Configuration Warnings

[GeeBee]

3 hours ago, Blue on Top said:

1. Yes, we should warn the pilot before the aircraft stalls.  No, I do not want to prevent the airplane from stalling … unless it has really, really bad stall characteristics.  Each airplane is different, and there pros/cons/exceptions on every rule and train of thought.

2. And this is exactly what AF447 flight crew did.  The problem was they didn't train well enough to know that the airplane was not in "normal" mode.  They applied flight controls for the airplane being in "normal" mode (full power, full aft stick for stall recovery), which the airplane was not in "normal" mode.  On a sad note, the airplane gave them exactly what they asked for … full up elevator.  Several good books, at least one TV show (with the NTSB) and the transcripts/flight and voice recorder data are publicly available.

3.  On the Max, Boeing made several big mistakes.  Too complicated to get into here,  Bottom line for me is that those accidents had multiple links in the accident chain.  If any link would have been broken, the accidents would not have happened.  Everyone is now pointing at everyone else saying, "If you would have performed perfectly, you could have prevented this."  That goes for everyone involved: Boeing, FAA, flight crews, maintenance crews, etc.

On a serious note, the more we automate airplanes, the less involved and trained pilots will become.  The "autonomous/autopilots" can no longer give the airplane back to the pilot when something fails because the pilot is the weakest link in those airplanes.  I want to involve the pilot more.

We don't want to prevent the airplane from stalling? The other night I watched a demonstration, where the presenter kept throwing a glass of water on a subject on stage. The subject had a towel and an umbrella. The first time he used the towel. The second time he put up the umbrella. You obviously prefer the towel? Why?

Your characterization of AF447 is totally inaccurate and since you are referencing book, let me be specific. My good friend and colleague, Captain Bill Palmer wrote the definitive work, "Understanding Air France 447". In fact I played guinea pig for him in the sim for his research.

More automation does not mean less training. That is  flawed thinking. It means training in how to manage the automation modality including complete failure.

 

 

[carusoam]

Have we come to the conclusion that the two Max(s) were operated by crews with not enough specific training? Low time pilots, non-US companies...

There has been so much detail given the core of the story got lost...

The news cycle moved on... it all Coronavirus now...

Best regards,

-a-

[Ibra]

11 hours ago, Blue on Top said:

On a serious note, the more we automate airplanes, the less involved and trained pilots will become

Unless you train them for "degraded flying mode" it is hard for them to know that an aircraft is stalled, especially when they get too many conflicted signals on configuration (e.g. trim, flaps, power, stick, spoilers...) and/or performance (e.g. speed, vsi, hdg...)

This is highly relevant for today training as the slightest instrumentation/configuration failure will generally result in a loss of control or upsets due to pilot error rather than aircraft physics, I am not sure if many airlines pilots still beleive they can fly with zero thrust on 2/4 engines and no instrumentation?

The good news we still have cases where crew were still able to "safely fly" on all engines shutdown and even on failed hydraulics/fly-by-wire/instrumentation, but usually those flying profiles were not the typical "all my flying life was in the ATP school"...

Like asking in GA, if one can fly engine off in IMC with limited instrumentation and no auto-pilot ?

 

Edited February 26, 2020 by Ibra

[bradp]

On 2/24/2020 at 6:07 PM, Yetti said:

I asked how many loose gas caps the service writter saw per week.  He said about 1 per week.    I asked why they had not put a warning to say.   Hey dummy tighten your gas cap.    No good response.

They designed that out of my Honda - no more gas cap just a seal on the gas door. 

[bradp]

1 hour ago, Ibra said:

Unless you train them for "degraded flying mode" it is hard for them to know that an aircraft is stalled, especially when they get too many conflicted signals on configuration (e.g. trim, flaps, power, stick, spoilers...) and/or performance (e.g. speed, vsi, hdg...)

