Any updates on the Airbus lost in the Atlantic?

Very interesting... That's a good way to display 2 channels of information and really the sort of thing I had imagined in my head. What kind of system is that if I can ask?

 

Its a Honeywell system. Its the same avionics that the MD-11 has. I think its called VIA 2000 but cant remember anymore.

Emergency alerts, Level 3, ( Immidiate crew awarness AND immediate corrective or compensatory action), Boxed Red with a triangle with words such as "APU FIRE". Master Warning light and Oral over the speaker. Then a light on the systems panel will light up telling you what system to view on the screen.

Abnormal Alerts, Level 2, (immidiate crew awareness with subsequent action), Boxed Amber with texts such as "BLEED AIR R TEMP HI" with master caution light and systems panel light.

Level 1 Alerts, Amber no box, system problem or maintenance write up, possible crew action or monitoring but no emergency checklist associated.

Level 0, (cyan) system status or operational such as "seat belts"

The nice thing is the checklist is worded exactly like the text in the alert so you can find it quickly.
The alerts are logically displayed to minimize the number of alerts requiring action. Additional alerts which occur as a result of the initial failure are displayed on the associated systems pages.
(I had to go into the book to find that last one, Im ready for my checkride now.)

The tough part for the pilot is knowing when and where to go into the checklist for Emergency non alerts. Those are problems that have no associated alert on the screen. Such as "airspeed lost or erratic" or "Engine failure/in flight shut down". Say your crusing along and one of the engines slowly winds down and your looking out the window wishing your flight attendants werent old and fat and all of a sudden you see all these amber alerts all over your screen, bleed air and generators and busses and all kinds of stuff. It could take a minute to figure out what happened to cause all of that and what checklist you need to pull out.

 

Here is some info from the interim report issued today.

http://www.flightglobal.com/articles/2011/05/27/357307/af447-stalled-but-crew-maintained-nose-up-attitude.html

 

-A bit- more info New York Times. http://www.nytimes.com/2011/05/28/world/europe/28flight.html

Sounds like those guys were totally confused.

Edit: BEA Report http://www.bea.aero/fr/enquetes/vol.af.447/point.enquete.af447.27mai2011.en.pdf

 

Thats what it sounds like to me.

 

But why? There's more to the story. The pilots wouldn't intentionally climb at 7,000 ft/min after a stall warning.

 

Oh there is a lot more to the story ; however, They were apparently in a massive thunderstorm with potentially massive updrafts then the autopilot gives up and sais "hey I cant hold altitude anymore, so you fly it" and they subsequently go to max power, thats the only way they are gonna get a 7000 foot per minute climb rate at that altitude and that weight. If they were at 38000 feet (most likely way to high for their weight) they would have been in "coffin corner" and in severely rough air a stall would have been inevitable. An airline pilot who allows a large, heavy, swept wing jet to stall at 38000 feet has just assumed the roll of Test pilot and most airline pilots are not Test Pilots.

 

Jerry, can you 'splain this one to me?

At somewhere around 37K feet? (Edit: I know WHAT it means... I don't know WHY. I'm trying to figure out what these guys were thinking.)

 

Outside the realm of Tower Control as they were, it was sheer folly not to route around a thunderstorm that tall?

They could see where they were going, on the cockpit radar???

Does this data support or refute the theory the tail broke off?

Thanks guys...this is all very interesting until you recall the passengers aboard, then it's just sad. It's also interesting to me that so soon into the flight time the Captain would need a rest, anyone comment to that?

Other than a hard night in Rio or something....

 

Well who knows what they were thinking?? Personally I think they were so frazzled and confused or they just could not "believe" this was happening that they made the situation worse by throwing all the basic stall recovery stuff out the window. If you are in Extremely rough air, at night and you can hardly see the instruments, rain hitting the windshields and all sorts of warning horns are going off it could be extremely confusing. One thing that I can mention in their defense is that when you stall a large jet you dont just shove the nose over, typically you are trained to just "relax" the pressure on the yoke and go to max power and then fly out of the stall, most of the time if you do it right your pitch attitude will still be positive and as long as you keep the wings level the engine power will take you out. At those altitudes however your engines are already pretty close to putting out max power anyhow so they probably didnt have alot left to play with. And we dont do stalls in the simulator at 37000 feet either.

 

Yea thats not uncommon at all, he would go to rest a few hours into the flight then comback after a few hours rest. If i was Captain on that flight; however, I certainly would not have left the cockpit knowing there is bad weather ahead.

 

thanks Jerry. -- And Tex... please don't bait the kooks.

 

Sorry.

That was rather what I was getting at though actually.

"We are just getting ready to travel thru a dead zone in international radar coverage, there's a storm front 40K feet tall or higher dead ahead......I think I'll leave it to these youngsters."

I do understand the iced pitots could have caught everyone out.

I was once on the copilots seat (just riding ) on a Charter Flight (over the US) where the pilot requested to "Shuck and Jive for weather" from flight path and his eyes stayed glued on the radar for the next hour, dodging the red zones on the screen.

