The Last Four Minutes of Air France Flight 447 - DER SPIEGEL 2/25

[Call Me Wesley]

I just read this in the magazine, and it's covering what led to the crash of Air France Flight 447. For the ones who don't remember, this happened: http://en.wikipedia.org/wiki/Air_France_Flight_447

Death in the Atlantic
The Last Four Minutes of Air France Flight 447

DER SPIEGEL/Gerald Traufetter 2/25/2010


The crash of Air France flight 447 from Rio to Paris last year is one of the most mysterious accidents in the history of aviation.
This photo shows oxygen masks that were recovered from the sea.

The crash of Air France flight 447 from Rio to Paris last year is one of the most mysterious accidents in the history of aviation. After months of investigation, a clear picture has emerged of what went wrong. The reconstruction of the horrific final four minutes reveal continuing safety problems in civil aviation.

One tiny technical failure heralded the impending disaster. But the measurement error was so inconspicuous that the pilots in the cockpit of the Airbus A330 probably hardly noticed it.

Air France flight 447 had been in the air for three hours and 40 minutes since taking off from Rio de Janeiro on the evening of May 31, 2009. Strong turbulence had been shaking the plane for half an hour, and all but the hardiest frequent flyers were awake.

Suddenly the gauge indicating the external temperature rose by several degrees, even though the plane was flying at an altitude of 11 kilometers (36,000 feet) and it hadn't got any warmer outside. The false reading was caused by thick ice crystals forming on the sensor on the outside of the plane. These crystals had the effect of insulating the detector. It now appears that this is when things started going disastrously wrong.

Read full article here.

[wtmusic]

1. Fascinating.

The computer/human interface seems to be the problem here.

[Barack_America]

2. Not unlike the problems a certain car manufacturer is currently experiencing, no?

Have electronics become too complicated?

That really was a fascinating article. Hardly reassuring, but fascinating.

[Call Me Wesley]

14. In the Airbus' case, yes.

You not only need to be a pilot but also a software engineer.

[Call Me Wesley]

6. This is always the case with the Airbus.

I posted this some time ago: http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=389x6192724

[Blue_Tires]

13. I *really* hope they get every bug worked out of the B-787

which is going to be fully wireless...

[Angleae]

42. So is a 777.

I'm more worried about the current return paths on a 787 than it being fly-by-wire.

[Heidi]

33. Rail companies have been criticized for similiar problems.

Not good to take all or most decision-making capacity away from trained pilots and engineers, however cost effective it may seem to the CEOs and bean counters. Passengers are stakeholders, too.

[wtmusic]

46. Not only decision-making, but experience-building

Sitting in a chair chatting with the copilot, while auto flies the plane, does nothing for a pilot's skills.

[muriel_volestrangler]

3. Wow, that's quite frightening

Because it doesn't sounds as if much has yet been done to prevent it happening again on an Airbus.

[Call Me Wesley]

7. Exactly.

What's the most frightening here I think is that obviously none of the passengers knew there was an emergency. They just hit the water by surprise with 36 g.

[Fumesucker]

4. The last two paragraphs of the piece..

For several years now, Airbus has offered its customers a special safety program - called "Buss" -- at a cost of €300,000 per aircraft. If the airspeed indicator fails, this software shows pilots the angle at which they must point the plane.

Up to now, Air France has chosen not to invest in this optional extra for its fleet.

An optional safety program that costs three hundred thousand Euros per aircraft?

[Barack_America]

5. Right? That's like buying a car with brakes "optional".

[Angleae]

41. No, it's like buying a car with anti-lock brakes optional. Normal brakes standard.

[Call Me Wesley]

8. It's ironic. Or cynical.

Cynical that it's about the money, and cynical that such a safety device is 'optional' instead of a basic implementation. I think I fly with Boeing in the future.

