely warming temps when they got a vertical gust of XX knots. Who knows, who cares. Iced pitots? Who knows, who cares, same result. The ADIRU's are programmed to 'fail' with a loss or gain of 60 knots, because that is thought to be impossible. They were entering an area of increasingly worse/impossible conditions for their planned performance prior to encountering/stumbling into a buildup.
The plane stalled. The engine/s probably flamed out/overtemped/burped because the inlet air also vectored off of normal due to the vertical gust. If only one was producing thrust, the plane may have even flatly spun, but it did so in a stalled condition. 208 metric tonnes falling from FL350 after a stall will look the same as a rock. They remained stalled all the way down. Vertical fin and pieces of a horizontal stab were found floating. How much tail remained on the way down? Who knows, not enough, obviously. None of this surprises me. The ACARS messages are nice to have, but fact is, they would be expected in this scenario.
I have flown this EXACT route several hundred times in 37 years, and no prudent aviator is going to ignore the weather in this region.
Sorry to be blunt, but anyone who has ever penetrated an active thunderstorm (for whatever reason) will do whatever it takes to never do it again.
Provided they survive their first encounter.
The Old/Bold rule.
Another small tidbit. Within an hour of the impact 7 other flights went within 100 miles of AF447 that night, and every night since, and not a single one of them has made CNN.
Sorry I think Occams' Razor applies here.
I'm in agreement. The theory that something must have failed/iced over/ blah blah is being focused on by those who are ignorant of what an inadvertent CB or bona fide severe turbulence encounter can mean in terms of indicated air data and very real aerodynamics if you're too high and too heavy.
Everything about this event points to a loss of aerydynamics/jet upset, most probably due to convective activity, and not a coincidental instrument or mechanical failure. ACARS messages have only served as a tail to wag the dog for 80% of this thread, IMO. Like you say, those ACARS messages would be expected in that scenario.
In the absence of information another possibility? It is easier to assess the things that data suggest, especially when the alternative would be to impugn or call into question the skill of the crew, and that without data.
It is why I wanted there to be no Horizon on the panel, with it, one assumes there was a way out. I have been borne by winds that treated me and the a/c as if I was a feather, and landed white as a sheet. I resist the thought the crew may have entered a bad one, I know the feeling. Hope this isn't histrionic.
The technology is clearly there so if cost is not an issue, what is preventing airline flight crews from having access to these data?
fresh sat charts in the cockpit ...
well, honestly have no idea??
you would not even need any big expensive "certified" installations, just take your lap top in the cockpit, most modern airliners have high speed data internet access via satcom, here you go...
beats me why it's obviously not yet the norm..??
but I am sure, nobody will leave home without it a couple of years from now..
Linear Mode
