There never was an issue of a bomb. The Airbus was transmitting fault data when the aircraft went down. It was in a huge severe thunderstorm off Africa when it crashed. But there is a larger issue of Airbus safety.

1) The Airbus design has long been questioned. When a jet is cruising at altitude it must stay within a very narrow range of airspeeds. This range is called the Q-corner or coffin corner. If you fly even a small amount below the coffin corner, the aircraft loses life and plunges downward, most probably in a flat spin. It the jet is too fast, it literally can take the wings right off it. In Airbuses the coffin corner is as little 30 knots (33 mph.) Competitive Boeing jets have more than double the coffin corner.

2) Airspeed readings are obtained from a series of pitot tubes located around the aircraft. You cannot determine airspeed with GPS satellites or LORAN or RFD. Pitot tubes are mechanical and very susceptible to icing or other conditions which either give incorrect or no airspeed readings. Most Airbus's have at least 5 pitot tubes.

3) The Airbus autopilot has also been responsible for several accidents and is extremely counter-intuitive. When a malfunction is detected the autopilot disconnects and the pilot takes over. The Airbus autopilot is unique in that it only partially disconnects, often without warning, and the pilot is suddenly in control and has to figure out which controls disconnected and which are still overriding him and why the autopilot disconnected in the first place. This can take precious seconds in an emergency. Boeing autopilots give more warning, give the pilot control over everything that he exerts control over, and notifies the pilot of why the disconnect happened.

4) The Airbus fly-by-wire systems are also heavily criticized for lack of redundancy.

The most likely scenario is that at altitude, and in an extremely heavy thunderstorm, the pitot tube were damaged by hail or lightening strikes or iced up. (We know from transmitted error data that inconsistent airspeed readings were being recorded.) Suddenly control is given back to the pilots without any valid way of knowing airspeed and solidly in the coffin corner. This is a recipe for the airliner to exceed the coffin corner and literally fall apart in midair.

Chris - informative post. Thank you. Out of curiosity, what is your background?

Agreed, very informative. Never flying on an Airbus.

The pilots had room for error of about 2mph, once it lost auto-pilot, they had to get the right airspeed to keep from stalling, and with the commotion of ALL the sirens going off in the cockpit, and not being able to tell their altitude, a recipe for disaster. They should've NEVER flown into the storm to begin with, but their radar doesnt' penetrate outward enough to be able to get the full glimpse of the size of the storm. If this happened in daylight, they would've seen to NOT fly into it. Very sad way to go.

Chris,

While it is obvious you know a thing or two about aviation, your anti-Airbus bias is incredible. Every airliner has had incidents and accidents (hear about metal fatigue on the 737's?) There is no "design flaw" in Airbus aircraft. There are operational procedures for the pitot malfunctions you mentioned. Chris, please use your knowledge to educate people rather than scare people. The latter makes you no better than a journalist

You should see that video of the Airbus flown entirely by computer. Not sure who was unhappier. The Airbus folks or the trees.

http://www.youtube.com/watch?v=Y1FKAIrb0fQ

@ The (Airbus) Company - If Chris' points are valid, then they're valid regardless of whether he is Anti-Airbus or not. It's also quite possible, that they are a big reason why he is anti-Airbus. People are allowed to have opinions, and his is that Airbus is unsafe for all the reasons he's listed. If you disagree, argue with his points, not his opinion.

Having watched a NOVA special about this accident, much of what Chris says was backed up in that special. The point about the Q-corner was made in the special, but also said that if airspeed is lost, pilots are trained to handle the situation by setting the plane to a certain flap setting and power setting where the q-corner is much larger and the result of those settings is stable flight. They put pilots in a simulator, in a thunderstorm and knocked out the pitot tubes. These pilots didn't know what would happen and handled the situation properly. The NOVA special hypothisized that the pitot tubes failed, the auto-pilot diconnected (known from error broadcasts) and the pilots made an error recovering from this situation. Ultimately pilot error.