This is highly relevant for today training as the slightest instrumentation/configuration failure will generally result in a loss of control or upsets due to pilot error rather than aircraft physics, I am not sure if many airlines pilots still beleive they can fly with zero thrust on 2/4 engines and no instrumentation?

The good news we still have cases where crew were still able to "safely fly" on all engines shutdown and even on failed hydraulics/fly-by-wire/instrumentation, but usually those flying profiles were not the typical "all my flying life was in the ATP school"...

Like asking in GA, if one can fly engine off in IMC with limited instrumentation and no auto-pilot ?

 

What ever happened to basics like unloading a wing, pitch plus power equals performance, and going to “green” data?

Isn’t the best approach when technology confuses to revert to the most simple, reliable instrument / information source (ie if two ADHARs are in disagreement should not the electric gyro driven AI be the most reliable source of information. 

I see an analogous problem with monitoring in the medical field a lot. Say the patient isn’t breathing well, the pulse ox is low and the someone doesn't want to believe it - so people start focusing on the equipment rather than “flying the plane”, trying to fix equipment, replace equipment, try equipment on in another place on the body - meanwhile patient not adequately ventilated etc while people are technology fixated.   In this situation just be looking at the patient - reverting to simple data - chest rise, coloration (blue or not), pulses / perfusion.  It’s a fixation problem that can be addressed with training . 

 

[GeeBee]

Put 100 pilots in a single engine airplane and fail the engine below 500'. What will 95 of them do?

Pull up on the pitch control.

Put 100 VFR only pilots in an airplane, and suddenly plunge it into IMC what will 90 of those pilots do?

Pull up on the pitch control

Put 100 multi engine pilots in a light twin and fail an engine below 500' what will 90 of them do?

Pull up on the pitch control.

[Yetti]

1 hour ago, GeeBee said:

Put 100 pilots in a single engine airplane and fail the engine below 500'. What will 95 of them do?

Pull up on the pitch control.

Put 100 VFR only pilots in an airplane, and suddenly plunge it into IMC what will 90 of those pilots do?

Pull up on the pitch control

Put 100 multi engine pilots in a light twin and fail an engine below 500' what will 90 of them do?

Pull up on the pitch control.

Because that is what everyone is trained to do.  When you hear the stall buzzer pull up just a little more to get to a full stall.  muscle memory.

[GeeBee]

Really? When you lose an engine in a multi engine airplane you are trained to pull up?

When you loose an engine on a single you were trained to pull up? Really?

[Hank]

Just now, GeeBee said:

Really? When you loose an engine in a multi engine airplane you are trained to pull up?

When you loose an engine on a single you were trained to pull up? Really?

Isn't that how we all learned to "practice stalls" as student pilots? Slow down, nose up, stall horn; more nose up, buffet then stall; then recover. Did I miss something?

My goal in my Mooney is to only hear the stall horn just before my wheels touch the ground, but it still chirps intermittently on climbout in gusty conditions.

[GeeBee]

Why would you go to a stall regime when you just lost an engine? Should you instead go to “lost engine regime”?

[Hank]

9 minutes ago, GeeBee said:

Why would you go to a stall regime when you just lost an engine? Should you instead go to “lost engine regime”?

I think the point was that when the plane inadvertently approaches a stall [engine running or not], Primacy of Training takes over and the pilot goes for the full stall instead of initiating recovery. Maybe that is why the FAA changed the PPL curriculum to not stall and not fly at MCA with the horn buzzing? So that we don't learn that such behavior is good?

Edited February 26, 2020 by Hank

[Ibra]

2 hours ago, bradp said:

What ever happened to basics like unloading a wing, pitch plus power equals performance, and going to “green” data?

....It’s a fixation problem that can be addressed with training

Lot of it has to do with trying to achieve a lot of precision using real-time decision while tracking lot of random signals I think taking deep breath (not in your medical sense ) does help with basics: yes, unload wings (& cut power) does work every time, it should simply get any aircraft from any configuration down at "trim speed" with minimal pilot inputs, so nothing much to guess there  this goes for other stuff  as well: fly constant heading bug for 3min instead of looking every 2sec to a GPS moving map, flying a stable 90kts/450fpm works better than actively chasing GS bellow 600ft....

