WARNING!!!
 

Some of you are not very bright are you? This thread is about the missing AF A330.

We allow some educated theorising about what may have happened and we also allow explanations of associated systems (hardware and natural) that could explain some of the possibilities. However, those of you who haven't figured out yet why your technical discussions on Faraday cages or the differences between X band and C band radar keep disappearing are prime examples of why this thread has to be moderated all the time.

Take your technical debates to the Tech Log forum. You are wasting all your time and effort trying to wave your willies at each other on this thread.

Also, all those outraged types who think that somehow airline pilots who post on anonymous forums have to somehow live up to their imaginations had better get a real life soon. Airline pilots come from all backgrounds and have their own opinions on everything. Whether we agree or not is of no concern to the idiots who come on here and blather on about how badly behaved pilots are when they have no idea whether they are indeed pilots or just spotty faced anoraks whose closest association to a/c flight controls are the keys on their computer and some flight sim software.

I'll reopen this thread but any of those time wasters who haven't figured out yet that this is not a private chat room for them to try and convince the other about how knowledgeable they are about one system or another, had better realise that there are specific forums for their debates and this thread is not it.

If you don't want what you write on here deleted then think before you post it. Is it directly relevant to the topic? Are you guessing or using ill sourced info such as what you have heard from the media? are just trying to let us all know how grieved you are about the tragedy? Think carefully and you won't waste yours and our time!

BOAC Flapsnegative - you appear to have been in the area at the time? Was there any chat on 123 about the ride there? Do you know if the (reported) ?TAM? a/c report of 'fire sighted' was reported on 121, HF or 123?

We were at UN866 at FL370 around the time, the AF was at the UN873, one airway to the east. Neither on 123 or 121 there was talk about the missing airbus, not surprising since the A330 went officially missing only several hours later. We didn't hear a TAM report on floating fire either, but there was some low level ELT-like noise on the 121, but it was so faint and brief that it came over the squelch treshold for just one or two seconds, so it is quite improbable to have originated from an aircraft below.

Also there was a post on blue jets lightning, we didn't notice any discharges from above or below, but the moon was actually quite clear when above the clouds (helpful for reference in manual flight without prim or stby instruments, but not within CB) so that could have prevented sighting of a blue jet.
The top of the clouds we experienced at that time I would estimate at FL400, but in the ITCZ it's nowhere the same, it could easily be much higher nearby.

That is indeed the greatest concern. I'm not sure why anyone is even talking about a lightning strike being a cause of this horrible accident in the face of growing evidence via ACARS messages and transposed weather analysis that the aircraft was being subjected to a sustained measure of severe to extreme turbulence just prior to being lost.

The aircraft doesn't have a lightning strike detector and the pilot didn't report a strike! The whole "lightning" theory was put forth as an off-the-cuff extrapolation from a "short" message when it hadn't come to light there was also a susequent 4-minute stream of other messages showing the autopilot disconnect, reversion to abnormal law, other electical failures, and cabin press problems.

IF the aircraft encountered severe-to-extreme turbulence at high altitude (that accounted for the autopilot off and abnormal law), heavy with fuel, and quickly ended up in a jet upset (which would explain the AP/abnormal law) where the only path brought you into more developing weather, the chances for engine flame-out (cabine press problems) would also be high during the whole event and the aerodynamic forces even more extreme including torsional forces no aircraft is designed to withstand.

I think many are on a "Can't see the forest for the trees" snipe hunt there because their interest or hobby lies with electrics. If anyone steps away from the keyboard, however, and pushes their computer from the desk to the floor and proceeds to kicks it around, you'll get those same kind of messages if it could report it. Those electrical faults did not happen outside the much larger problem of that entire aircraft being subjected to severe outside conditions.

I believe (yes, speculate) this tragic event was a result of a severe/extreme turbulence enounter at altitude still heavy with fuel, and subsequent jet upset..ACARS electrical report of failures a result of equipment being hammered ....with a subsequent loss of aerodynamic and engine control.

