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  • Gabriel
    replied
    Originally posted by Evan View Post
    Can we all agree that the definition of "fat dumb and happy" is "matching and mashing to put the nose back where is was" whilst contending with turbulence and roll in manual flight after a sudden loss of autoflight, the loss of airspeeds and an urgently developing failure cascade?
    At least in the short term, sure.

    How sustainable is 5deg and CLB in the long term starting from 35000ft ISA+20?

    A simple calculation tells me that they would have had an initial climb of 2800 fpm. The speed was going to go down.

    Leave a comment:


  • Evan
    replied
    Originally posted by ATLcrew View Post
    Affirmative. Even if we're in a gentle descent, that's still FDnH.
    Can we all agree that the definition of "fat dumb and happy" is "matching and mashing to put the nose back where is was" whilst contending with turbulence and roll in manual flight after a sudden loss of autoflight, the loss of airspeeds and an urgently developing failure cascade?

    Leave a comment:


  • Evan
    replied
    Originally posted by Gabriel View Post
    Who said anything about maintaining the altitude? Will 5 deg + CLB maintain the altitude?

    Leave the throttle alone, keep the pitch, and you will be fine.
    Or try to keep the altitude if you want. If you do that and you need increasing pitch to keep it, you need to add more thrust. It is written in the UAS PROCEDURE!
    Let me be more specific: Can an A330-200 at this weight/altitude with power set at 83% N1 not descend and still fly well below alpha prot AoA?

    We always lose context with these arguments. So let me remind you of the context:

    Pierre Bonin, PF, was clearly concerned about the weather situation and the altitude prior to the event. He repeatedly asked the captain about RECMAX and indicated that he wanted to climb above the weather. The Captain did not give him an answer before retiring. He continued to mention this with the relief FO who replaced the previous one in the left seat. He wanted to climb. HE DEFINITELY DID NOT WANT TO DESCEND. When the event happened, due to the role of Mach in calculating altitude, the altimeter began to display a negative rate, a descent. He reacted by adding pitch, but overcontrolled, probably due to a lack of experience hand-flying at high altitude where manual inputs are amplified (and he was also contending with on onset of roll at that moment). Add to this his now urgent desire to climb over the storm (RECMAX was about FL380). And now add to that the fact that the N1 is locked at 83%.

    That's the context.

    Now imagine that he didn't continuously pull up into a stall, but rather leveled out, with FDnH pitch, intent on NOT DESCENDING and with a desire to then climb steadily to FL370 (instead of following the memory procedure and CRM/QRH procedure).

    Is that not a bit unsafe? Or should I say, is that not more dangerous than following the procedure?

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by Evan View Post
    But is that your definition of FDnH?
    Affirmative. Even if we're in a gentle descent, that's still FDnH.

    Leave a comment:


  • Evan
    replied
    Originally posted by ATLcrew View Post
    I don't know (I'm thinking it should), but if not, you match and mash and put the nose back where it was. It's not hard, really.
    But is that your definition of FDnH?

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by Evan View Post
    Q: The N1 was previously at 100% Pitch was at 0 (1.8 was the FDnH value 10 secs earlier, before the selected guidance). Can an A330-200 at this weight/altitude maintain 35,000 ft with power set at 83% N1 and still fly well below alpha prot AoA?
    I don't know (I'm thinking it should), but if not, you match and mash and put the nose back where it was. It's not hard, really.

    Leave a comment:


  • Gabriel
    replied
    Originally posted by Evan View Post
    Q: The N1 was previously at 100% Pitch was at 0 (1.8 was the FDnH value 10 secs earlier, before the selected guidance). Can an A330-200 at this weight/altitude maintain 35,000 ft with power set at 83% N1 and still fly well below alpha prot AoA?
    Who said anything about maintaining the altitude? Will 5 deg + CLB maintain the altitude?

    Leave the throttle alone, keep the pitch, and you will be fine.
    Or try to keep the altitude if you want. If you do that and you need increasing pitch to keep it, you need to add more thrust. It is written in the UAS PROCEDURE!

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by Evan View Post
    Does the sudden loss of autoflight and reversion to alternate law impact the safe conduct of the flight?
    Negative.

    Leave a comment:


  • Evan
    replied
    Originally posted by ATLcrew View Post
    Affirmative.
    Q: The N1 was previously at 100% Pitch was at 0 (1.8 was the FDnH value 10 secs earlier, before the selected guidance). Can an A330-200 at this weight/altitude maintain 35,000 ft with power set at 83% N1 and still fly well below alpha prot AoA?
    Q: Does the sudden loss of autoflight and reversion to alternate law impact the safe conduct of the flight?

    Leave a comment:


  • Gabriel
    replied
    Originally posted by ATLcrew View Post
    The document Gabriel linked is actually from 2006 (before AF447) which is why the memory item there reads differently than it does now. Now it OPENS with "If safety of flight is impacted".
    Actually, yes, the document is from 2006 and AF was in 2009, but this document IS the change when they added the "I the safe conduct of the flight is impacted ==> [memory items]".

    You have the old version (where you had in instruction that told you when to apply the ADR check procedure and when the UAS procedure that lacked the "If..." sentence) and the new UAS+ADR unified procedure with the "If..." sentence (in page 17).

    Leave a comment:


  • 3WE
    replied
    Originally posted by Evan View Post
    Q: Is 0-3 pitch (known values) and 83% N1 at their current weight and altitude FDnH?
    I don't have a phugoid clue.

    But based on rather limited 172 time, I would guess yes because ~80% power and relatively level attitude tend to be robust pitch and power levels.

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by Evan View Post
    Q: Is 0-3 pitch (known values) and 83% N1 at their current weight and altitude FDnH?
    Affirmative.

    Leave a comment:


  • Gabriel
    replied
    Originally posted by Evan View Post
    Q: Is 0-3 pitch (known values) and 83% N1 at their current weight and altitude FDnH?
    A: Yes.

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by 3WE View Post
    That deserves a post all it's own.

    And he interjects his wisdom to us AND feeds homeless kittens.

    I only hope we provide some entertainment as he pops popcorn.
    A post? Hell, I'm going to print it out, frame it, and hang it on my glory wall.

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by Evan View Post
    Bottom line (hasn't changed): If the crew of AF447 (and every other instance of high-altitude UAS) had applied the standard memory item pitch and power values, nothing bad would have happened, whereas when left to individual pilot improvisation, anything can happen. Why do pilots (and apparently now, the industry itself) continue to resist that hard lesson and that self-evident truth?
    Because that's the bottom line only in your mind. The memory item was not applicable in this case. You disagree, and that's fine, that's your business. The document Gabriel linked is actually from 2006 (before AF447) which is why the memory item there reads differently than it does now. Now it OPENS with "If safety of flight is impacted". Why? Because Airbus wants us to initially do NOTHING. Not improvise, not do memory items, nothing. Just breathe. Keep breathing. Call for ECAM actions. Keep breathing. If the thrust is not where you want it, match and mash. If you got no IAS, but everything else jives, keep breathing.

    I'm not paid to regurgitate memory items, I'm paid to know my airplane, which includes when NOT to use memory items. Why do you continue to resist that self-evident truth?

    Leave a comment:

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