[RamboLiberal]

9. Thanks for posting - I look forward to reading

I've always been fascinated with reading the investigations of air crashes & other catastrophic failures whether mechanical and/or human and the lessons learned.

[Call Me Wesley]

10. Not many lessons learned yet, at least not by Air France, unfortunately.

It's a good but also scary read; there was a lot going wrong there.

[BrklynLiberal]

11. What makes this tragedy all the more tragic is how avoidable it was...at so many different times

and at so many different levels..from pilot decision to airline policy to bureaucratic bullshit at the very top governmental level.

Those "optional safety" measures should have been requirements.

[Call Me Wesley]

17. Totally agreed.

'Optional' safety should be a basic must.

[Barack_America]

23. It seems like the pilot's decision was the result of airline bureaucracy.

I may have to rethink my preference for nonstop flights after this.

[Blue_Tires]

12. wouldn't icing in the pitot tubes be a potential issue for any aircraft?

i'm not trying to dispute; i just think this story is kind of speculative...

[Call Me Wesley]

16. It is, but with the computer hierarchy on an Airbus,

it's a real problem. Boeing has the same problems and they were reported, but the pilots could handle it:

Pitot tubes sometimes also fail on Boeing aircraft. When SPIEGEL contacted the American Federal Aviation Administration, the body which oversees civilian flight in the US, the FAA confirmed that there had been eight such incidents on a Boeing 777, three on a 767, and one each on a 757 and a Jumbo. Boeing is currently conducting a study on the safety effects of "high-altitude pitot icing on all models in its product line," says FAA spokeswoman Alison Duquette. The FAA did not, however, identify "any safety issues arising" during these incidents.

Could it therefore be that the flight computer, which is hard to manage in emergencies, actually contributed to the loss of control by the Airbus pilots? Air-safety experts Hüttig and Arnoux are demanding an immediate investigation into how the Airbus system reacts to a failure of its airspeed sensors.

[Blue_Tires]

21. ugh...The Airbus board of directors meeting probably isn't a fun place right now

I know this story is a theory that fits the facts, but devastating if it is proven to be true...The stakes on finding the data recorder just became that more important

[Xithras]

15. It's probably a good thing that the passengers didn't know it was coming.

I know that, when the plane crashed, there was a lot of speculation about whether passengers could have survived the breakup, and how terrifying it would be to plunge for several minutes knowing you were going to die. In a way, there's a small bit of comfort to be taken from the fact that the plane stayed intact until impact, and that nobody outside of the cockpit was aware that the plane was going down. Their passing was instantaneous and without warning.

[Call Me Wesley]

18. Sad fact is, that probably not even the most experienced pilot on the plane,

the captain himself, was aware of it. Most likely, the most inexperienced co-pilot was then sitting in the captain's chair. The captain was found with other victims. The two co-pilots, belted to their seats, are on the ground of the Ocean there.

[Hawkowl]

24. Common irresponsible practice

Airlines have to have multiple crews to do long over water flights. A pilot can only be in the cockpit seat for 8 hours. The loophole in the regulations allow these flights to have one Captain. So while over the ocean it is usually two co-pilots (First Officers) that are sitting in both pilot seats, while the captain is sleeping in a bunk in the back. Why not simply have two completely qualified Captains who can trade off shifts? Because the airlines ARE TOO FUCKING CHEAP! The cost difference would be no more than a couple of thousand dollars per flight.

I have no doubt that if a more experienced pilot, like the 58 year old Captain sleeping in the back, had been at the controls, this disaster could have been averted.

1) You should be able to fly without any airspeed indications. It is very difficult but doable.
2) The thunderstorms should have been avoided, and it is likely the inexperienced co-pilots made a stupid decision to try and bob and weave through them. A highly experienced captain would have avoided them at all costs even if doing a 180 degree turn and diverting to a different airport for fuel. I have done so in the past.