25 minutes ago, GeeBee said:

Really? When you loose an engine in a multi engine airplane you are trained to pull up?

Isn't that what training to make circuit on one engine = pull on stick is about?

I just know someone who had one in an Aztec at 800ft with excess of speed but decided to land in the nearby field instead of trying to make a full circuit, I think he could not maintain height & speed for some reasons, so he decided to stop pulling, he now has strong opinions on flying twins with one engine bellow 2000ft (don't die trying )

 

Edited February 26, 2020 by Ibra

[Yetti]

32 minutes ago, GeeBee said:

Really? When you lose an engine in a multi engine airplane you are trained to pull up?

When you loose an engine on a single you were trained to pull up? Really?

In the Mooney, the stall warning is going to go off really quick.   Once you hear the sound people have been conditioned to pull up.    I have a mental mantra of beep push down beep push down No fan noise push down push down.  

[bradp]

Also my mantra yetti - if I’m flying with an instructor and we’re doing stalls we brief that at the first indication of a stall we’re going to initiate a recovery maneuver (whether the wing is stalled or not). 
 

When I’m flying myself I’ll occasionally take the mooney to a full stall.  When I’m flying with an instructor, I won’t.  This is consistent with the new FAA training material.  First indication do something to correct it. 

[Yetti]

Automation.   Coming off automation.  If I think the car is in control, then I don't brake for the car in front of me.    But it will warn me that I am going to hit it.   Funny thing is when the car is warning it is going to hit something, but it is in control of braking.

[GeeBee]

Might want to take a look at this from an instructor I know. I would note he talks about a friend of his killed at KFFC in a stall spin after engine failure. Now he was not only well trained, he was a CFI-I

 

 

[Blue on Top]

21 hours ago, GeeBee said:

1. We don't want to prevent the airplane from stalling? The other night I watched a demonstration, where the presenter kept throwing a glass of water on a subject on stage. The subject had a towel and an umbrella. The first time he used the towel. The second time he put up the umbrella. You obviously prefer the towel? Why?

2. Your characterization of AF447 is totally inaccurate and since you are referencing book, let me be specific. My good friend and colleague, Captain Bill Palmer wrote the definitive work, "Understanding Air France 447". In fact I played guinea pig for him in the sim for his research.

3. More automation does not mean less training. That is  flawed thinking. It means training in how to manage the automation modality including complete failure.

1.  In 3 words, more available performance.  As I mentioned previously, each airplane is different and each design has different reasons for different systems.  For an airliner that only flies out of few, paved, runways that are much longer than is required, sure, don't let them stall …. but then the pilots won't … better not go there.  You may remember an accident at the Paris Airshow with an A320 that those pilots might disagree with you.  Again, full automation is coming.  Pilots rely on systems to fly the airplane way to much the way it is now.

2. I ordered the book.  I've read the actual transcripts and reviewed the actual cockpit data.  I'm looking forward to reading your friend's book.

3. The training should not be on how to turn the autopilot on and use the FMS.  It should be on what happens when the automation fails and why the automation failed.  Had AF447 crew known that AOA and airspeed are totally independent, would they have still ignored the stick shakers?  They knew some things as they turned the pitot heaters on during the descent.

Bottom line:  I'm looking forward to reading the book.   AND finding a solution(s) that doesn't allow accidents like this.

[Blue on Top]

12 hours ago, GeeBee said:

Put 100 pilots in a single engine airplane and fail the engine below 500'. What will 95 of them do?

Pull up on the pitch control.

Put 100 VFR only pilots in an airplane, and suddenly plunge it into IMC what will 90 of those pilots do?

Pull up on the pitch control

Put 100 multi engine pilots in a light twin and fail an engine below 500' what will 90 of them do?

Pull up on the pitch control.