The "Forest" here is the aerodynamic/aircraft control issue due to severe-to-extreme turbulence because the aircraft was operating at high altitude. It's just not about the Airbus being able to handle the stress of such turbulence directly if it's flying right-side up below is Turbulent Air penetration speed with plenty of margin between stall and overspeed, the hull probably can. But if the aircraft was heavy for FL 350, slowing to a turbulent air penetration speed also brings any aircraft at high altitude closer to the AOA where control can be lost if it's hit with other, sudden outside forces and the flight controls can't respond quickly enough.

The training for recovering from a loss of an aerodynamic loss-of-control event at high altitude in jet, transport aircraft is minimal to none and given the pilots may have to attempt it during continuous, CB-produced turbulence is perhaps impossible. That's why flying into forecast areas of even moderate turbulence at heavy at high altitude where buffet margins are close is to be avoided, and anything severe escaped with haste, the problem being initiating a higher-than-half bank (such as when you're hand-flying which it seem these AF pilots may have had to) turn after you're in it possibly making the difference between staying inside your buffet boundary and going outside it.

Anyway, the electric faults would more likely be a result of something going aerodynamically amiss with this flight related to the weather, not a cause for it going amiss. I don't buy the "lightning strike made bad things happen" scenario a bit. Lightning is a small worry yes, but it's the LAST thing that's worrisome about operating in close/too-close proximity to severe thunderstorms. Some have latched onto it because it happened to be included in the "possibility" first statement given by a PR man at AF, and are experiencing a Primacy of Learning tunnel-vision, IMO.

Aerodynamics, not Electrics, would seem to be the right tree to be barking up. Given moder aircraft design, explaining the loss of an aircraft due to electrical fault-as-beginning-the-failure-cascade scenarios is exceedingly difficult at best.

Explaining electrical faults (as well as other system faults and the pilots inability to communicate) due to severe buffeting and aerodynamic loss of control and engines seems far more likely, and not a "first time in history, one in a million chance" occurance. These things have happened too many times, and it's why aviators learned long before anyone here began their careers avoiding those weather conditions takes priority over all else, and loss of control at high altitude is a can of stress and engine control worms nobody want to ever open.

This aircraft was 3 hrs into a flight fueled for an 11hr trip, and at FL350, over 200 pax. Can any of you experienced Airbus 330-200 guys tell us what the likely weight and the low-end buffet boundaries for for that weight would be? And what max turb air penetration speed is? What was the ISA deviation at FL350 in that area that night?

Jurassicjockey wrote:
Once the cockpit depends on something, it has to be fairly bullet-proof and the kinds of drop outs that you can get from satellite based internet let alone servers operated by third-parties. Having once worked on avionics, I can say that getting anything new built into a commercial cockpit is a long and painful process.

SAR Effort
 

To Heli Sticktime et al
Re-capping the official info released so far regarding the ongoing SAR effort on the Recife ACC and SOLANT ACC area covered by CINDACTA III, what we have is as follows:

a) At 0230LT/01062009 a C-130H staging through SBRF and an Embraer P-95 maritime patrol acft based at SBSV were enlisted to perform the initial SAR effort;

b) On 1908LT/01062009, the following additional SAR assets were called-up:
- 01 x Sikorsky UH-60L Black Hawk to SBNT;
- 01 x SC-95C (SAR version of the EMB-110P2) to SBNT;
- 01 x CASA C-295M SAR-configured acft to SBNT;
- 01 x Eurocopter AS332M SAR-configured helicopter to SBNT;
- 01 x C-130E to SBNT with SAR rescue teams;
- 01 x C-130H to SBFN, backtracking along AF447s flight path from GCLP to SBFN;
- 01 x Brazilian Navy Frigate (with SAR-configured Sea Lynx helicopter);
- 01 x Brazilian Navy Patrol ship;
- 01 x Brazilian Navy Corvette

c) At 1930LT/01062009 an Embraer R-99B SIGINT/ELINT acft was enlisted to aid in the AF447 SAR effort;

d) At 0029LT/02062009 The Brazilian AF stated that the crew of TAM flight inbound to Brazil spotted "luminous points" on the ocean's surface within the boundaries of the Dakar ACC

