The date is set.

[3WE]

You (Evan) can't disconnect the concepts of lowering the nose from reducing AoA.

I know you guys ignore me because of my crap stirring; however, I placed a very short and simple reply above.

I some sense, Evan is right...you are going to change attitude if you are going to change AOA. They are basically directly linked...if you want to change one, you will almost always need to adjust the other.

Even though they are technically completely independent.

Evan and I actually think a little bit alike...I am going to lower my ATTITUDE a stall warning occurs...

I also have my Gabe side...a plane can stall at ANY attitude...so I will KEEP lowering it if the stall warning keeps occurring [and try to exercise common sense, If I'm in a 90-degree dive and the wind noise is intense, maybe the stall warning is wrong]...because it's really the AOA I have to fix...and they are technically independent.

I recognize the sad truth that Air France was at a nice healthy attitude and power setting for much of its descent...those are generally good things to have.

[Gabriel]

[Educated Guess] Gabriel knew what was happening (stickshaker/excessive AoA/impending stall) but not why it was happening. As far as he knew, he was flying at his target airspeed, so watching airspeed isn't much help in this case. What he did know was how to use the yoke to silence the stickshaker while preserving precious altitude, and that power was on so time would equate to increased airspeed. It would not surprise me to learn that this task was the sole focus of his attention until the stall warning ceased. This is what investigators call 'tunneling". In some situations. such as this one, it is necessary.[/Educated Guess]

Yes!!!

[Gabriel]

Thank you! I think we can agree that 'lowering the nose' and 'reducing pitch' are the same thing?

Yes, lowering the nose and reducing pitch is the same thing, but it is not the same thing that reducing AoA.

I swear sometimes I think you're playing with my head. Like when you say:

Wrong, I didn't achieve the AoA reduction by reducing pitch.

Yes, you did! Initially. Which is the correct thing to do!

Except that the stickshaler happened AFTER "The first time I relieved back pressure was yes with the intent of lowering the nose, reduce the climb rate, and gain speed".

Look, I get everything you are saying about AoA and what you needed to do with approach-to-stall in close ground proximity.

I don't think you do.

Don't stall. Don't sink (much). Power out of it. But the first action after stickshaker, if you have any altitude to give, is to relieve some back pressure with the intention of slightly lowering the nose**. I think you demonstrated this PERFECTLY.

See? I told you didn't. You (Evan) can't disconnect the concepts of lowering the nose from reducing AoA.

I think this is another of our trademark Semantic-Eristic Arguments® But aside from that I do find this all very interesting and educational.

If that's the case, you should think fixing your semantics. Becaause AoA and pitch are two related but different animals (the difference between them is called climb gradient, by the way: if the pitch increases but the climb gradient increases even more (perfectly possible in a speed-gaining situation), then the AoA WILL go down even if the pitch goes up).

**And even if you don't have any altitude to give, it is better than stalling. Remember our discussion about the A320 that crashed in the 1988 Habsheim Air Show? The pilots wanted to blame the aircraft for not letting them preserve altitude but doing so would have resulted in an unsurvivable crash. By prioritizing stall avoidance over ground avoidance, the plane saved over a hundred lives.

I agree, in this sense. You need to reduce AoA at least barely as needed to silence the stickshaker. If ground/obstacle clearance is of concern, this at least becomes at most too. That leads to the the modulation around the stickshaker AoA (for non-airbus-in-normal-law airplanes). In that condition, thrust, energy, becomes paramount too, since you need potential energy (i.e. altitude) and you need to get it from somewhere and very likely it will not come from trading speed at that point (that is the part where I disagree with the current industry standard). If that, even when made perfectly, results in the nose going down and in loss of altitude, let it be. You are not going to preserve altitude by stalling anyway.

[3WE]

BTW: Instant recall procedures are there for a very specfic reason: to buy time, to allow the pilots to regain and maintain stable flight until their situational awareness can catch up and their rational mind can take over.

Who said that a measured nose-down input and immediate glace at attitude airspeed (and AOA indicator if you are Gabe) is not an instant-recall procedure for a 152 or a 747 when there is a stall warning?

The intent is very specific even though the aircraft type is not.

Edit: Yes, it's interesting to consider that Gabe's airspeed was "correct"...still, it's one of the first few things you'd need to check as you deal with the unexpected stick shaker...It's all beautifully simple...Ok, I'm still climbing...and I do (do not?) have a critical climb angle concern, so maybe I can fly a little fast for a moment while my engineer rechecks the target airspeed.

[Evan]

.