The other point in the NOAVA special was that simulators can only tilt a certain amount, and modern commercial pilots have so much automation, they are not experienced really doing stick and rudder flying in extreme situation. That if the plane did stall, it should even have been recoverable with good flying skills, but these pilots had never been in a large jet in a stall with the plane at extreme angles. Pilots don't do stall training like you do in a cessna, they do it in a simulator. So these pilots were put into a situation that was outside of their experiences and they made a mistake or two. They didn't react quickly enough with the throttles and flaps they needed to do in a matter of seconds and they couldn't pull out of a stall they had no real experience handling, even though they were experienced pilots.

p-cola, regarding the radar, the Nova special showed NASA satallite images from that night. There was a small rain cloud between the plane and the large storm. Radar would not have penetrated the small rain cloud. The situation is probably that the pilots thought they would flying into a small rain cloud, came out the back of the cloud and had a massive severe thunderstorm in front of them that it was too late to avoid.

Another point in the NOVA special I just remembered that supports Chris dislike of airbus systems. When an airbus auto-pilot is engaged, it adjusts the throttle but does not move the throttle levers. So the throttle levers don't represent the actual throttle position. Boeings do move the throttle levers. So when the autopilot disengages the throttle is left where it was, which is probably not what the throttle levers are saying. So instead of glancing at the throttles to see what the throttles are at, you have an unintuitive process to try to recover from an auto-pilot disconnect.

Chris sounds like he knows what he is talking about, but he does not. Coffin Corner is not a design feature of an airplane. It is a control and conditions issue and every airplane with poweful enough engines can get into its Coffin Corner.

Saying that the Coffin Corner marigin for a plane is X knots makes as much sense as saying that a maximum radius for a safe turn for a car is X degrees, period (completely omitting variables like speed and center of mass of the load).

You can get any jet aircraft capable of climbing too high for its own good into a coffin corner. You might say that operating procedures of Boeing require pilots to stay withing 60 knots marigin of the Coffin Corner, but that is bull, all you need is a pilot who wants to safe on fuel and a nice storm with a sudden pressure drop to get you in trouble.

The pitot tube freezing can contribute to the problem in the sense that you can accelerate to the point where you cross your critical Mach number, but you do nto have to be in a coffin corner for that to happen.

Of course if you are high enough to stall and buffet at the same time your chance of recovery is a solid 0 no matter what you fly.

Chris,

If the airbus was transmitting fault data then it would have been transmitting the airspeed and altitude correct? Should be a logical scenario formed by now if the airbus was in fact transmitting fault data.

Also, most sophisticated planes have dual airspeed monitors. Primary and secondary. The aircraft I worked on had a backup. When the primary and the secondary disagree you get a visual indication, voice indication and audible beeps in the headset.

I find it hard to believe the secondary was jacked up also. Those two systems are independent of each other. The primary deals with digital data and the backup deals with analog old school indicators.

Once you get the "somethings wrong" indication there is usually a lever you switch over to backup.

Seems odd nothing alerted the pilots about their airspeed and altitude.

Chris

Your comment with regards to the coffin corner is applicable with ALL airliners and planes that fly at higher altitudes (Boeing's, Airbus, Illushin, Tupolev, Gulfstream, Bombardier, Embraer etc...). The specific range is a function of various factors, including temperature, air pressure (which will vary at altitude) and other weather factors, in addition to some specific airplane design issues. By stating this as an Airbus only issue is misleading at best, fear mongering at worst.

As for Pitot related issues, Boeing planes have had issues that have led to accidents as well. At these altitudes, it really doesn't matter if the plane is fly by wire or not, if you can't rely on the information being received from your instruments, then you are going to have issues.

As for the auto-pilot items, auto-pilot isn't what it used to be. It really depends on the mode that your auto-pilot is set to. Boeings do the same thing. The A310 accident that you are probably referring to in Russia where only part of the auto-pilot disengaged is NOT a fly by wire airliner, so the example does not apply (that is assuming that you were referring to that incident where this scenario occurred).

As for Redundancy, IIRC correctly, the Airbus Fly-By-Wire system has as much redundancy as a war plane does. It has two COMPLETELY different systems which handle two different aspects of the flight regime with multiple backups for each system. Most of what the fly-by-wire does however is just relay the pilot commands to the flight control surfaces. The ONLY limits that it applies is when the plane starts to exceed certain flight control limits. The 777 does almost the same thing, just differently (though the 777 does let you exceed those limits, the plane makes it extremely difficult to do so). If the instrumentation was incorrect, then the fly by wire would have been irrelevant, the pilots flying at altitude at night over water would have become disoriented, and if they couldn't rely on their instruments, they would have fared no better. (you might want to look up the Air Peru accident in the Boeing 757, a non fly by wire plane in a similar instrument related problem)

One thing that needs to be reinforced though is that we don't know what caused this accident. We can only suspect the cause. The instrument malfunctions that were reported COULD have been faulty data transmitted to the satellite and it may have not had anything to do with the instruments themselves. Only finding the black boxes will answer those questions. Any other discussion is pure hypothetical.