e) At 0100LT/02062009 Brazilian AF R-99B 6751's synthetic aperture radar plotted metallic and non-metallic debris floating on the ocean surface roughly 650km NW of SBFN;

f) At 0649LT/02062009 Brazilian AF C-130H 2466 and C-130H 2474 made visual contact with debris plotted by R-99B 6751's SAR. The debris fields were approximately 59km apart and roughly south of AF447's filght path. The debris fields contained an aircraft passenger seat, an orange float ou buoy, a drum or cylinder, several small unidentified white-colored items and oil/jet fuel slicks.

Cheers

There's a lot of speculation to what the messages that were transmitted by the aircraft back to France. A lot of information could be obtained from them as they would be in order of occurance. The ground based software to analyse this is called AIRMAN for Airbus aircraft.

It will give all the cockpit effects(ECAM warnings etc), class 1 and class 2 maintenance messages. Basically if you've ever seen the PFR after a flight thats exactly whats on the AIRMAN system, but in near real time.

What would be the effect on a modern airliner such as the A330 if it experienced a high speed stall at high altitude? I seem to recall a 737-800 coming close to experiencing such an event which required flying at slightly reduced altitudes by the airline for a period afterwards whilst it was investigated. Unfounded speculation of course but if the A330 was operating at 41,000 ft with significant load and optimum cruising speed and then encountered unexpected severe turbulence could this cause such a stall and could the damage to the aeroplane be severe enough to cause a break up?

Given the considerable advances in ground-based weather radar over the past decade, one wonders whether this technology has been somewhat neglected by a/c manufacturers/operators? Also, there must be other technologies out there which could significantly enhance the detection of CBs (LIDAR, optical systems etc). Lightning can be detected at considerable ranges using very straightforward RF detection equipment.

Cockpit access to satellite radar
 

My question is whether pilots have access in the cockpit to IR radar images of the type that are available from NOAA or other govt/commercial providers. From the analysis of the weather at the time of the incident (available within this thread) it seems that the AF pilots could easily have diverted around the cells that they entered, but maybe their weather avoidance radar malfunctioned or did not show them the "big picture". Seems like having the most recent satellite radar onboard would be very helpful for choosing the path of least weather resistance.

SAR Effort
 

Hi CDG1
The latest info indicated that two merchant vessels were already in the general area where the debris fields were spotted, with a third MV on its way to the site. I understand that two MVs are French, while the third is a Dutch ship.

According to Brazilian Navy spokesperson, the three MVs are tasked solely with retrieving survivors or bodies. Should any of the vessels sight aircraft parts or components, they are instructed to identify and plot their position - but not retrieve. A Brazilian Navy vesselis enroute to the site and is expected to arrive on the morning of June 3rd.

The Brazilian Navy spokesperson relayed information regarding local weather conditions and sea state (1.5 to 2m waves, 30ºC water temp and 15 kt wind).Barring other factors, that would seem to indicate that retrieving debris will be somewhat easier than expected.

Cheers

Has anyone heard if any ships have reached the area where debris were spotted?

There was talk of two Dutch vessels and a French freighter rerouting themselves as they were said not to be too far away.

Dutch ship was said to be "Jo Cedar" and French freighter was said to be "Douce France". Are there any more news on this?

I don't know if I'd say it's taken "so long" to pin point the crash site. The debris has been located. There are other factors such as current and whether the aircraft may have broken up in air or upon hitting the surface to consider.

All things considered, I'd say the remnants of the air craft have been located rather quickly.
:D to the men and women involved in the recovery.

Speeds For Amf
 

AMF,

According to the QRH and based on a weight around 210t:

(speeds are approximate)

Green Dot (minimum clean speed): 245 kts

Turbulence penetration speed: 260 kts

Vls w/ 0.3g buffett margin: 235 kts

Speeds are all indicated so no ISA deviation necessary.

SAR effort
 

Hi YHZ Chick
I think that it'd be premature to state that AF447's wreckage has been found inasmuch as what was sighted earlier today was from a C-130H flying, at best, 500ft to 1000ft ASL.

