Erroll 80 #126 June 5, 2009 According to Sky, none of the wreckage found so far come from the Air France jet. QuoteBrigadier Ramon Cardoso, director of Brazilian air traffic control, said: "Up to now, no material from the plane has been recovered. We confirm that the pallet found is not part of the debris of the plane. It's a pallet that was in the area, but considered more to be trash. He also said a big oil slick originally thought to come from the plane probably also came from a ship passing through the zone, 600 miles off Brazil's coa(s)t. The fuel slick had originally been used as evidence to suggest the plane did not explode - now a theory under question. Full Skynews article Quote Share this post Link to post Share on other sites
MikeForsythe 0 #127 June 5, 2009 QuoteThat is just one of the maaaaaaaany NTSB reports that I have gone over where no mayday, holy shit, we are fucked, nothing was transmitted before they augered in like Wile E.I guess you did not read my previous posts. I specifically stated commercial aviation and not general where a lack of communication is common. Thanks for proving my point.QuoteSo the plane is coming apart and you have the rest of your life to try to get it stable and you think the first thing of the crews mind would be to TRY to tell someone where the crash scene is gonna be. RIIIIIGHT!Again, you need to read my previous posts as I never said to stop flying the plane to attempt communicaion. Also, you try and make it like only one pilot was flying, do you have anything to support that since there were three pilots?QuoteHow do you know it was up? More speculation. What if the breakup took out the comm's?Yes, it is theory based on fact. There was no telemetry to indicate any com failures. QuoteSure why not!My plane is coming apart and the first thing I'm gonna do is reach for the FMC and start typing a SATCOM message.I guess if you had read the paragraph in whole and in context you would have realized that I was discussing voice communication only and the reason that I listed it last is because of the uplink time.Time and pressure will always show you who a person really is! Quote Share this post Link to post Share on other sites
quade 4 #128 June 5, 2009 Quote Interesting article. Thanks. I especially like "Figure 4". The use of the conceptual block diagram to illustrate the operation of the system while the aircraft is in an unusual attitude was a brilliant touch. I'm not even sure how a person does that.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
Rookie120 0 #129 June 5, 2009 QuoteI guess you did not read my previous posts. I specifically stated commercial aviation and not general That was a commercial flight not GA. Well I should say corporate. But if you want a commercial crash with no MAYDAY here ya go! http://www.ntsb.gov/ntsb/GenPDF.asp?id=DCA02MA001&rpt=fa I can do this all day. It's not uncommon or unusual. It happens.If you find yourself in a fair fight, your tactics suck! Quote Share this post Link to post Share on other sites
MikeForsythe 0 #130 June 5, 2009 QuoteI can do this all day. It's not uncommon or unusual. It happens.It is very uncommon. You might want to read the report. There was only like 15 sec from loss of the vertical stabilizer to impact and only 10.2 sec from stall warning. And I did not say it never happened and even cited an example when it did. I challenge you to find a similar accident where they had that kind of altitude and time and made no communication attempt.Time and pressure will always show you who a person really is! Quote Share this post Link to post Share on other sites
Rookie120 0 #131 June 5, 2009 QuoteI challenge you to find a similar accident where they had that kind of altitude and time and made no communication attempt. I have shown you that it happens now you want more? What are you saying? You say something smells because no com's transmitted. So what are you getting at? I am trying to figure out what you are thinking or trying to say.If you find yourself in a fair fight, your tactics suck! Quote Share this post Link to post Share on other sites
nigel99 561 #132 June 5, 2009 Quote This doesn't look good. http://www.msnbc.msn.com/id/31040692/ Firstly I really feel for the families involved in this, and hope that there is some closure for them. I've been generally following the news on the accident and came across this statement in a BBC news article Quote Meteorologists say that the Air France Flight 447 had entered an unusual storm with 100mph (160km/h) updrafts that sucked water up from the ocean. As the moisture reached the plane's high altitude it quickly froze in -40C temperatures. The updrafts would also have created dangerous turbulence, they say Does anyone know if this "means" anything or is simply commentators stating facts that may or may not be relevant? I read this to imply that the plane may have been damaged by ice (not buildup of ice)?Experienced jumper - someone who has made mistakes more often than I have and lived. Quote Share this post Link to post Share on other sites