@GeeBee 1, 2, 3  The WRONG thing.  They need to be trained better.  Push … like ALL 100 glider pilots will do.

The time to think about it isn't when it just happened.  It's in training and again before the power is pushed up.

[GeeBee]

1 hour ago, Blue on Top said:

1.  In 3 words, more available performance.  As I mentioned previously, each airplane is different and each design has different reasons for different systems.  For an airliner that only flies out of few, paved, runways that are much longer than is required, sure, don't let them stall …. but then the pilots won't … better not go there.  You may remember an accident at the Paris Airshow with an A320 that those pilots might disagree with you.  Again, full automation is coming.  Pilots rely on systems to fly the airplane way to much the way it is now.

2. I ordered the book.  I've read the actual transcripts and reviewed the actual cockpit data.  I'm looking forward to reading your friend's book.

3. The training should not be on how to turn the autopilot on and use the FMS.  It should be on what happens when the automation fails and why the automation failed.  Had AF447 crew known that AOA and airspeed are totally independent, would they have still ignored the stick shakers?  They knew some things as they turned the pitot heaters on during the descent.

Bottom line:  I'm looking forward to reading the book.   AND finding a solution(s) that doesn't allow accidents like this.

So tell me how the Paris Airshow accident happened.

 

[Blue on Top]

7 minutes ago, GeeBee said:

So tell me how the Paris Airshow accident happened.

@GeeBee Google it.  Up against (AOA) no-stall limit.  I'm guessing you have a different reason.

Is that a "normal" operation?  No, not in my opinion; it was showing off aircraft performance.  Is it a possible emergency go-around maneuver?  Yes.

[GeeBee]

I've come to the conclusion you don't know what you are talking about with respect to Airbus. AF 447 did not turn on pitot heat on the way down. The Airbus high probe heat is continuous from engine start to shut down. You have to make an affirmative selection to OFF, which would trigger an ECAM warning of OFF and there was no such ECAM. They did turn on WING ANTI -ICE, which was appropriate. There is NO indication in the CVR or FDR that the pitot heat was switched off or on, only that the data was invalid from the pitot.

In Paris it was indeed a demonstration that the airplane would not stall. The pilot flew the airplane with the stick full aft showing it would not stall, except it will sink with insufficient power (being on the backside of the curve) and when it sank below 100' RA Normal law removes stall protections because the airplane must land at some point. So as the demonstration went through 100' it stalled because the airplane reverted to direct control. Any Airbus pilot who has landed in a crosswind can tell you this fact because you cannot slip the airplane until direct control is established.

[Hank]

4 hours ago, GeeBee said:

In Paris it was indeed a demonstration that the airplane would not stall. The pilot flew the airplane with the stick full aft showing it would not stall, except it will sink with insufficient power (being on the backside of the curve) and when it sank below 100' RA Normal law removes stall protections because the airplane must land at some point. So as the demonstration went through 100' it stalled because the airplane reverted to direct control. Any Airbus pilot who has landed in a crosswind can tell you this fact because you cannot slip the airplane until direct control is established.

Anytime automation won't allow me to do what needs to be done is a problem! Airplane, car, equipment at work or even CD player in the living room. When I activate a control, I expect action, not "I'm sorry, Dave, I can't let you do that."

[Blue on Top]

9 hours ago, GeeBee said:

Might want to take a look at this from an instructor I know. I would note he talks about a friend of his killed at KFFC in a stall spin after engine failure. Now he was not only well trained, he was a CFI-I

@GeeBee  It's a great video.  I've watched it several times before … and now once again.  Love it.  It's also a great reminder that we don't need more stall or spin recovery training … it won't help.  (side note: everyone should do at least one spin.  It won't help you in the pattern, but maybe it wont scare you as much if it actually happens … at a high enough altitude).  We need training to know what to do BEFORE the throttle is moved forward for takeoff.  And train that.  And train that.  And train that.  And train go-arounds.  And train go-arounds,  And train go-arounds.  And train about departure stalls … with and without an engine failure.  And train that on climb out if one banks the airplane they must be able to accept some loss of rate of climb. Etc.