The idea is to retrieve whatever components are found in the two debris fields, find mfg serial numbers and determine whether these match or not what was installed in AF447's airframe. And that will only be possible after such items are collected - which will not happen before tomorrow. If you factor in the time to correctly identify whatever is found and see whether the serial numbers match, and chances are that a positive or negative ID will only be available some time between Thursday or Friday.

Unless, of course, they find a chunk of sheet metal with the register "F-GZCP" painted on it...

Cheers

What Happened......Dont ask me???
 

First of all I really am impressed with the effort of some (only some) of the "professional" guys here who actually went to the length of plotting the exact (or very near) location of that a/c, and provided all sorts of data for that flight .:D

However, with my experience of nearly 10 years of working on A330s (and lots more) I really am surprised with the amount of half baked knowledge some guys have about the actual a/c and its systems. I am not slagging anyone but it sounds ridiculous to try and sound like aviation experts whilst quoting the media news here.:ugh:

I will better clarify some things about A330 systems ( from a Techies perspective) in the Tech Log....in the meantime I will let guys here make assumptions and shoot in the dark as to what happened.....mind you we are all speculating and doing the same...but blaming Lightening strikes, or Composites or some kind of 'Short Circuit' tells us who knows what about how it works...carry on guys....you are doing fine :ok:.....as mentioned earlier....wasting yours and others time!!!

Not all journos are idiots
 

Storm threat to modern aircraft

BBC NEWS | Americas | Storm threat to modern aircraft

Thank you Snaproll.

So only 15kts IAS between Min Clean speed and Max Turb Air Penetration speed for that weight at appx 210tn, and 25kts between the same and Low Speed Buffet margin.

As we know exceeding the Max Turb speed during severe/extreme will wreak havoc on components at the least, and any aircraft is in danger of structural damage under those conditions. And we all know what can happen if the low-speed buffet margin is suddenly exceeded.

My ISA question is related to the performance/ability of the engines to accelerate an aircraft of that weight out of a turbulence-induced low-speed condition at that altitude.

Another Airbus 330-200 question related to the ACARS messages that the A/P had disengaged and reverted to Abnormal Law. I assume the Airbus has an automatic low-bank (or 1/2 bank) function or it's equivalent when the aircraft is at high altitude under even normal, smooth conditions that protects the aircraft from a wing-loading stall condition where the buffet margin is small.

My question is, on this type of Airbus does this bank protection still exist at high altitude during non-AP operation in Abornmal Law?

Benbecula

You wrote:

"For pilots who dismiss lightning strikes as almost harmless, well, you'd be right. Up to 95% of the time. It is unlikely to happen, but it can and has bought down aircraft, Pan Am 214 is an example."

Pan Am 214 was brought down by a lightning strike in 1963 only 4 years after the Boeing 707 was introduced. Boeing redesigned the fuel vent outlets so it could not happen again. It is not really appropriate to use that accident which happened 46 years ago to substantiate your argument of how dangerous lightning strikes can be.

tailchase post at 1922
 

Sad logical conjecture
59 km seperation of debris fields possibly suggests aerial breakup into 2 components. , the second component remaining airborne for longer and flying further.but a dense weight fell earlier to the water.at a shorter distance*(engine?)
Or, a lighter draggier component fluttered down at a later time but travelled a shorter distance (part of tail,or blown out airframe part?)
Even if the first part came off and fell vertically the second part travelled at 32 miles or more (controlled descent?)

Short answer.... No

Heavy aircraft can experience a stall or "Mach Buffet" (stalling of the wing due to supersonic flow) at much lower altitudes than 41,000.

AF447 could have experienced some form low speed stall, Mach Buffet stall, or "Jet Upset" due to turbulence, but a proper recovery would not put the aircraft in an over-stress situation.

It is generally a poor recovery technique that causes the loss of an aircraft in these situations.