Jonathan

Sam

How do you know that nothing alerted the pilots about problems. The CVR's have never been recovered.

lmao he doesnt but i think he might be a boeing employee . not that i care, in either way . but lol if you over/under speed 33 mph your gonna die . that seema a bit tight . so anyways just saying .

oh gents there is a difference between "fault " and "faulty " data . just so all the aerospace engineers here can ponder something different .

beachbums,

You can get yourself as close as 10 or 5 knots to coffin corner on any plane. It is just a matter of the conditions and/or a pilot decision. However being so close you can literally have a regular stall on one wing and flow separation on the other during a turn, which is a very bad situation to be in.

It is called a "coffin corner" for a reason. Otherwise it would be called someting nice like a "rose corner" or "unicorn and pony corner".... LOL...

Jonathan,

Good point. I don't know. What I do know is that no pilot chooses to fly through a thunderstorm unless they have no choice. I do know this aircraft has an independent pitot-static system. I read this aircraft has a 7400 to 13,000 km range. I do know that Rio to Paris is 9100 km. I do know it fell out of the sky just shy of Paris.

Now, if a plane has a 7400 km minimum why is it attempting to fly to 9100 without a stop in between?

A large number of warnings (as reported) suggest massive internal issues or loss of power. If they lost power then all sorts of warning would go off. The pitot angle did not do this. That plane lost power inflight. Maybe it ran out of fuel.

That's the only way I would fly through a thunderstorm over the Atlantic. That's if I had no choice but to fly through it. And the only reason to make that choice is because of fuel or emergency.

Chris-749391 Before you write a comment please do your research so you know what you are talking about. I am a 10 year aviation maintenance veteran, both in military and civilian avaition. Im an avionics technician and licensed airframe and powerplant mechanic that currently works on airbus A-320, A-300-600, A310-200 AND 300 SERIES AND A-330-200 and 300 series aircraft, and yes Ive worked Boeing 737, 757, 767, and 747..
The A330 aircraft has ONLY 3 pitot tubes. One is the captains, one is the First Officers andf the other is for the standby air speed indicator. All 3 of these pitot tubes have anti-icing elements built in to them and is controlled via the TAT or total ait temp sensor which will turn on anti icing equipment in the event of icing conditions. Now you also have your static ports on eithe3r side of the airplane that feed pressure measurements to your digital airdata computers to tell pilots their altitude and also corrects the airspeed for diff altitudes which gives them their mach limits as airspeed changes due to altitude. Those to have anti icing capabilities. As far as the autopilot, it will fully disengage in the event of one of the 3 systems faulting or will automatically switch to the redundant systems.. now in the event of a serious issue the flight warning computer will let the crew know of any problems in the aircraft and actually tells them what steps to take.. the pilots can manually disengage the autopilot with the click of a switch or physically over-ride the system which will also disengage the autopilot. Also your 30 knot limitation is incorrect as well,
You are correct that there are airspeed limitations, but they apply to mostly to when the aircraft is in a take-offr or landing configuration due to flap-slats, landing gear, and or spoilers being deployed, but when the plane is in a clean config it has a much higher airspeed window, but this depends on the aircrafts altitude. Your theory of a pitot probe malfunction is faulted as all 3 tubes operate independent systems so all 3 systems would have to fail. A lightning strike would only effect 1-2 probes at the most but would not render them inop. More then likely and this is just an educated guess from an experienced avionics technician who tests these systems to meet RVSM (Reduced Vertical Separation Minimums), ETOPS (Extended Twin engine Operations) and CAT 3 (Automated Inclement Weather Landing Systems), the aircraft ran in to severe wind shearing that causes a loss of lift to the wings that was so severe that the pilots were unable to recover from. The airbus has a very robust lightning protection design so that is probably out as well. The planes autopilot and navigation computers are triple redundant and continuously cross monitor and cross talk to prevent erroneous data being sent to the flight crew. Thank You for your time and this has been your Introduction in to Avionics 101 lol

Gee GD. They had three previous attempts to locate...and the publics want to know "immediately" what happened to anything today causes wild speculation, and of course, terrorism. It just might help to get the facts straight first. I'm just sayin..............