1. 30 seconds of each recurrent training devoted to the statement: "It's important to watch your airspeed and you might want to lower the nose to address stick shakers and stalls

And what would that have to do with this thread?

[Educated Guess] Gabriel knew what was happening (stickshaker/excessive AoA/impending stall) but not why it was happening. As far as he knew, he was flying at his target airspeed, so watching airspeed isn't much help in this case. What he did know was how to use the yoke to silence the stickshaker while preserving precious altitude, and that power was on so time would equate to increased airspeed. It would not surprise me to learn that this task was the sole focus of his attention until the stall warning ceased. This is what investigators call 'tunneling". In some situations. such as this one, it is necessary.[/Educated Guess]

BTW: Instant recall procedures are there for a very specfic reason: to buy time, to allow the pilots to regain and maintain stable flight until their situational awareness can catch up and their rational mind can take over.

[Evan]

The first time I relieved back pressure was yes with the intent of lowering the nose, reduce the climb rate, and gain speed.

Thank you! I think we can agree that 'lowering the nose' and 'reducing pitch' are the same thing? I swear sometimes I think you're playing with my head. Like when you say:

Wrong, I didn't achieve the AoA reduction by reducing pitch.

Yes, you did! Initially. Which is the correct thing to do!

Look, I get everything you are saying about AoA and what you needed to do with approach-to-stall in close ground proximity. Don't stall. Don't sink (much). Power out of it. But the first action after stickshaker, if you have any altitude to give, is to relieve some back pressure with the intention of slightly lowering the nose**. I think you demonstrated this PERFECTLY. I never said anything about "you need to shove the nose down", not only because this might put you six feet underground but because this might cause the somatogravic illusion that you are pitching up. I wouldn't advocate any shoving. I would advocate skillfully managing.

I think this is another of our trademark Semantic-Eristic Arguments® But aside from that I do find this all very interesting and educational.

**And even if you don't have any altitude to give, it is better than stalling. Remember our discussion about the A320 that crashed in the 1988 Habsheim Air Show? The pilots wanted to blame the aircraft for not letting them preserve altitude but doing so would have resulted in an unsurvivable crash. By prioritizing stall avoidance over ground avoidance, the plane saved over a hundred lives.

[3WE]

Blah blah blah blah times a very large number

.

Why does Bobby state that he's glad he's out of the business?

[not_blue font]Evan want's pilots to have Gabriel's knowledge along with Evan's list of knowledge[/eye rolling]

Sorry guys, isn't the answer much simpler?

3BS proposes:

1. 30 seconds of each recurrent training devoted to the statement: "It's important to watch your airspeed and you might want to lower the nose to address stick shakers and stalls, because we have had those amazingly sad stall-crashes and a plane can theoretically be stalled at any airspeed and attitude."

OK, maybe that's a tad condescending, but there have been those crashes and that's the whole point- a quick reminder.

2. Do an actual (OK, simulated) stall once a year. (Us outsider experts have ZERO idea what it really feels like and it can be VERY gentle since the plane is very heavy)

The rest of the recurrent training can focus on acronyms and type-specific checklists as determined by very smart insider trainers.

[Gabriel]

1) Because I'm trying to keep the discussion to the event you experienced. As I understand it (correct me if I'm wrong), an incorrect TOW was entered, thus the lift-off speed was too low

Correct

the plane could lift off but not effectively climb at that airspeed

Actually the plane was climbing, but the speed had settled well below V2, and now we know it was a wrongly slow V2, so we were much slower than the correct V2 for the weight.[/quote]

without approaching critical angle (stickshaker) and thus the solution was to fly around the stickshaker (maximum allowable PITCH and thus maximum allowable AoA for that speed) while allowing thrust to build up sufficient airspeed to climb at a safer margin below critical angle (no stickshaker).