SOURCE : BBC
Not sure if that will go down well with the mods here at the moment - since any reference to structural overloading of components seems to warrant deletion. No matter what the source or how qualified one might be.Specifically, in my case - the entire transcript of public hearings held by the NTSB concerning AA587.

The various protections available in each flight law may be explained on this site:

SmartCockpit - Airbus 330

Thats a good source of generic Airbus information. It's not specific to each company but most conform to the airbus procedures.

The short answer is that there are still protections available in Alternate Law, not Abnormal Law, although I guess thats gramtically correct, but that's just semantics.

I'm out for tonight, catch up again from Oz.

re: tailchase post at 1922
 

"59 km seperation of debris fields possibly suggests aerial breakup into 2 components."

If it were on solid ground, maybe... but you have to take ocean currents into the consideration here. On top of that, there's no confirmation yet that the two debris fields are related

I am thinking Pulkovo 612, the other recent instance when a plane crashed during cruise in a severe thunderstorm. Except no sophisticated electronics or composites were involved. That case was thoroughly investigated, and it was concluded that flight at near ceiling + severe turbulence = stall +double flameout = loss of control.

Optimum use of Weather Radar
 

http://www.airbus.com/store/mm_repos...V_WX-SEQ07.pdf

Of particular interest from this note is (emphasis mine):

"It is important to note that reflectivity of particles is not directly proportional to the hazard that may be encountered in a cell. Air can be very humid, when close to the sea for instance. In this case, thermal convection will produce clouds that are full of water. These clouds will have a high reflectivity, but will not necessarily be a high threat. On the other hand, there are equatorial overland regions where converging winds produce large scale uplifts of dry air. The resulting weather cells have much less reflectivity than mid-latitude convective cells, making them much harder to detect. However turbulence in or above such clouds may have a higher intensity than indicated by the image on the weather radar display."

And CMC ( central maintenance system ) is powered by AC1 normal and AC ESS on gnd ......

Jo Cedar
 

One of the commercial MV diverted to search looks like it is in a search pattern now. Link to position plot.

JO CEDAR tracking map

While debris reports give locations to the southeast of route, various maps of ocean currents in that area shows the flow to be toward northwest. That would rule out currents.

Brazilian secretary of defence Jobim just stated that the FAB has spotted a 5 km wide (long?) area of debries and that there would be no more doubts that they are of AF447...

DAC
 

Watching to a FAB spokesman on TV today I heard the word barrel/drum.
Makes me wonder about the cargo manifest and if there was any DAC, Dangerous Air Cargo.

Reuters, Tuesday June 2 2009

Not likely to be the case, currents are likely to be uniform over several 10's of miles so if debris went in over an area of a few miles they would stay that way for some time. Even if they happened to fall at a boundary between 2 oceanic currents the drift would only be a Knt or two, insignificant over a few hours. A few exceptions of course but I don’t think there would be any in this area.

Final Four Minutes of Reports
 

We can deduce:

The Satcom was powered at least until after the last ACARS message, so other systems to keep the plane controllable should have been powered also.

There was not so much flight upset that it took the Satcom antenna out of line of sight of the geostationary satellite, which would have been almost directly overhead. What kind of antenna did it have?

The Satcom antenna was receiving valid steering signals from an IRU to keep it pointed, since it was surely a steered antenna.

GB

AF447 SAR effort
 

Hi Guardian 11
I'm not a pilot. But I have a question to the FAB (Brazilian Air Force); The last tower contact with cindacta 3 was 22:33 right? At 2:20 FAB started to search for the lost aircraft. My question is; why did it take 4 hours for them to realize that?

Perhaps to better understand the problem, it would be best to review the timeline leading up to the mishap...

At 2233LT, AF447 performed a VHF contact with CINDACTA III (SOLANT ACC), reporting INTOL, indicating that it expected to report TASIL at 2320LT;

At 2248LT, AF447 exited CINDACTA III radar coverage. At the time the flight was cruising at FL350 and 453kts - as per the flight plan;

At 2314LT, AF447 issued a number of ACARS messages to AF maintenance center;

At 2320LT, AF447 failed to report its passage by TASIL and entry into Dakar ACC.