Swarles-

They do put 'locator beacons' on them. They transmit a signal for at least two weeks, but like anything that emits a signal, it must be working properly and something must be close enough to receive that signal.

They do put a locator beacon on the black boxes. But it has been so long that the batteries are long dead.

Regarding the black boxes... I suggest they place a "pop-off" beacon with antenna on them (after relocating the pop-off to a appropriate area). If a water crash, the beacon would (upon nearing or reaching the water surface) immediately send the GPS coordinates of the beacon. If land area (such as the Alps or Ural mountains) would also immediately send the GPS coordinates.

Certainly, some design work would need to be done but this is well understood technology and would eliminate the question, "What is the nearest known location of the crash site?"

It took what, 70 years befor they found the Titanic? If it wasn't for the technology, this plane might be lost forever. 2 years are forever for the families, but now there might be some answers and closure too.

First off, if any kind of bomb had damaged the plane it would be transmitting fault data. Could have also been a second bomb or the first one caused damage that was unrecoverable IF there was a bomb. Just because there have been some Airbus issues I would not rule out terrorism. It should be considered as much as anything else.

One other point for Chris, the plane went down off Brazil and not Africa

ACS: The problem with "pop-off" beacons is wreckage can drift quite a ways in various directions once it sinks, esp if it's sinking 10,000ft, wreckage could easily be spread over hundreds of square miles. If it "pops-off" at the bottom, then there is no way to recieve the GPS signals under that much water and so the beacon could again drift a long ways before reaching the surface and a GPS signal.

A good replacement for a black box locator would be an "absolute-zero" temperature element, it could be detected easily.

I remember a satellite NASA launched a few years ago with an absolute zero mirror on it, some were complaining because that "cooler than space" mirror could be detected from the whole galaxy, and eventually antagonistic aliens.

Swarles

There is a beacon on the Flight Data Recorders. But the batteries in them can only last for so long. The combination of the sea bed terrain and the depth made it extremely difficult to locate them prior to the batteries dying.

Driving to Europe can be a bit tricky, this time of year.

Yeah mark...but I have trouble finding a filling station under the ocean.

"This why I don't fly, its a big time risk. I rather drive"

The above statement is nonsense. See below:

"There were 0.2 fatal accidents per 1 million departures in the United States in 2008, compared to 1.4 per 1 million departures in 1989, for example, and a review of the statistics in intervening years shows an improving trend overall"

"The lifetime odds of dying of heart disease are 1-in-5 (based on 2001 statistics), while those of dying in an auto accident are 1-in-100. The odds of dying in an air travel accident are 1-in-20,000"

John Kimble - Thanks for shedding some logic on the silly fear of flying. It's always so shocking that people think that driving is even remotely safer than flying.

John, you are correct. Statistically you are pretty safe. It's the perception here that is the problem. Most of us don't hear about all the vehicle accidents that are happening all the time but when an airliner crashes it kills a lot of people at once, it becomes the headlines across the country (globe?)

Personally I just don't like to fly. I do like to drive and I do enjoy seeing the country side a bit closer to the ground. So it is certainly a choice we can make, but we should put this in proper perspective and not blurt out unsubstantiated "information".

Even so, I think it's a good thing that they've found the wreckage. I hope that the family members can finally find some closure and comfort.

i think the concern for some people is the loss of control.

The belief is that if they drive, at least they will have control of their life, rather than putting this control in somebody else's hands. Plus driving is a much more familiar and comforting means of transportation.

But they don't have control to lose. You can only lose the illusion of control.

Just this weekend a student of ours was driving his car and got t-boned by a truck. I'm sure he "controlled" that to happen.

Does your car float?

I LOVE flying! I don't like sitting around airports waiting for delays because there's a problem in another airport! So I don't - I drive, if at all possible.

I've spent entirely too much time waiting for flights in Philadelphia. Worst damn airport I've ever been in!

UncleBob,

It's all relative. Sure you dont have full control over everything while driving, but you can still control your speed, driving safely, your route, whether you want to drive into a crazy goddamn storm or not...

And everything in this world is about how we perceive things, whether it's real/actual or not.

pilots on new planes only have to enter data for autopilot and autoloand systems, a drunk can easily do this job

Just because you can control the vehicle you are in doesn't mean you can control the thousands of other vehicles that you will pass on your drive. . .