No. The plane was climbing, the speed had settled too slow, and I had no idea if we were close to the stickshaker AoA.
The first time I relieved back pressure was yes with the intent of lowering the nose, reduce the climb rate, and gain speed.
It worked and the plane started to gain speed, but the problem was that, while the nose was still quite high, apparently the reduction in pitch had been a bit too much, as evidenced by the fact that the plane was now sinking.
That is the point where I pull back with both hands, manage to arrest the descent but also to activate the stickshaker. This was the first clear evidence of about where the AoA was. Up to that point, there had been no intention to keep the AoA in any specific sweet spot or anything.
I relieve a bit of back pressure, this time to reduce AoA a bit (and I didn't care about pitch in that moment) and the stickshaker stopped. The activation was brief. One second maybe? Surely less than 2. What do you say BB? BB says that the pitch did go down, but that was neither the intent nor the means to reduce AoA. In very similar circumstances the pitch up combined with an even larger increase in climb gradient, both due to the increase of speed, may have been greater than my slight reduction in AoA which would have been a case of AoA reduction with simultaneous pitch increase. In either case, what happened or may have happened withe the pitch was or would have been a by-product, a side effect, not an intent or a means. And, very likely, the stickshaker would have stopped by itself a bit later if I had kept the yoke where it was instead of letting it forward a bit. Why? The speed was increasing, the pitch rate was increasing, the climb gradient was increasing even faster, and that means that the AoA would have been reducing. So why the stickshaker in the first place? It was probably a temporary overshoot of the equilibrium AoA due to the rotational inertia. And that corrects by itself (short-period mode of oscillation, similar to a weather-vane). But I didn't sit there and wait. Now, realize that if pitch rate was contributing to stop the stickshaker (in either example), then the pilot needs to move the elevator forward sooner or later, because with a fixed elevator and pitching up, the plane will start reducing the pitch rate at some point, and there the AoA will increase again and the stickshaker will activate again.

In my case, I pulled back up again with the intention to look for that sweet spot, the onset of the stickshaker, but I never found it. The plane climbed out without activating the stickshaker again and I stabilized at about 15 deg of pitch, which required relieving back pressure again to avoid overshooting that goal.

2) I have a basic, fundamental understanding of phugoid. Not enough for the advanced theoretical fringes of this conversation apparently...

Well, let's say that while the first-order approximation for that mode of motion is assuming that the angle of attack remains constant, it is not. It may vary between a little bit to quite a bit depending on the amplitude of the oscillation. And while the 1st order approximation gives fairly approximated results (in terms of period or frequency and time-to-half the amplitude), it doesn't explain why it happens other than saying that it is an exchange between potential and kinetic energy. In reality, there is an average AoA (which is the AoA the plane would have if it was flying straight and level with the elevator in the same fixed position and the speed wherever needs to be to fly straight and level, that is trim speed), and the AoA oscillates around that value, reducing when the plane pitches up and increasing when the plane pitches down (and said increase or reduction is proportional not to pitch but to pitch rate). So a nice way to find approximately your trim speed when in a phugoid is to mark the speed when the pitch trend reverses, i.e when it stops increasing and starts reducing or vice-versa. At that point the AoA is the AoA of equilibrium and the speed would be very close to your trim speed. Now you can use throttles to work around that speed. 10 knots below will give you a certain nose-down pitch rate. 5 knots below another. The opposite will happen with speed above trim speed. Trim speed will kill the pitch rate. You can use that to initiate climbs and descents and establish in stable, non oscillatory trajectories, be or climbing, descending, or level. All without touching the elevator. (note: that is in a perfect world without thrust-pitch coupling).

[Evan]

I can explain a bit more if you want, but let me ask you 2 questions first:
1- Why are you NOT asking about this? "you can reduce AoA and increase pitch, climb rate and climb gradient at the same time." If you understood that, you would probably not be asking if I was joking or about this other question. That is what is called power out of the stall, or something similar, and in certain circumstances can be enough, at least in the short term, to get out of a stall or approach to stall (that is REDUCE THE AoA) without moving the yoke forward. It is what the old approach to stall recovery procedures of the type "TOGA and pitch 10 ANU" were based on (because, yes, they were based on fundamentals). It is also the reason (or one of them) why I am not happy with the new universalized procedure that calls to not add thrust until not recovering from the stall first.
2- How well do you understand the phugoid (i.e. the long-period mode of oscillatory longitudinal motion)? Because that explains both statements (that you can reduce AoA and increase pitch at the same time and that with a fixed elevator pitching up reduces AoA). And can also help you land a DC-10 after a total hydraulic failure.

1) Because I'm trying to keep the discussion to the event you experienced. As I understand it (correct me if I'm wrong), an incorrect TOW was entered, thus the lift-off speed was too low (and/or configuration?), the plane could lift off but not effectively climb at that airspeed without approaching critical angle (stickshaker) and thus the solution was to fly around the stickshaker (maximum allowable PITCH and thus maximum allowable AoA for that speed) while allowing thrust to build up sufficient airspeed to climb at a safer margin below critical angle (no stickshaker).

So momentary reduction and then occillation of PITCH whilst powering out of the stall regime, and perhaps climbing the entire time. That's my take. If that is accurate, then yes, over a period of time you are increasing pitch, climb rate and climb gradient at the same time. But not before first arresting the pitch, climb rate and climb gradient with a reduced PITCH command to silence stickshaker in the first place.

