Air France Flight 447

[CAPChief]

What amazes me in this story is that the airline pilots did not recognize a stall condition, and execute a drill that should be second nature to them.

Nose down! Add power!

http://news.yahoo.com/air-france-captain-woman-flight-447-trouble-214157897--abc-news-topstories.html

[bflynn]

I think most pilots can't understand it.  The only slack I can cut for the crew is that it was over the ocean, in pitch blackness and there isn't any real feedback in the controls.  I understand he was doing what Airbus pilots were taught to do - power out of a stall.  I believe they've since changed that recommendation.  It's difficult to imagine this happening in a GA airplane, but a larger plane is a different beast.

What I find scary is that they tested other pilots under similar conditions and almost all of them figured out what was happening before they crashed.  Why not all of them?

[abdsp51]

Most commercial flights are spent on autopilot and there was research done to show that most flights have very little hands on flight time.

[lordmonar]

Well...that the difference between simulator and real world.

When you enter a simulator....you KNOW you are going to get some suprises so you are on alert for them.

Halfway through a trans atlantic....the cheif pilot just going out for his crew rest.......then the fecal matter hits the fan......insterments not working, [censored]ing Betty yelling at you, sometime you just don't recognise the key symptons and go down the wrong troubleshooting path.

As a comm maintenance guy.....I see this sort of stuff all the time.  Mission critical circuit down.....you get going down the wrong path and wast valuable time chaseing ghosts or worse introducing new problems into the system that masks the real problem.

I hate the Head Line of the article!  It implies that the captain was stooping the flight attandant in the bathroom or something instead of doing his job....because it took a minute for him to get the cockpit....and he was travelling with a flight attandant.

It does say that they don't know for sure.....but you can see the "but" written between the lines.

[abdsp51]

I find it interesting that they are threw in the lack of feedback due to the fly-by-wire system that Airbus uses.  It's a proven system and looks to me like they are trying to fault technology instead of inadequate training and supervision.  Everything I have seen on this seems to point to crappy weather, crappy training, inexperience and lack of supervision.  It will be interesting to see what the final determination will be.

[Cliff_Chambliss]

Don't leave out the lack of interconnected flight controls.  With the side stick there is not a lot of movement and as each stick operates independently of the other the pilot in the left seat could be pushing his stick forward and the right seat pilot pulling back and neither aware of what the other is doing.  YA GOTTA COMMUNICATE.  There is no easy answer to this, crew resource management, communications, situational awareness, equipment hiccups, there were several casualities that night.

[denverpilot]

There was also significant portions of the CVR recording that were edited out of the official report.

The government representatives were squirming recently when someone leaked the relevant portions to the media. Made the pilots look even more lost/confused/untrained. 

Airbus and the French government being highly intertwined, and Airbus having put in a very poor showing to sell jets to the Chinese last year, the motivational conflicts of interest are showing.

Nobody wants anybody asking any tough questions.

Meanwhile, at the end of the day, the pilots never reverted to basic instrument attitude flying. There was always a thrust lever position and a pitch angle that would have kept the aircraft flying and recovered it from the stall.

Flight Idle was not that thrust lever position.

[a2capt]

I've heard from many sources, that not only are they not interconnected, and lack feedback, but the input from both sets of controls are averaged so if one is full forward, and the other is full backward, the end result is neutral.

Seems asinine to me. But.. if that's how they are.. it all points to training and communication, to me.

[simon]

AF447 will go down as the primary case study for the pitfalls of automation in aircraft, especially how software drives the flight controls, as well as the important of unusual attitude training.

There was a Grand Canyon sized disconnect between the assumptions made by the aircraft designers and the training actually given to the pilots.

As for the initial cause of the problem, the frozen pitot tubes, this had been formally reported countless times prior to the crash. Wait for the cover up. It was a known problem with a documented "advisory", but Airbus knew the ramifications of grounding the aircraft worldwide. Air France agreed and had replaced some, but not all, of the faulty tubes. The rest is history.