But can a drunk fly the bird when it all hits the fan, and the systems crash or keep flashing "error", or do you just write off the bird and passengers?

Just because you can control your vehicle and what you do with it does not mean that you have control over the other vehicles that you will pass on your trip. You have no control over drunk drivers or those that fall asleep behind the wheel.... You can "perceive" (seems to be the used most in the posts agree with this post) if that car crossing over the median and into your lane head on is real or not, your choice.

I don't mind flying so much - mostly just the hassle at the airport. So I drive whenever possible, or take the bus or train.

or kennedys brain ?

Jimmy Hoffa is currently living a quiet life in retirement in a suburb of Phoenix. I just spoke with him a couple of weeks ago, and he is doing just fine.

Lets see... he's about 98 years old. And doing just fine? Wonderful.

It's the clean air in the desert, I guess....

Jim: How is Elvis doing?

Last time we chatted, which was about a month ago, Elv said the bursitis was acting-up again and that he was having difficulty doing his pelvic gyrations. I'll tell The King that you were inquiring on the next occasion we speak together, Doug.

You got it! The feds moved him a long time ago along with a lot of other "missing" mobsters people think got wacked.

As Swarles remarked, it is most likely a function of depth and pressure. I read some time back that there aren't all that many organisms at that depth, and that it is cold enough to slow decomposition.

Ya, but the Frenchie's legal system is charging them with a manslaughter. Here is how this is handled in Europe:

http://www.personneltoday.com/articles/2010/02/18/54149/corporate-manslaughter-new-guidelines-for-sentencing.html

Easy to say when your relatives aren't in the bottom of the ocean bloating from water and being eaten by underwater marine life.

Good thought, but how would you come to the number 28 million? Plus, the reason for the crash may be priceless for future knowledge. Plus, let us not forget the poor families that don't have closure. Closure may be more important to a family than any amount of money.

Once dead - dead. The living would like a few million to assuage their grief.

winsettz, the bodies aren't bloating or being eaten by sealife. There is very little to no life at that depth, and the oceans pressure keeps the bodies from bloating. They will however, once they're brought to the surface.

Indeed. All it took to get them off their asses to actually hire a firm capable of finding this wreckage was to be charged with multiple counts of manslaughter.

Air France and/ or Airbus certainly don't want NTSB or anyone else qualified looking into what took this plane down.

Well done by this judge!

rockmebritney - Airlines and aircraft manufacturers have an obligation to determine the cause of a crash and how or if it could have been prevented. If it was equipment malfunction wouldn't you want to know that the cause had been discovered and corrected before you took a flight in the same kind of plane? The idea is not to lose more lives because no one bothered to fix the problem.

Tea: This is the THIRD search of the area, not the first. Air France also used extensive French Navy assets in the initial recovery effort.

That was my point.
A firm CAPABLE found the wreckage.

28 million divided among th families of the passengers and crew....you seriously think (assuming a one time payment was made to one family member) that approximately 120,000 dollars is enough to make you say, "Oh, they really care about my loved one, time to move on." I don't think so. These families want answers, to know that their loved one has actually died, and what went wrong so that the airline can make sure this never happens again. $28 million seems like a pretty fair price tag considering the knowledge that will be gained from all angles. Like someone else said...it's pretty easy for you to say this since your husband/wife, mother or father, or child's body isn't sitting at the bottom of the ocean.

The money comment is so insensitive. I don't care how much money they would have to spend - I would want my loved one back so that I could give them the respect they received while alive and during their life and that respect would not be sitting at the bottom of the damn ocean while I was handed a check for a few hundred thousand dollars!

Why is it that people seem to think money solves everything?? Well it doesn't! At least it would not for me - it would make not one bit of difference because my heart would be broken and there is nothing that could fix that at all - because that is love and I don't believe that is something you can buy.

I would not care if it they had spent 128 million dollars - someone would be answering my questions and telling me what happened and why in the hell I don't have my loved one to give a proper burial - because I would NOT be going away. The only thing that would stop me would be my own death. I would be absolutely consumed.

Consider the value of the information that might be discovered: If they do discover what happened to the plane, and discover some previously unknown technical problem with the type of plane, then so many more lives would be saved by averted future disasters. Even if the plane was brought down by lightning, analysis of where teh strike happened and how that damaged the plane severely enough to force it down might give some clues on how to better build airplanes.

wouldn't you want yo know what cause the airplane to go down ,so you can try to prevent it from takeing another 200+ lives?