3)All Airbuses do NOT allow the pilot to simply disconnect the computer and engage some sort of manual reversion. However, in extreme situations, the computer "throws in the towel", as the article says, and dumps everything back on the pilot. However, now the airplane flies completely differently than the pilot is used to. So now a lot of the experience the pilots have in their particular type of Airbus becomes WORSE THAN USELESS. Why? Because now you have to consciously override your instincts because you are essentially flying a different airplane without the computers engaged and you have never been allowed to practice on a daily basis. Most airliners (Boeing, Embraer, Bombardier) have less integrated autopilots that allow the pilots to disconnect them every day and practice flying manually. (It is more fun! And it is essential to maintain your skills for those times when the "computer throws in the towel".) It never fails that the times when you want the auto pilot on more than anything in the world, it simply can't fly as well as a human.

All aircraft accidents are a chain of multiple failures. The accident is preventable if only ONE link in the chain is broken. Sadly, the Air France accident completed its chain of fatal errors.

[Call Me Wesley]

27. Yes.

You know the airlines companies' great dream: A computer flying the whole thing, with no expensive pilots anymore and perhaps a roombla who keeps the cabin clean. Self-service for the passengers as well. Lufthansa pilots just went on strike this week because of that, and they were mostly replaced by other 'cheaper' pilots from other airlines Lufthansa owns.

[Hawkowl]

32. Dream is the right word

The decision making skills required to fly an airplane is just way beyond any computers in existence. However, I do see the move to "drone" flying passenger planes in the next 20 - 30 years. Being a pilot, I wouldn't mind this so much, since I hate being away from home anymore. I could just fly the plane at my desk in my robe and slippers while taking a break to post on DU!

[Call Me Wesley]

39. LOL!

But you know you'd be outsourced. I once had Microsoft Flight Simulator, so I'd take over your job. My joystick skills outmatch your robe and slippers skills. ;)

I'd never get on a plane where no pilot would be around.

[EFerrari]

19. Malcolm Gladwell talks about plane crashes and little problems

that turn into crashes in this presentation re "Outliers". I'm not sure he isn't full of bs but it's an interesting story well told:

http://www.c-spanvideo.org/program/282899-1

[Call Me Wesley]

20. Thanks for posting.

Will have to watch it later.

[Statistical]

22. Still a lot of unanswered questions.

Pitot tubes icing have been a known issue for almost a century now. The difference between static pressure and impact pressure is the only way to know how fast you are going in the air. As long as there have been pitot tubes they have iced up. So a pitot tube failure although bad isn't unprecedented.

However this:
One alarm after another lit up the cockpit monitors. One after another, the autopilot, the automatic engine control system, and the flight computers shut themselves off. "It was like the plane was having a stroke," says Gérard Arnoux, the head of the French pilots union SPAF.

WTF? A loss of air speed information should not cause the flight computers to freak out like that. That compounded are already complex and dangerous situation. Complete loss of flight computer is the second worse thing that can happen in the air. The first only being catastrophic airframe damage. Having an engine fail is better than losing flight computer.

Why Airbus would design a flight computer to react to the situation so badly is beyond me. Had the flight computer stayed "rational" it is entirely possible the crew could have gotten control of the plane.

[Call Me Wesley]

25. I agree,

and in the end, what they really want is to just have a computer fly the entire plane. No costs for pilots anymore. Obviously, the computer just went on strike, or stroke mode. And you can't shut it down on an Airbus. On a Boeing, you can.

[MicaelS]

29. I guess a dumb question is in order...

Why don't pitot tubes have heating elements for de-icing?

[BrklynLiberal]

31. Wow! What a concept. It would appear that someone, somewhere has been very negligent about this

I would guess that someone does not want to have to spend the money to make the changes.