It is interesting to me, that when all hell breaks lose and the avionics software can't make sense of what is going on, that it reverts to "Alternate Law", a different set of rules, all the way down to when it really hits the fan and the avionics revert to "Direct Law", where the flight controls make the aircraft behave like, ironically, a Boeing. Unfortunately, the pilots had never undergone unusual attitude training under some of these modes, which is where they found themselves when the tubes froze over. Read about the Airbus flight modes here (http://www.airbusdriver.net/airbus_fltlaws.htm) and tell me if a pilot undergoing a helmet fire when his cockpit lights up like a Christmas tree can rattle off which mode is for what condition. (Incidentally, the software didn't work as designed - no surprise there - http://www.flightglobal.com/news/articles/stalled-af447-did-not-switch-to-abnormal-attitude-law-357394/)

The Boeing pilots I have spoken with really do not like the fundamental design principles behind the Airbus. The Airbus pilots I have spoken with think the design is pretty cool - great automation. Maybe they are both right, to a degree. Maybe it depends on whether one is going through regular day to day legs across the country or whether it has all hit the fan.

[a2capt]

..and lets not forget about this:


Airbus A320 crash at Habsheim airshow, France 1988
http://www.airdisaster.com/investigations/af296/af296.shtml

Interesting though, I'll admit, I will try and book a ticket on an airline that uses solely Boeing equipment first, however I realize that's not a practical answer, I also know the things are not all just falling out of the sky, statistics show that my travel to the airport for for that flight is a lot more dangerous. You would just think that after years of knowledge, they would identify the weak links here.

[denverpilot]

I've heard from many sources, that not only are they not interconnected, and lack feedback, but the input from both sets of controls are averaged so if one is full forward, and the other is full backward, the end result is neutral.

I believe this is a rumor that's floating. One Airbus Captain I spoke with said there's a selector for Pilot Flying and Pilot Not Flying and the other side is locked out by that selector. Another report I read, indicated what you're saying about averaging. Indont know what to think.

On another forum we've had a number of discussions about some other characteristics too, like the fact that the side stick in Normal Law is limited by the flight control computers. "Full" deflection of the stick doesn't give full deflection of the controls.

Also the controls are more like a setpoint not a continuous input type of thing. No control pressures. You push to the left a bit and release and the aircraft holds the bank angle "selected".

Since rates are automatically limited, and its a "return to center" spring loaded type of joystick, that leads to pilots just kinda flicking it around like a video game.

A good example is in this video which I like a whole lot, but some don't care for the music...

After you watch it for the great views... Run it again and carefully watch all the flopping/flicking full-deflection joystick inputs in the shots where you can see the Captain's hand.

It goes against all the laws of Primacy taught flying other aircraft where you push and hold pressures, which is interesting. Way closer to a video game than any aircraft with direct connections to the control surfaces.

Like any aircraft, you have to know your ship and systems. The disconnect here is that it doesn't appear the Air France crew was allowed to see very far behind that magic software curtain...

The video...
http://www.youtube.com/watch?v=nYDba1UsgHc

(Also imagine what a U.S. company would do to a Captain who made such a video.  "Against policy" and all that.  Personally I think it's great this Captain bothered to shoot and edit his video. It lifts that Oz-like man-behind-the-curtain mystery for passengers and pilots who'll never fly "big iron". Just a guy/gal flying an airplane...)

[Critical AOA]

As a long time aviation maintenance professional and current maintenance controller for an airline I can attest that a very large percentage of airline pilots do not have a good understanding of the systems on the aircraft they fly.  The more complex the aircraft, the less they understand.  Airbus are overly complicated and are far more prone than Boeings to overwhelming the pilots when something goes wrong.  Take a look at the Qantas A380 that had the engine let go and damaged fuel lines and electrical harnesses.  They had a couple extra captains in the cockpit and it still took them quite awhile to figure out what all their problems were.  Not a good thing.