Absolutely not. $28m is nothing compared to the life of just one passenger (and much less than the cost of a plane like, by the way, what doesn't even count). Highest priority is to find the reason for the crash to prevent it from happening ever again. 330's start crossing the atlantic dozens of times every day. The reason must be found. Period.

Remember: In the 1990's, two Boeing 737 came down and killed each time over 100 passengers, and were still flying, until the root cause was found (malfunctioning rudder control) in a third incident. Root cause analysis is not only worth millions, or billions of dollars - it is worth countless lifes and all of our safety.

Capiche?

It is very important to figure out what brought the aircraft down.

For example, if it were determined to be a design flaw, then other Airbus A330-203s that are vulnerable to experiencing the same accident could be fixed.

Whatever the cause, I would think that the families of the victims would like to have a definitive answer.

Well, if the SCOTUS can rule that the prosecutor of a case isn't liable for the performance of his deputies, how can an airline be held responsible for the error of one pilot? The pilot thing is not the same as the prosecutor thing, but they are going to say they are the same thing.

read post 9.3

I would imagine the families would care Jim. What if it were your wife or daughter/son?

I would consider my loved ones interred in the deep blue. Unless they called me.

That would be spooky...

It isn't really about the bodies, though I'd imagine some would like to bury them close by, if possible. It is mainly about studying the aircraft remains, and the black boxes if possible, in hopes of preventing a recurrance of this tragedy.

I would agree, but when you start breaking it down, it's really not that much money. Not to mention that the money isn't just being spent on bringing the bodies up and identifying them, it's also to find out why this happened and to see if it was something preventable...not just a bad decision to fly through a violent storm. Also, I know that I'd be fine with the body of say, my dad, lying at the bottom of the ocean because I know it's where he would want to be, but I know that my mother would not. The idea of the final resting place for my mom being at the bottom of the ocean makes me sick to my stomach. Plus, for me anyway, there is no price for having confirmation that my loved one has in fact died and it's not just speculation... A person needs that kind of confirmation to really "close the book" and move on in a healthy way.

YES! I was waiting for someone to say that.

Ben Linus moved the island to the Atlantic!

For transoceanic flights I think it would also be helpful to have an external beacon which detaches from the outside of the aircraft once the underwater pressure reaches a certain point (sort of like an airbag device), which in turn floats to the surface and begins to transmit its location once it reaches the surface. This beacon should also continuously records its own GPS location, too, once it is activated and reaches the surface. -

That would require the remaining fuselage to descend in an upright position to allow release. That is unlikely. It is the method used on commercial and some pleasure craft in some ways.

Actually Rick there are 3 separate devices to track when a plane goes down, one is the ELT6 Emergency Locator Beacon, and it can be set off manually or when it senses an impact, it has 2 antenna, one mounted on the dorsal area of the aircraft and one actually on the (Orange) box incase it gets separated from the aircraft, then you have the CVR and DFDAU. The cockpit voice recorder and the Digital Flight Data Acquisition Unit, both of these have locator beacons on them as well that go off as soon as either impact or submersion in water is sensed, but the batteries are only good for around 20-30 days depending on when they were last changed, which is done at regular intervals during heavy maintenance checks

The 737 is typically a shorter-haul airplane. The more cycles, the more pressurizing and depressurizing of the cabin. That sort of stress hastens metal fatigue. The same thing happened on a Hawaiian 737 a few years back and probably others I don't know about. You aren't likely to see that happen on a 747 that spends all of its time flying from LA to NY and back.

There is a phenomenon with aircraft radar (attenuation) that will at times show a squall line and clear beyond when in actuality the storm is fierce. The plane may have flown into what was looking like a short rain curtain when in actuality there was a tremendous shear that took the plane down.

When it comes to the so-called "coffin corner", if a plane can't fly below a certain speed then how the hell does it land or takeoff? Takeoff speed is much less than cruising speed. If an aircraft does slow too much it can experience some departure but that is also when a pilot adjusts trim and flaps to account for it or bumps the throttle. An aircraft just doesn't experience a sudden nose dive.

It has to do with the air density at altitude. An aircraft that can land at 140 knots at less than 6000 feet could stall out doing the same air speed at 40, 000. The controls will become mushy and the aircraft will become unresponsive, and then stall. At the other end, the plane can actually rip its wiings off! U-2 pilots had an istrument with a pair of needles and a ball, which they had to keep btween those needles. The ball represented the plane's airspeed, the upper needle, overspeed, and the lower, stall speed. I was told by a pilot that there were times when the needles bracketed the ball.

