The story of Air France Flight 447 (June 1, 2009)

I don't understand how your comment relates to my post.
Agreeing with you and adding that I’m sure the crew could have accurately answered a question about how to respond to the events if asked but when it actually happened they were startled and froze. One pilot full back, one full down and they rode it into the ocean.
 
..so how many of you have had to revert to pitch and power in real life due to issue with the pitot static system?
 
..so how many of you have had to revert to pitch and power in real life due to issue with the pitot static system?
I had a static port freeze on takeoff in a Hawker…saw the altimeters do weird things when I rotated. fortunately it thawed itself out before my first level-off, but pitch and power got me there.

I’ve had a couple of light airplanes with pitot or pitot heat problems, and it wasn’t unusual in my glider days to realize there was water in the system on the first flight of the day.
 
Two frozen pitot tubes hard IFR. Lots of sim emergencies. And a couple, well, let’s just say self induced issues and leave it at that!

EVERY time it made the issue a non issue.
 
..so how many of you have had to revert to pitch and power in real life due to issue with the pitot static system?
I had a IAS DISAGREE, ALT DISAGREE, and ECC messages in a 737-700 a year, or so, ago. They replaced the right AoA sender, right ADIRU,and right FCC to fix it.

We were at cruise at night when it occurred. It started with the IAS DISAGREE (appears below both airspeed tapes) but went away as we started the checklist. Several minutes later it came back. Picked up the checklist again but, before we could finish it we also got the EEC light (electronic engine control). We stopped the IAS DIAGREE checklist and actioned the EEC checklist which had us switch to the alternate EEC mode. Then, back to the IAS DISAGREE which was soon joined by the ALT DISAGREE message. We completed those checklists. The split between primary airspeeds and altitude values started small but grew throughout the rest of the flight. Once the splits were large enough, it became clear that the right-side data was good and the right-side data was not. Eventually, the right airspeed indication dropped to the minimum value, 45kts, and the altitude discrepancy was a bit over 400'.

Obviously, until we have determined what data is good and what is bad, we fly pitch/power.
 
Ahh.. I thought maybe he genuinely goofed around with the pitot system and blocked something after you did the preflight
 
..so how many of you have had to revert to pitch and power in real life due to issue with the pitot static system?
My instructor had to do that on one of my private-pilot lessons. The plane had a flap over the pitot tube, which had a vane that was supposed to open it when there was enough airspeed. It failed to open during takeoff, so he took the controls and brought us around for landing.
 
My instructor had to do that on one of my private-pilot lessons. The plane had a flap over the pitot tube, which had a vane that was supposed to open it when there was enough airspeed. It failed to open during takeoff, so he took the controls and brought us around for landing.
Damn. I always wondered about those little pitot flaps..
 
My instructor had to do that on one of my private-pilot lessons. The plane had a flap over the pitot tube, which had a vane that was supposed to open it when there was enough airspeed. It failed to open during takeoff, so he took the controls and brought us around for landing.
I also had that happen when I was a student. My instructor recognized it as a teachable moment and had me bring it around for landing.
 
Basically, flying like an airline pilot means they had no clue as to what the full stall behavior of a swept wing aircraft is like.

I still remember the full aft stick stall in the T-38. I had done lots of full stalls in aerobatic aircraft before.

But the the nose never went below the horizon. It was quite stable. Just some wing rock. And a WHOLE of going down. It solidly pegged the VVI at over 6000 fpm down.

I did mine over a cloud deck so go to see the TREMENDOUS "ground" rush.

From previous articles, the one pilot did have the stick forward, but he did not have control. And with the sticks no interconnected, they did not realize they were doing different things.
 
Basically, flying like an airline pilot means they had no clue as to what the full stall behavior of a swept wing aircraft is like.

I still remember the full aft stick stall in the T-38. I had done lots of full stalls in aerobatic aircraft before.

But the the nose never went below the horizon. It was quite stable. Just some wing rock. And a WHOLE of going down. It solidly pegged the VVI at over 6000 fpm down.

I did mine over a cloud deck so go to see the TREMENDOUS "ground" rush.

From previous articles, the one pilot did have the stick forward, but he did not have control. And with the sticks no interconnected, they did not realize they were doing different things.

One pilot did have his stick full forward. The other had his stick full back most of the time. In addition the stab auto trimmed nose up as the aircraft decelerated during the initial pitch up. The A330 sums the stick inputs so with one stick full down and one stick full up you get neutral elevator. With the stab trimmed full nose up the aircraft was not going to recover. The copilot who held his stick back was ab-intro trained with very little stick and rudder time.
 
Did either pilot attempt to use the sidestick priority button?
 
One pilot did have his stick full forward. The other had his stick full back most of the time. In addition the stab auto trimmed nose up as the aircraft decelerated during the initial pitch up. The A330 sums the stick inputs so with one stick full down and one stick full up you get neutral elevator. With the stab trimmed full nose up the aircraft was not going to recover. The copilot who held his stick back was ab-intro trained with very little stick and rudder time.

Except that due to the iced up pitot tube, the system reverted to another mode and full command of the surface (like most planes) was based on the stick with command.

Normally, the system commands a performance. But when the system reverted, it became like any other airplane and the stick position commanded the control surface directly
 
Did either pilot attempt to use the sidestick priority button?

The nose guy did it first, and thought he had control, but the other guy pushed it after, so actually had control.

I see this as an issue when you have the sticks not connected, so the two pilots did not realize they were doing different things.
 
Did either pilot attempt to use the sidestick priority button?

Neither pilot used the priority button and the dual inop alerts were lost in the multitude of warnings the A330 can generate.
 
Except that due to the iced up pitot tube, the system reverted to another mode and full command of the surface (like most planes) was based on the stick with command.

Normally, the system commands a performance. But when the system reverted, it became like any other airplane and the stick position commanded the control surface directly

Regardless of mode the system sums stick inputs. In the case of AF447 the aircraft was in alternate 2 which still has pitch authority commanded via G load. Neural stick equals 1 G. Once the aircraft was fully stalked at approximately 45 degrees AOA it was in 1 G flight and the pitch system was quite happy. The summed stick inputs were asking for 1 G. Normally you would have expected the aircraft to have reverted to abnormal attitude law because the AOA exceeded 30 degrees. The aircraft never did this because the system outsmarted itself and rejected all ADC inputs. That law would have provided direct stick input to the elevator and also disabled the auto trim function which ran the trim full nose up.
 
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The report I read stated they were in a law that can direct control of elevator from stick (like a normal airplane), not a command to a G loading.
 
The report I read stated they were in a law that can direct control of elevator from stick (like a normal airplane), not a command to a G loading.

The report you read was wrong. They were in alternate 2. Pitch remains in G mode however roll reverts to direct law. This caused the ab intro first officer to get into a roll PIO. It’s likely he focused on that and failed to maintain a instrument scan and allowed the aircraft to pitch up until the stall. There is very little excess thrust available in the 330 at high altitude. Any nose up excursion will quickly cause a loss of airspeed even with auto throttles engaged. There are numerous reports where A330’s were allowed to get slow in cruise and had to initiate a decent to regain speed. The A330 has a large wing but is relatively underpowered. If you want to know what really happened please read “Understanding AF 447”. It includes actual FDR data.
 
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