SkyDekker 1,465 #133 June 5, 2009 QuoteI read this to imply that the plane may have been damaged by ice (not buildup of ice)? Which is possible. It is also possible that the build up of ice caused faulty speed readings. speeding up in heavy turbulence can cause a plane to have catastrophic failures. My uncle who is a captain for AA wrote me the following: "A storm of that magnitude is a prime candidate for attenuation, a phenomena where a cell is so massive that on board radar can not penetrate it enough to show its true image. The radar image will then show a much thinner storm, with ( a dead giveaway ) no returns behind it. Better radar versions will warn of attenuation with contrasting colors ( blue or yellow ) when a shorter range, 40nm, is selected, in the shape of a cone behind the suspect storm. Selecting a longer range may not display that feature, and what looks like a thin line of weather with clear sailing behind may actually be the worst of conditions." In response to this info here: http://www.weathergraphics.com/tim/af447/ Quote Share this post Link to post Share on other sites
quade 4 #134 June 5, 2009 QuoteQuoteMeteorologists say that the Air France Flight 447 had entered an unusual storm with 100mph (160km/h) updrafts that sucked water up from the ocean. As the moisture reached the plane's high altitude it quickly froze in -40C temperatures. The updrafts would also have created dangerous turbulence, they say Does anyone know if this "means" anything or is simply commentators stating facts that may or may not be relevant? I read this to imply that the plane may have been damaged by ice (not buildup of ice)? The big thing here is the intensity of the storm. Big storms have turbulence and hail that can do a lot of damage. Aircraft entering areas of severe turbulence need to stay at or below a certain speed that changes depending on the weight of the plane. This speed is known as Va. The idea is that at or below Va, no matter how large the turbulence, the aircraft will momentarily stall and unload the flight surfaces before they can break. At least, that's always been the theory, real life has shown conditions or pilots can fail otherwise numerous times with various aircraft. Additionally, ice buildup is an issue if it were to build up or otherwise damage air data sensors. In a fly by wire airplane, having air data sensors fail can cause the airplane to divert from the desired flight path. Do that in an area of severe turbulence and if the aircraft commands an increase in thrust to correct for a perceived loss in airspeed which ends up taking it over Va . . .quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
MikeForsythe 0 #135 June 5, 2009 Paul, I can see where the pitot tubes could freeze up but don't they also use GPS?Time and pressure will always show you who a person really is! Quote Share this post Link to post Share on other sites
JohnMitchell 16 #136 June 5, 2009 QuotePaul, I can see where the pitot tubes could freeze up but don't they also use GPS? GPS will tell you where you are and which way you are going, but it won't tell you which way you are pointing, in other words pitch, yaw and roll, all very important to flight. Quote Share this post Link to post Share on other sites
Brains 2 #137 June 5, 2009 Stop it! Neither of you were there, and no matter what you can't change the outcome! Never look down on someone, unless they are going down on you. Quote Share this post Link to post Share on other sites
Rookie120 0 #138 June 5, 2009 QuoteStop it! Neither of you were there, and no matter what you can't change the outcome! No shit! I am just wondering why he keeps harping on the no distress call.If you find yourself in a fair fight, your tactics suck! Quote Share this post Link to post Share on other sites
Brains 2 #139 June 5, 2009 Quote Quote Stop it! Neither of you were there, and no matter what you can't change the outcome! No shit! I am just wondering why he keeps harping on the no distress call. Because you keep responding!!!!!! Never look down on someone, unless they are going down on you. Quote Share this post Link to post Share on other sites