Clumsy; I would rethink your approach on groundspeed vs stall speed. You could have 0kts groundspeed and 150kts airspeed over the wing (unlikely, but possible), similarly, a sufficiently stiff tailwind could negate lift over the wing and cause your aircraft to stall. In fact, I've got pilot friends who've gone backwards (negative) groundspeed but they had a huge headwind keeping the wings producing lift. And vice-versa, you can exceed mach over the ground, but with no sonic boom because your aircraft has a heck of a tailwind and your airspeed is less than mach. Airspeed is the crucial factor, especially when determining upper limits for stress on the wings, stall speed, etc.

SaintGeorge: Aircraft can fly at lower speeds by changing the shape of the wing (flaps/slats) to increase lift. At higher speeds, these need to be retracted or a) they will cause more drag than lift; and b) you'll probably rip them off, which would make for an interesting landing (high speed). Aircraft can also manipulate their angle of attack (nose up/down) to increase lift over the wings, as well as use the power settings to adjust altitude. It's why the nose is up on landing and you often hear the engines spooling up/down slightly as the aircrew adjust the rate of descent as it's easier to do than adjusting flight controls.

Clumsy

Basically what he is talking about is that you have a maximum air speed, and a minimum air speed. At any given time, you have those two parameters (sitting on the ground waiting to take off, you have them as well). Those two speeds change depending on the flight control surface configuration (extending your flaps decreases your air speed as an example) as well as environmental factors.

As you increase your altitude, those two speeds start to converge. It is something that all planes that are pressurized encounter (I state pressurized because unpressurized planes are not designed to operate at altitudes where this is a factor). If you fly high enough, then the speed difference between these two limits might end up being around 25 knots. (I haven't flown in a very long time so I am not sure what the current minimum difference would be).

As for GPS calculating speed (which speed are we referring to, indicated or actual), yes it can be calculated from GPS readings, but I am not sure if the FAA has approved its use in this manner. It has limitations however so it would probably have to be used in conjunction with other instrument readings.

Boeing has also had issues with instrument readings relating to pitot tubes in the past. Look up the Air Peru accident off the coast of south america. If you are flying at night or at high altitudes, especially over water, you pretty much have no other option but to use instruments, looking out the windows for landmarks does you no good.

Jonathan

And just for those that dont know, the air data computer takes in air speed from the pitot tubes for airspeed, pressure readings from the static ports for altitude, temp readings from your total air temp sensor and angle of attack info from your aoa vanes, and in some cases information from the laser ring gyros that are used for your inertial navigation to. all of these parameters are combined to give the crew true air speed and altitude along with track, cross track, baro readings, mack limits, vertical speed indications on their vsi indicators and also to your ATC transponders and DFDAU (DIGITAL FLIGHT DATA ACQUISITION UNIT, all of this falls under their flight environment systems which is covered under chapter 34 of the FAA ATA Chapters.

Tech, from me, at least, thanks. My original specialty on the Phantom was what most people would call the fire control radar. I worked with the Instrument/Autopilot people enough to catch what you were talking about. It was educational. I'm really hoping they find out what the fatal flaw was.

Avionics Tech : Thanks!

Terry H-1988645 : I too was a "Fire control radar tech" on the Phantom II then transitioned to Radar/Com/Nav on the F/A-18.

All right! Been a while since I ran into another WCS tech! Navy, I take it? I was Air Force, '72- '92. What I saw of the Hornet's systems was pretty impressive. Nice bird.

@Terry H-1988645

Naval/.....Well sort of. USMC '77-92

All right! Hope you had a good run. I spent some time working with members of a recce unit out of El Toro, back in the early 80s. RF-4Bs. Good people, bad equipment; mostly leftovers from the Navy.

I'm impressed that it was a USA team out of Mass that found it.

You can't do this because heated elements will increase your chance of freezing by condensation and will give out false readings.

If your pitot tubes are properly designed you CAN do this. Any potential for false readings can be eliminated by temperature feedback devices to airspeed indicators. Let me guess, you work for ... h'mmm, Airbus?

"If your pitot tubes are properly designed you CAN do this."

Funny 3 of the 4 accidents recently involving pitot tubes were Boeing aircraft!