Failure to report waypoint passage at the expected time does not entail the immediate launching of a SAR operation. Unless, of course, a distress call is made or an ELT transmission is detected - and neither occurred. Under those circumstances, there is a standard waiting period before placing SAR resources on alert status. At the moment I cannot recall the duration of that waiting period, but I very faintly recall a 90min period - but I might be in error.

Hence, should memory be serving me correctly, the Brazilian SAR system would only be placed on alert footing at around at 00:50LT. Once placed on alert status - and in the absence of solid information as to where the event took place - you can add an hour for mission planning and preparation.

As for resorting to Mirage 2000s, bear in mind that these are based at SBAN - which entails a 1.880 km flight to SBNT - easily a 2:30hr flight. They would have to land at SBNT, refuel and then take-off to fly some 1.200 km to the general area where the mishap might have taken place. Although I do not have the Mirage 2000C performance charts at hand, I think it would be safe to say that a pair of Mirage 2000Cs would be unable to execute a meaningful search pattern, in the dark of night, for more than 10min before reaching "bingo fuel"...

Cheers

For what it's worth (not much):

Today, a TP pilot that was flying a paralell route (in his words about 80nm west from the AF's route) at basically the same time and in a similar acft (not said in the interview, but it would be a TP's A330 or A340) was interviewed in a portuguese TV channel (TVI).
For those who understand portuguese, the vid of the interview can be watched here.

Basically he said that:
- He doesn't believe a plane can be brought down only by turbulence. Although not impossible but highly unprobable.
- He doesn't believe in a single factor for the accident
- He stated that aircrafts are prepared for lightening strikes.
- He found turbulence on his flight path but nothing "unusual" for that particular route. He did had to re-route to avoid, but nothing unusual (10/15nm).
- He didn't hear any distress call from the AF's crew
- He acknowledge that sometimes they experience difficulties with radio (HF) transmissions and "use" other aircrafts to relay the information
- He DID hear some requests from the ATC to other acft in the 'area' to try to reach AF447 on different frequencies, including another TP flight that departed from Natal

He spent a good part of the interview "evading" the (usual at that TV station) sensacionalism-inducing questions, and stick to the (IMHO correct) posture of "noone knows nothing for sure at the moment and I'm not going to speculate, but it was a strange and fast happening".

./J
(an idiotic anorak)

If the debris is in the north equatorial counter current it could drift eastward at up to 3 knots which is like 70nm in 24hours:

from: The North Equatorial Counter Current

hey wiley...check your definitions of turbulence
 

saw you on CNN and you spoke of mild turbulence

that isn't in my AIM!
light

moderate

severe

extreme

Well as someone has seen fit to delete my link to and quote from the BBC lets try again. An official statment says that the wreckage 400 miles off the Brazilian coast is from the aircraft.

France is sending a reasearch ship with two mini subs.

Does anyone know the exact level of turbulence reported by the flight some 14 minutes prior to the last transmission of data?

I've heard the Air France head use the term "heavy" turbulence. Would this correspond to ''severe'' or extreme. Was the turbulence report made by the crew?

Applying proper recovery technique might not be possible if the aircraft was descending in conditions as severe as what caused the jet upset in the first place, say, down through the CBs they were flying above and around. On top of that, there's the issue of engine flameout due to aerodynamic blanketing, hail, fuel pump unporting, or component failure of auto-relight features, etc.

The fact is, most pilots train for unusual attitude recovery where the recovery is accomplished in benign conditions with all flight controls working normally, a full panel, not to mention the engines running and outside visual reference. Many places don't even give "jet upset" training...i.e. loss of aerodynamic control at high altitude.

And a real-world jet upset, let alone sever or extreme turbulence involving all the forces, cannot be rendered or trained well in a simulator because the test pilots during certification don't even put the aircraft through those paces.

Ole, of course ocean currents aren't constant. Go here, click the map section for recent charted flow depictions. You can even play a java-loop. No eastward flow is depicted in the debris area
http://i.cdn.turner.com/cnn/2009/ima...azil.plane.jpg