Aerospace experts have long known how dangerous it can be if the airspeed indicators fail because the pitot tubes ice up. In 1998, for example, a Lufthansa Airbus circling over Frankfurt Airport lost its airspeed indicator, and a potential tragedy was only averted when the ice melted as the plane descended. At the time, German air accident investigators at the German Federal Bureau of Aircraft Accident Investigation (BFU) in Braunschweig demanded that the specifications of the pitot tubes be changed to enable "unrestricted flight in severely icy conditions."

As early as 2005, the French aerospace company Thales, which manufactures the pitot tubes used on flight AF 447, set up a project group called Adeline to search for new technical solutions to the problem. According to a Thales document, loss of the airspeed indicators "could cause aircraft crashes, especially in cases in which the sensors ice up."

Aircraft manufacturer Airbus was well aware of the shortcomings of the Thales pitot tubes. An internal list kept by the airline manufacturer shows there were nine incidents involving them between May and October 2008 alone.

More than two months before the Air France crash, the issue had been raised at a meeting between Airbus and the European Aviation Safety Agency. However, the EASA decided against banning the particularly error-prone pitot tubes made by Thales.

In fact, the problem with the airspeed indicators lies far deeper. To this day, the relevant licensing bodies still only test pitot tubes down to temperatures of minus 40 degrees Celsius (minus 40 degrees Fahrenheit) and an altitude of about 9,000 meters (30,000 feet). These completely antiquated specifications date back to 1947 -- before the introduction of jet planes.

[Statistical]

34. They do.

Sometimes the severity of the freezing can overcome the heaters.

[MicaelS]

44. OK, thanks n/t

[TexasObserver]

26. Recommend

[Call Me Wesley]

37. Thank you! (nt)

[malaise]

28. What an awful way to die

:cry:

[BrklynLiberal]

30. Yes....The horror

[Call Me Wesley]

38. According to the findings,

it was pretty quick. Nobody on the plane saw it coming, and then it hit with 36 g. Some of the passengers who had the belt on were cut in half by it. It was death by surprise, because of the heavy turbulences of the whole flight, no one could make the difference from flying straight ahead or diving down at full speed.

[amborin]

35. aside from the pitot tube issue, was the route issue

if you read Tim Vasquez' website, it lead one to believe the trajectory was right into the storm

whereas other flights deviated considerably

there is also the issue of correctly reading the radar...needing to point it fully downward on high gain

also----to what extent is AF culpable in exerting time pressure? its flight to Toronto, which nearly crashed, was the only flight that continued its landing.......

[Call Me Wesley]

36. Some pilots outfly the bad weather there,

this captain didn't load enough fuel to do it to save expenses. If he would have flown around the bad weather, he would have had to land in Lisbon, which wouldn't have made the company very happy. It's all about the money in the end.

[amborin]

40. the lufthansa and iberia flights deviated considerably....

yet landed at their ultimate destinations

i only meant deviate around the CBs

[wtmusic]

47. I believe that's the primary cause.

You can have a pitot tubes that don't ice, avionics that function perfectly. But if you fly into bad weather in the middle of nowhere, you're asking for it.

[Withywindle]

43. And that sort of thing is why I'm a nervous flier.

I'm not really afraid of terrorism - what are the odds?

I'm afraid of airlines cutting corners to save money in ways that compromise safety. And this isn't a manufactured threat: it's very real and happens ALL THE TIME.

Edit: And I had the idea that most other developed countries' airlines were better about this and therefore safer than American ones. :(

[ParkieDem]

45. I see it differently

Having worked for an airline, I can assure you that they are OBSESSED with safety. They have to manage costs like everyone else, but no airline will scrimp on safety to save a few bucks. There are other areas where costs can be contained.

Airline travel is extremely safe. In 2009, there were 0.7 accidents per MILLION flights. Between 2007 and 2008, there were a grand total of zero fatalities on US airlines. Is there always room for improvement? Sure. But our system is pretty damn safe.

[wtmusic]

48. Exactly. Your chances are far worse driving

than flying on a commercial airliner.

Private planes are a different story.

[Blue_Tires]

49. ttt