If I remember correctly in 96 2 planes (757) crashed due to freezing in their pitot: One was in Peru, the other one somewhere in central America.

A B-2 crashed in Guam in 2008 because it's tube clogged or condensation build in it.

Also, I think a 737 crashed in the 70 somewhere in the US for the same reason, leading a recall and change of all the pitot for the 727 fleet (Northwest airlines if I remember correctly).

Your faith in Boeing is clouding your judgement.

Thank you for pointing this out! No, I was not saying these things in defense of Boeing. All aircraft manufacturers need to ensure that these pitot tubes are fail safe, if only with the help of added redundancy. The most critical factor in flying is airspeed, so our ability to continuously and accurately measure airspeed really needs to be made fail safe. - RC

The pitot tubes and angle of attack probes are heated to 400 degrees fareheight on start for F-15s and F-111s (they are all gone, now :-( ). I have a permanent scar on my left hand from one such probe... The high heat is to instantly vaporize any water/ice and prevent icing conditions. I don't know whether general aviation pitot tubes have heating or if it's optional, but at the altitudes commercial airliners work at, I'd think heating would be automatic and mandatory before takeoff...

Doug

The pitot tubes and angle of attack probes are heated to 400 degrees fareheight on start for F-15s and F-111s (they are all gone, now

Thanks for pointing that out. I was getting ready to say the same thing. All Pitot tubes/AOA probes as well as rate gyros/etc are heated through necessity. In this case as in others either the heating element failed or the source for power to the heating element failed.

To clarify, the Pitot tubes, Static Ports, Angle of Attack Vanes, Total Air Temp probes all have heaters, either heating elements internal to the probes such as with pitot and aoa vanes, or heating gaskets such as used on the static ports. These heaters can be turned on manually on the ground or automatically once the plane is in the air and the weight on wheel switch isno longer engaged, and they all have redundancies. Everyone is focused on the pitot tubes but you also need pressure readings from your static ports which give your altitude and that pressure is calculated with airspeed in the air data computers to give your TKTS true knots and also your mach limits. there is the captians system, first officers system and the standby airspeed and altitude which does not go thru your digital air data computers. These systems also tie in to your cabin pressure regulators as well as a few other systems. The heating elements run of your DC ESSENTIAL BUS and also has back ups from your DC EMERGENCY BUS. Now even tho they say there was erroneous data sent from the transponder regarding airspeed, this could have been caused by a strong wind shear slamming the plane downwards causing a loss of forward momentum and there for a loss of indication from the air data computers causing the auto pilot to kick off and the flight warning computers to alert the crew, it would also make the air craft believe it was in an over speed condition requiring the crew to throttle back making the situation even worse.

The A-330 is so sophisticated and redundant that it will not let the pilots perform a maneuver or place a control in to setting that disagrees with the aircrafts flight configuration or flight envelope, if they try the flight warning computer gives a visual indication on their ECAM displays along with aural indications.. The ECAM display will display the proper steps to take to correct any issues the aircraft maybe having at that time. In most cases the newer generation of aircraft are smarter then the pilot6s that operate them and prevent accidents due to situational awareness, information over load or just tired air crews. it is nearly, and i do say NEARLY impossible to put the aircraft in to a configuration that would cause loss of control, the air craft will fight the crew to maintain a level and safe flight envelope.

I don't know anything about compensation but I do agree about the recovery efforts. Yes - the lady who continued to call her husbands cell phone and it continues to ring and she still believes he is alive. Her name.............it's Patricia Coakley and her husband is - Arthur Coakley. I wonder how she is doing with this new development. I wonder how they all are coping with this news.

I don't believe there are any words of comfort that are acceptable. My heart goes out to them.

That probably has more to do with the pilots rather than the plane. And chance to survive a crash resulting from an incident at altitude has nothing to do with the plane, it is more dumb luck than anything, though sometimes pure skill has a lot to do with it.

United Airbus 319 landed on backup systems, with minimal steering and braking ability, after the plane lost all electronics.Design flaw yeah right .It seem every time boeing makes the headlines Airbus comes back an takes the spotlight away from boeing.

Read more: #ixzz1IhrT0BLN

Solid state high intensity infared LED lasers might possibly be one solution which they can try out in the laboratory, too. They could also try flushing out these pitot tubes with high pressure (and high temperature) antifreeze, too. Just a couple of more suggestions. - RC