I know big jets don't do it that way. (Beechcraft Baron...nice plane)

 

When I got my type rating in the Learjet (back in 1990!), part of the sim training was to do stall recoveries at FL410. Unlike at low altitudes, you can't power out of it-- you must lower the nose significantly, and you will lose 500-1000 feet of altitude, at a minimum.

I did them again in the sim a few years ago, when the other pilot mentioned he was nervous about low speeds at high altitude (a perfectly reasonable thing to be nervous about!).

Imagine the situation for these poor guys-- bumping around in moderate to severe turbulence, at night, instruments going nuts, warnings all over the place... not a place I'd like to be.

Without knowing what really went on, the unfortunate thing is that they should have focused on pitch and power, and just rode it out. However, that's easy to say from the comfort of my office.

 

Actually, they do it exactly that way. No one intentionally flies through a thunderstorm, with the exception of some research guys.

 

There was a Northwest 720 that crashed in the Everglades in 1963 shortly after taking off from MIA. It was trying to skirt around a thunderstorm when it got caught in a vicious updraft. As the nose kept rising, the pilot kept feeding in more nose-down stabilizer trim -- and then the aircraft hit an equally vicious downdraft. With that much nose-down trim, a dive was inevitable, and it didn't stop until the aircraft hit the ground. The pilots kept pulling back on the stick but all that did was to eventually cause the stabilizers to fail structurally. (Another flight in a similar predicament got out of it by actually applying more engine power. This resulted in the nose rising and the dive lessening until the pilots could regain control.)

Anyway, it sounds like this scenario - updraft, then downdraft - might have been a factor here, though it reads as if the Airbus remained nose-up right up until impact.

 

Refutes it.

 

The problem here is that the automatic trim was lost when they went to "alternate law". This left the trim set to where it was just before they stalled. Which was in a nose up condition. If they just relaxed pressure, it may not have done much good. The reason is that without the trim rolled forward it the elevator response is limited. They likely needed to trim the nose down AND apply forward stick and that obviously didn't happen.

In this case it is hard to figure out if they recognized that they were stalled. If they didn't they may have netrualized the controls, but due the nose high trim the aircraft wouldn't likely recover. According to the report, at one point they commanded nose down pitch and the aircraft got to the point of giving them another stall warning. Not sure if the pilots misinterpreted that warning horn. If you pushed the stick and horns start going off you might tend to stop pushing. Problem was they were in a deep stall at that point and they should have kept pushing.

Parts of this crash are errily similar to what happened in the Air New Zealand A320 near Perpignan on Nov 27th 2008. In that incident the pilots didn't recognize that the nose needed to be trimmed down to recover from a stall once the aircraft computers dropped off line. They approached stall and the approach to stall caused the airspeed readings to not agree, so the flight control computers dropped off while the trim was set nose high. The ANZ pilots then applied power and the application of power resulted in an additional pitch up moment that resulted in a subsequent stall. That occurred at an altitude too low to recover.

Airbus has subsequently amended their stall recovery procedures. They recommend applying nose down pitch commands without adding power until the stall is recovered and then power is supposed to be applied. The upshot is when these aircraft are stalled adding power isn't going to do you any good, you need to get the nose down to recover.

Unfortunately we just won't ever know what they were thinking.

 

We might when BEA releases the CVR data.

 

So the passengers could sit there and look at their monitors and see they were right in the middle between Brazil and Senegal, and then things go wrong and they experience a 3+ minute free fall down to what they know is absolutely nowhere should they survive.

What a grim way to go :-/

 

Reuters is the first to ask the obvious question... what were these guys thinking?

Air France crash sparks pilot mystery http://www.reuters.com/article/2011/05/27/us-france-brazil-crash-idUSTRE74Q28420110527

The story ends with the thing that keeps gnawing at me....

I wondered above if the guys were so busy looking at the warnings they quit flying the airplane. I still wonder... cuz I can't make any sense of their actions.

 

They basically have:

http://www.cbsnews.com/htdocs/pdf/point.enquete.af447.27mai2011.en.pdf

 

This is what doesn't make sense to me:

"At 2 h 10 min 51, the stall warning was triggered again. The thrust levers were positioned in the TO/GA detent and the PF maintained nose-up inputs. The recorded angle of attack, of around 6 degrees at the triggering of the stall warning, continued to increase. The trimmable horizontal stabilizer (THS) passed from 3 to 13 degrees nose-up in about 1 minute and remained in the latter position until the end of the flight."

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Why would they trim like this and fight it?

 

Seems like it could be a combination of ice (maybe a lot of ice), bad speed information and a rearward shift in cg.

 

Yes it doesn't make sense.

One scenario, that might make sense is that maybe they heard the first stall warning, the airplane stalled, but then the stall warnings went away (because the AOA sensors were in a fault regime). At that point they are falling like a rock, but don't realize they have stalled and are falling. Maybe they thought that they weren't stalled after the horns stopped blairing at them. Then the horns came on again, and they didn't know what to think.