quade 4 #140 June 5, 2009 QuotePaul, I can see where the pitot tubes could freeze up but don't they also use GPS? GPS tells you your speed in 3D space relative to the ground. That's meaningless when it comes to telling you your airspeed. Also, understand that pitot tubes have heat in them to help prevent them from getting iced to begin with, but that doesn't mean that a baseball sized chunk of hail couldn't take them out. As I said much earlier, there are lots of "normal" ways that an airplane can fail.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
SkydiveJack 1 #141 June 5, 2009 QuoteQuotePaul, I can see where the pitot tubes could freeze up but don't they also use GPS? GPS tells you your speed in 3D space relative to the ground. That's meaningless when it comes to telling you your airspeed. Also, understand that pitot tubes have heat in them to help prevent them from getting iced to begin with, but that doesn't mean that a baseball sized chunk of hail couldn't take them out. As I said much earlier, there are lots of "normal" ways that an airplane can fail. GPS derived speed is your speed over the ground. It is not your airspeed (speed through the air). Airspeed is sensed by the pitot tubes and transmitted to the airspeed indicators and the autopilot. Normally only one pitot tube at a time supplies the airspeed information to the autopilot. The autopilot is linked to the auto-throttles (on aircraft like the A330 that are equiped with this system). An indication of slowing speed will cause the auto-throttles to advance in order to maintain the airspeed that the flight crew previously selected. If the airspeed sensed by the pitot tubes is incorrect (in this case, too low) the aircraft can accelerate through it's maximum operating speed without setting off the overspeed horn. I'm not saying this is what caused the aircraft to crash. I'm just clairifying how this particular system works in reference to some of the previous comments. Quote Share this post Link to post Share on other sites
wolfriverjoe 1,523 #142 June 5, 2009 Airspeed sensing is dependent on the static ports in addition to the pitot tube (ram air pressure compared to static air pressure). If the static ports were blocked by ice, then the altitude and airspeed would get very screwey. There was a crash (South America?) caused by the static ports being covered (neglected to remove covering tape after cleaning and polishing). THunderstorms are very bad news. And this one sounds worse than average."There are NO situations which do not call for a French Maid outfit." Lucky McSwervy "~ya don't GET old by being weak & stupid!" - Airtwardo Quote Share this post Link to post Share on other sites
lawrocket 3 #143 June 5, 2009 QuoteThe idea is that at or below Va, no matter how large the turbulence, the aircraft will momentarily stall and unload the flight surfaces before they can break. So here's another idea I had a couple of days ago before this news started coming out. Again - I am not exactly up on this. If the craft was cruising at 450 knots (I'm pulling that number outta thin air) airspeed, with a Va of 500, I would think that with a storm such as the one described to be encountered that airspeed can change to 525 knots within a few seconds. If there is some rotation (which considering the updrafts seems to be a strong probability) that what may have been a 15 knot wind coming from the front-starboard may become a 75 knot wind from front-port in seconds. You then hit strong turbulence suddenly as you are now thrust to 525 knots - 25 knots above Va. This could occur whether or not the pitot tube was iced. If it was, well, another thing adding up to doom it. My wife is hotter than your wife. Quote Share this post Link to post Share on other sites
quade 4 #144 June 5, 2009 Typically large aircraft have several "cruise" speeds according to the task at hand. These will all usually be well below Vne, the speed at which you should never exceed even in smooth air. Va, turbulent penetration airspeed, is usually a bit below even "economy cruise", which is more or less the speed this aircraft on this type of flight would be using. All of the above said, it's not the momentary shifts in airspeed that matter but the vertical and side gusts that are of major concern at altitude. Think of Va as the speed at which you'd want to go over a speed bump so that your suspension doesn't get ripped out. That is by no means a perfect model, but close enough for jazz here. Additionally, there have been occasions where Va hasn't been calculated and the aircraft engineered as perfectly as one would want.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