I don't agree with the 1.404 Vs, and pilots should not be taught this.  Airlines (and GA) should be teaching 1.3Vs, that is what their landing performance is based on.  Too many people add knots for crosswinds, knots for gust (good idea), knots for "safety" (which is not true), knots for grandma, knots for etc.  This is a major reason for airplanes going off the end or side of the runway.  And for Mooney airplanes floating into the next county.  I would name an OEM that it happens to more often than others, but it's not the OEM's fault.

On the 1.404 Vs, in particular, it is adding knots where knots are not required.  30 degree bank does not equal 8% stall speed increase; 60 degree bank does not equal 40% stall speed increase.  Those numbers are only for level flight and pulling those related G-loads … 2G in the 60 degree bank case.  People might be banking 60 degrees in the base-to-final turn but are not pulling 2G.  In fact they are probably pulling slightly over one G.  The problem there is the rate of descent is very high … and pulling only tightens the spiral.

BTW, the base-to-final turn produces about 5% of the fatal accidents.  The Industry is finally looking at the real numbers and starting to realize this fact.  Takeoff, go-around and moose turns (low altitude, ground-reference maneuvers … looking at your house, girl friend, showing off, etc.)

[Andy95W]

1 hour ago, Hank said:

Anytime automation won't allow me to do what needs to be done is a problem! 

At no time does Airbus automation not allow you to do what needs to be done, unless there is a failure of hardware.  When hardware does fail, the Airbus reverts to modes where the computers, progressively, give less help to the pilot.  Essentially, it hands back more and more control to the pilot without computer assistance.

The thing that the Airbus automation does is prevent the pilot from doing what does not need to be done.  In the Air France accident, the pitot tubes iced over which gave bad information to the automation and the pilots. At the time, that was an unknown failure mode which we now train for.  That system has also been redesigned to provide a means to counter the failure of pitot information.

In the Paris Airshow crash, the automation once again did not prevent the pilot from doing what needed to be done.  In the landing mode, it was giving more and more control back to the pilot, who then reacted poorly.

[Blue on Top]

36 minutes ago, Andy95W said:

1.  When hardware does fail, the Airbus reverts to modes where the computers, progressively, give less help to the pilot.  Essentially, it hands back more and more control to the pilot without computer assistance.

2. The thing that the Airbus automation does is prevent the pilot from doing what does not need to be done.  In the Air France accident, the pitot tubes iced over which gave bad information to the automation and the pilots. At the time, that was an unknown failure mode which we now train for.  That system has also been redesigned to provide a means to counter the failure of pitot information.

In the Paris Airshow crash, the automation once again did not prevent the pilot from doing what needed to be done.  In the landing mode, it was giving more and more control back to the pilot, who then reacted poorly.

@Andy95W  Thank you for your level-headed explanations.

1.  I agree with your statement.  But, if this were known and trained, why did the crew continue to keep the airplane in the stall?  AOA told them the aircraft was stalling/stalled (until airspeed went below the low airspeed threshold and invalidated AOA, too, but it too came back on the way down … when the pitot tube heaters caught up with the ice pellets and cleared again).

2.  Yes, again.  As a very educated guess, I would highly doubt that simultaneous failure of 3 pitot tubes was ever analyzed before this event.  It would also have to be a failure (icing) that completely blocked the pitot tubes, but at sometime the drain holes were open(ed) to bleed off the indicated airspeed.

3.  So I can learn, are you saying that either "normal law" allowed the airplane to stall or that the airplane left "normal law" and allowed the airplane to stall?

Thanks! -Ron

PS.  Pitot heat on or off is not relevant to the cause of this accident.  All 3 pitot tubes were overwhelmed with ice.  Pitot tube certification regulations (I know in the US) have been changed to handle this new requirement. 

Edited February 27, 2020 by Blue on Top
Add the PS