AF 447's FDR located

CAPFlyer · **Posted:** Tue May 31, 2011 9:57 pm

jtramo wrote:

AOA has a lot of bearing on pitch and vice versa, and the aoa combined with airspeed controls the PLI (pitch limit indicator showing the pitch that will result in a stall). Pitch up and retard power as this crew did, and pitch/AOA increases to stall. They were deep stalled for 6 minutes! I suppose Im having issues conceptualizing the AOA VS Pitch as they were in straight and level flight and not an AOA driven accelerated stall. In this case critical pitch indications would not be the same as AOA but pitch stall angle would almost mirror AOA (-+chord) isnt that correct?

You didn't read my statement. My statement is that AoA referenced in the report is NOT AVAILABLE to the crew. Additionally, no mention has been made in the report whether the PITCH DATA referenced was being displayed on the PFD or not, only that there was a disagreement in IAS between the PFD and the standby instrument. As such, because they don't state it, then we must not assume that it was working. Conversely, we must not assume it was malfunctioning either. We simply don't have the information. My point for saying this is simple - AoA and pitch are not directly interrelated. You must have airspeed to make AoA occur. You can be at any pitch and have an AoA of 0*. You can be at any speed and have an AoA of 0*. You can't be at any pitch and any speed and still have an AoA of 0*.

Additionally, the A330 flight laws went into the "Alternate Law" (as stated in the report) which removes most of the pitch and roll protections and in some modes removes the autotrim. As such, they are essentially flying a "dumb" airplane in this situation. So, it may be that they assumed there were protections in place that weren't, but again, without all of the information about what the PFDs were or weren't showing, we can't know that for sure.

The Inspector · **Posted:** Tue May 31, 2011 10:15 pm

About a zillion moons ago, didn't a NORTHEAST 727 on a repositioning overnight back into the ground after the AOA's iced over and the crew lost all their pitch and attitude info?

CAPFlyer · **Posted:** Tue May 31, 2011 10:25 pm

I searched the NTSB database and didn't find anything. Also did a cross-check during the majority of 727 operations and didn't find anything. Do you have a general timeline (like maybe even just a decade)?

The Inspector · **Posted:** Wed Jun 01, 2011 8:38 am

No, but thought I remembered reading about it in FLYING Magazine when it still amounted to something, and it was a long time ago.

jtramo · **Joined:** Wed Nov 05, 2008 8:39 pm **Posts:** 359

Basic issue here: Stall was induced by the pilot flying. Stall warning went off. Pitch requested was extreme nose up. Thrust requested was idle or cruise 99% of the several minute long stall. If you are IMC without functioning instruments why would you pitch full up, power back and ignore the stall warning? Who cares about AOA? The pitch was initiated by the pilot. Procedure is maintain attitude and thrust, not start an inside loop.

At the end of the day we may never know, because Airbus is very busy trying to turn an airplane error into a pilot error. From the information presented so far, they did the unthinkable in response......but it was a response to an aircraft failure in IMC, one of the most deadly situations in aviation.

airnutz · **Posted:** Wed Jun 01, 2011 3:52 pm

Ya know, ya read stuff like this and wonder, with all the fancy 'whistles and bells computer stuff', why there isn't some basic analog turn 'n bank, pitch and airspeed indication in order to give the pilots a chance to fly the plane and salvage the situation. Probably just my ignorance showing...

Edit-Altitude indicator would be another.

The Inspector · **Posted:** Wed Jun 01, 2011 6:39 pm

Even though it's been refined and worked on, the basic setups and programming parameters in the FMC's on Airbus aircraft are set up to take carbon based inputs (people) as 'advisory' because the computer knows best, so while you as the guy driving the bus can SEE the approaching flagpole, the computer doesn't and puts you on 'we'll get back with you later' status. It's better than it was years ago when there were so many odd incidents (some fatal) with especially A-320 flight controls and the complete inability for the crew to override the all knowing, all seeing computers (including one incident caught on video from the ground, of a flight crew almost doing aerobatics in the pattern fighting with the FMC programming for control of the aircraft). I believe it took a couple of really near things with LUFTHANSA before the computers were re-programmed.

CAPFlyer · **Posted:** Wed Jun 01, 2011 7:15 pm

Actually, it took Lufthansa finally getting tired of it and hiring their own software programmers and fixing the problem themselves and charging Airbus for the fix.

That didn't go over well with Airbus nor did Lufthansa practically giving away the flight sim software updates that Airbus was playing "hardball" on with United and Frontier. The sim techs at United told me to Airbus changing the software where it could only be installed on a single simulator.

The Inspector · **Posted:** Wed Jun 01, 2011 8:16 pm

I know first hand that unless you get maintenance training from AIRBUS Instructors (@ really steep prices) they donot recognize that your people have ever been trained how to work on their aircraft. And they were pretty snotty about training instructors @ Repair stations, we resorted to using the customers instructors to teach us what they wanted done on their aircraft.

bdk · **Joined:** Sun May 02, 2004 1:16 am **Posts:** 11330

There was an incident many years ago I read on the old Douglas daily report system about an Airbus incident that nearly resulted in disaster, but at best resulted in many unhappy passengers. As I recall, the flight crew initiated a go around without disconnecting the autopilot/autoland system correctly. This caused the autopilot to fight the pilot input using stabilizer trim. When the autopilot finally disconnected, the out of trim condition overpowered the pilot's input, causing the aircraft to pitch up to as I recall, over 80 degrees, not once, but about three times before the pilots were able to bring the aircraft under control.

I may be fuzzy on the details, but this was based upon an FAA report and is not an internet rumor (predates Al Gore inventing the internet anyhow).

muddyboots · **Posted:** Wed Jun 01, 2011 10:02 pm

bdk wrote:

(predates Al Gore inventing the internet anyhow).

boy you are really ate up with it aren't you?

bdk · **Joined:** Sun May 02, 2004 1:16 am **Posts:** 11330

Lost your sense of humor?

The Inspector · **Posted:** Thu Jun 02, 2011 1:35 am

BDK,
That's the incident I mentioned that got captured on video tape-

CAPFlyer · **Posted:** Thu Jun 02, 2011 8:13 am

bdk wrote:

There was an incident many years ago I read on the old Douglas daily report system about an Airbus incident that nearly resulted in disaster, but at best resulted in many unhappy passengers. As I recall, the flight crew initiated a go around without disconnecting the autopilot/autoland system correctly. This caused the autopilot to fight the pilot input using stabilizer trim. When the autopilot finally disconnected, the out of trim condition overpowered the pilot's input, causing the aircraft to pitch up to as I recall, over 80 degrees, not once, but about three times before the pilots were able to bring the aircraft under control.

This is also what is believed to be the source of the Air France flight 296 accident, even though Airbus denies it vigorously (and the official report does to, but then again, the investigation itself is still in doubt).

bdk · **Joined:** Sun May 02, 2004 1:16 am **Posts:** 11330

The Inspector wrote:

BDK,
That's the incident I mentioned that got captured on video tape-

Wow! If you find that on YouTube, please post the link!!!!

Where did that occur and do you remember about when?

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AF 447's FDR located

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