MikeForsythe 0 #145 June 5, 2009 ***Thanks Paul and John that explains a lot. There are now reports that another flight saw a large flash and then a vertical drop in the area of the flight. What would be the likelihood of a cloud to cloud lightning strike through the cockpit or the ebay right under them? That could explain everything that we know to date.Time and pressure will always show you who a person really is! Quote Share this post Link to post Share on other sites
quade 4 #146 June 5, 2009 Quote***Thanks Paul and John that explains a lot. There are now reports that another flight saw a large flash and then a vertical drop in the area of the flight. What would be the likelihood of a cloud to cloud lightning strike through the cockpit or the ebay right under them? That could explain everything that we know to date. Generally speaking, lightning travels around the outside of the skin of the aircraft. This isn't a perfect video, but it will show you the basics; http://www.youtube.com/watch?v=ve6XGKZxYxA That's not to say that -something- couldn't have happened with the electrical system, but . . . generally speaking I doubt if that alone would be enough to take down the airplane. I can't find the real video I want to show you of some military test flight through lightning. There's a really great one I remember seeing where they intentionally flew through lightning storms to gather data about strikes. The plane is hit over and over with nothing really happening to it except some burnt paint.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
Rookie120 0 #147 June 5, 2009 QuoteI can't find the real video I want to show you of some military test flight through lightning. I think I have seen the video yuor talking about but I cannot find it. Here is a video that shows what one looks like. http://www.youtube.com/watch?v=pDTDt2NZLmMIf you find yourself in a fair fight, your tactics suck! Quote Share this post Link to post Share on other sites
billvon 3,064 #148 June 5, 2009 >I can see where the pitot tubes could freeze up but don't they also use GPS? Yes, and in fact the ACARS messages had GPS information encoded in them. The bigger problem comes about when the system loses air data. (The ADIRU fault would indicate that there were serious problems with attitude, airspeed and altitude sensors.) When that happens, the system can no longer maintain control of the airplane, and thus the system reverts to a simpler control law, one where a pilot's input is connected more directly to the flight surfaces. (or worse yet, the computer believes the data and starts diving the aircraft or something to "compensate.") In this simpler control mode the pilot is flying the aircraft more directly, but loses some of the 'protections' that come with the normal fly-by-wire control laws. So this is a possible scenario: An upset occurs that causes the flight control computers to switch to an alternate control law. This could be turbulence that causes the aircraft to exceed bank or pitch limits, or it could be icing on a static port that causes air-data errors. The pilot then takes control of the aircraft, but due to strong turbulence, over-controls the aircraft and exceeds the design limits. (Since the fly-by-wire system is not operating normally, the computer will no longer prevent him from doing this.) Part of the airframe fails and the remaining computers trip off-line because the inputs they are seeing are, according to them, impossible. The aircraft becomes uncontrollable and eventually starts breaking up. The last message sent is cabin depressurization as the structural integrity of the cabin is compromised. I use this scenario because that's what happened to the A300 in the JFK accident in 2001. The pilot encountered turbulence, over-controlled in yaw and snapped off the vertical stabilizer. That caused loss of control and other structural failures before the aircraft hit the ground. In that case they were low and so had only 15 seconds or so to try to deal with it. In this case they were considerably higher and thus may have been in the air for a longer time, giving the ACARS system time to send more messages. Quote Share this post Link to post Share on other sites
Rookie120 0 #149 June 5, 2009 Quote(or worse yet, the computer believes the data and starts diving the aircraft or something to "compensate.") In simple terms the A/P got vertigo.If you find yourself in a fair fight, your tactics suck! Quote Share this post Link to post Share on other sites
ryoder 1,590 #150 June 6, 2009 Can anyone tell if this is just a summary, or if this is the entire ACARS message stream? http://img32.imageshack.us/img32/7547/acarsaf447d.png"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones. Quote Share this post Link to post Share on other sites