Or did you merely maintain the stickshaker onset pitch command, neither increasing nor decreasing it, and simply allow power to silence the stickshaker before adding a bit more? I guess that is what I'm asking you to clarify...

2) I have a basic, fundamental understanding of phugoid. Not enough for the advanced theoretical fringes of this conversation apparently...

[Gabriel]

I agree with you. We really SHOULD require pilots to have much of the knowledge you possess, but I'm not sure how practical that is, especially with a pilot shortage. You do realize that the 'brand' that 3WE has given me here—that I am satisfied if pilots only show proficiency on procedures and not on fundamentals—is either a figment of his imagination or just a device his own amusement? I want pilots to know EVERYTHING they possibly can.

I propose that it doesn't take much (if any) more resources. It does take a different approach on what we teach and train and how we teach and train.

Yes! the means! Of course the goal is to reduce AoA, but I'm talking about the means. Yes, there are means to lower AoA without lowering pitch, I never said otherwise, but in this case, by relieving back pressure, you are commanding the elevators to reduce the pitch attitude. Am I wrong or are you just playing with me now?

You are wrong and I am not playing with you. I am commanding the elevators to reduce the angle of attack, which in certain circumstances (very similar to the one I was) can be achieved while increasing pitch at the same time.

But explain this a bit more if you could:

Did you know that, for a fixed elevator/stabilizer position, the plane pitching up REDUCES the angle of attack?

Easy: Because the angular speed of the pitch-up motion (i.e. the pitch rate) induces a vertical component of the local airspeed in the stabilizer that increases the AoA (or reduces the negative AoA) and hence increases the upward lift (or reduces the downward lift) hence reducing the whole-airplane AoA. In more for-dummy and inexact but easier words: the tail moves down and the air pushes it up. It is what provides dampening to the pitching motion, a delta of lift on the tail that opposes pitch rate.

I can explain a bit more if you want, but let me ask you 2 questions first:
1- Why are you NOT asking about this? "you can reduce AoA and increase pitch, climb rate and climb gradient at the same time." If you understood that, you would probably not be asking if I was joking or about this other question. That is what is called power out of the stall, or something similar, and in certain circumstances can be enough, at least in the short term, to get out of a stall or approach to stall (that is REDUCE THE AoA) without moving the yoke forward. It is what the old approach to stall recovery procedures of the type "TOGA and pitch 10 ANU" were based on (because, yes, they were based on fundamentals). It is also the reason (or one of them) why I am not happy with the new universalized procedure that calls to not add thrust until not recovering from the stall first.
2- How well do you understand the phugoid (i.e. the long-period mode of oscillatory longitudinal motion)? Because that explains both statements (that you can reduce AoA and increase pitch at the same time and that with a fixed elevator pitching up reduces AoA). And can also help you land a DC-10 after a total hydraulic failure.

[BoeingBobby]

I am glad that I did it when I did. It just isn't fun anymore.

[Evan]

Of course, automated planes are basically procedure followers that are not pilots. Doesn't sound too wonderful to me.

I disagree with that. Automated planes also fly the plane by being 'in a conversation with the plane'. FBW uses a constant feedback loop that mimics human proprioception. Remember, most modern airliners are providing artificial feel to the human pilots, allowing them to be 'in a conversation with the plane', and that feel is derived from the same sort of sensors and internal reference devices that are used on autonomous drones. In certain situations, these devices are more reliable and less prone to error than the human sensory organs. Of course, humans have the benefit of vision and an adaptable power of reason. I don't think I would trust an automonous passenger aircraft in this lifetime, but I expect future technologies will include visual recognition and some pretty impressive ai.

[Evan]

Evan, you quoted several bunches of my post, but forgot this part:

"you can reduce AoA and increase pitch, climb rate and climb gradient at the same time."

You said "Yes, which, in this case was achieved by... reducing pitch, right?"

Wrong, I didn't achieve the AoA reduction by reducing picth. I achieve AoA reduction by, well, reducing AoA which in turn was achieved by relieving a bit of back pressure on the yoke. The reduction of pitch was a side effect, but not the goal, the means....

Yes! the means! Of course the goal is to reduce AoA, but I'm talking about the means. Yes, there are means to lower AoA without lowering pitch, I never said otherwise, but in this case, by relieving back pressure, you are commanding the elevators to reduce the pitch attitude. Am I wrong or are you just playing with me now?

Did you know that, for a fixed elevator/stabilizer position, the plane pitching up REDUCES the angle of attack? This is something that most pilots don't know even when, if you think of it a bit, it's quite obvious. And they should. Should they know this because it is a necessary knowledge for everyday flying, or for a specific emergency maneuver? No, they should know it because it is part of the GENERAL knowledge of how planes fly, and knowing how planes fly makes you a better pilot. Why don't they know that? Because they are stupid? Because they don't like to study? No, it is because WE DON'T TEACH THEM that.

I agree with you. We really SHOULD require pilots to have much of the knowledge you possess, but I'm not sure how practical that is, especially with a pilot shortage. You do realize that the 'brand' that 3WE has given me here—that I am satisfied if pilots only show proficiency on procedures and not on fundamentals—is either a figment of his imagination or just a device his own amusement? I want pilots to know EVERYTHING they possibly can.

But explain this a bit more if you could:

Did you know that, for a fixed elevator/stabilizer position, the plane pitching up REDUCES the angle of attack?

[Gabriel]

Of course, automated planes are basically procedure followers that are not pilots. Doesn't sound too wonderful to me.

The thing is now planes are highly automated but they still REQUIRE pilots to be safe. When the automation reaches the point where pilots are not longer needed to be safe, it will be not such a problem not to have pilots and have just automated procedure followers. At that point, the automation will need to react correctly to an UAS event or to a saltshaker (including judging from other variables whether is it fair or false). There will still be errors and bugs and lives will still be lost, but there will be almost no repetition of the same errors since a fix will be a hard fix-one-fix-all solution. And aviation will have reached its top of safety and boredom.

[Gabriel]

Evan, you quoted several bunches of my post, but forgot this part:

"you can reduce AoA and increase pitch, climb rate and climb gradient at the same time."

You said "Yes, which, in this case was achieved by... reducing pitch, right?"

Wrong, I didn't achieve the AoA reduction by reducing picth. I achieve AoA reduction by, well, reducing AoA which in turn was achieved by relieving a bit of back pressure on the yoke. The reduction of pitch was a side effect, but not the goal, the means, or even a necessary effect of every AoA reduction. I didn't know if I was reducing pitch or not, I only know now by BB's recount.

Most airplanes (this 747-200 sim included) have only a binary AoA indicator. The 2 states are "AoA safe" and "AoA close, at or beyond stall". There is no direct way to know where you are within each state. So when you say "flying in that sweet spot just below critical angle", how do you know? I don't know that. I was looking for that sweet spot which is the stickshaker onset AoA, but the plane started to climb with the stickshaker still silent so I stopped looking for that sweet spot. The plane was, at that point, accelerating quickly, and probably the AoA was reducing quickly too. Did you know that, for a fixed elevator/stabilizer position, the plane pitching up REDUCES the angle of attack? This is something that most pilots don't know even when, if you think of it a bit, it's quite obvious. And they should. Should they know this because it is a necessary knowledge for everyday flying, or for a specific emergency maneuver? No, they should know it because it is part of the GENERAL knowledge of how planes fly, and knowing how planes fly makes you a better pilot. Why don't they know that? Because they are stupid? Because they don't like to study? No, it is because WE DON'T TEACH THEM that.

I think we are not doing a good job at training pilots in fundamentals, from the most basic training. I had experienced pilots, even instructors, even aeronautical engineers, and even books on how planes fly, tell me wrong basic things. Things that range from the dangers of downwind turn to how the fulcrum effect make high wing airplanes more stable than low wing ones, among a long list of wrong things. Maybe that wrong basic thing is not important as long as you make the right control inputs to enforce the required performance and flight path within the limits of what the plane can actually do given the limitation of the laws of Physics. But what I find when I fly the plane is like I am in a conversation with the plane. The plane speaks to me through its (change in) performance, attitude, noises, control feedback, etc. And I talk to the plane through control inputs. I talk and the plane responds, the plane talks and I respond. And we understand each other. This conversation can lead to misunderstandings or a total breakdown of the communication of you don't understand the airplane's language well.

I am a pilot, I have something like 180 hours + a few dozen hours in flight training devices. Many, maybe half, of these hours were with an instructor in the right seat. I went through ground school, passed my 2 written, oral and check rides. And most what I know of how planes fly DIDN'T COME FROM THERE. Part came from there, part came from the university, part came from own research, part came from self reflection and study, part came from trying things out in the airplane without an instructor (don't worry, safe things only). That is, most of it came from things pilots are NOT exposed to.

Final word. You said: " 'how do we build this into pilots? We teach them the fundamentals since hour zero...' We do this. Renslow was a certified flight instructor."

Right. Read the part where I said "I had experienced pilots, even instructors, even aeronautical engineers, and even books on how planes fly, tell me wrong basic things." Then read my signature. And the realize why I always say that I am never convinced by imposition of credentials.