Spin Training

[photofly]

There should be NO inputs to the ailerons or rudder at this point ... Maintaining a heading into an out of a stall is pointless and counterproductive.

OK. That clears up your position. You're going to need to get the Flight Test Standard(s) changed, though. As far as primary training is concerned it's really the only document that counts.

[mcrit]

Hi triplese7en. You've posted some food for thought. I'd like you to consider the following situations, (all of them in a light straight wing trainer).

- the wing is right at its critical AOA, and starts to drop; you pick it up with aileron. What has happened to the AOA of that wing tip, the amount of lift that wing is producing, and the roll rate?

- the wing is stalled, and starts to drop; you pick it up with aileron. What has happened to the AOA of that wing tip, the amount of lift that wing is producing, and the roll rate?

[Colonel Sanders]

As a pilot, you have a choice to make.

If you want, you can hoist the Jolly Roger
and say, "F__K THE MAN! I DON'T CARE
ABOUT THE RULES! I'M GOING TO DO IT
MY OWN WAY, AND DAMN THE CONSEQUENCES!"

You can do that. Or you can choose to obey
the regulations.

Let's start with the PPL Flight Test Guide,
TP13723E. Under exercise 12, it says
for Stall:

http://www.tc.gc.ca/eng/civilaviation/p ... 2-2451.htm

Performance Criteria
Assessment will be based on the candidate’s ability to:
e. stall the aeroplane;
f. maintain directional control;
g. promptly and smoothly recover using control applications in the proper sequence;

Note that it does not say what the
"proper sequence" is. I guess TC
thought it was so obvious, it didn't
need to be repeated. I would agree.

Keep in mind CAR 405.14:

Flight training that is conducted using an aeroplane or helicopter shall be conducted in accordance with the applicable flight instructor guide and flight training manual or equivalent document and the applicable training manual on human factors.

That's pretty straightforward, even for
the peg-legs around here with parrots on
their shoulders, waving their swords in the
air. Note the "shall be conducted" part.

What does the FIG (TP975E) have to say,
about stalls?

(f) Recovery with and without power:
(i) control direction with rudder;
(ii) unstall aircraft with forward movement of the control column;
(iii) level wings with ailerons.

There's your "proper sequence", which is referred
to by the PPL Flight Test Guide.

If that doesn't make it blindingly clear enough for
you, get out TP1102E, Aeroplane Flight Training Manual,
which is also specified by CAR 405.14. See the
Exercise 12 chapter on Stalls, where it says, for
Entry and Recovery:

"Keep straight with rudder control".

It repeats this:

"Keep straight with rudder. Use ailerons if permitted
by the Aircraft Flight Manual".

Again, the FTM is very clear on the "proper sequence".

Let's get out the applicable "Owner's Manual" for the
1975 C172, which I have too much time on. If we look
up stalls in the index, it refers us to section 2-17 which
does NOT authorize the use of ailerons during stall recovery.


Now, you probably think that I'm some sort of candy-@ss.
You probably don't think that I know very much about
stick and rudder flying. You probably don't think that I
spend much time in high alpha.

Here's something I routinely do. I want you to try it,
and get back to me.

Take off. Accelerate but do not climb. At the end of
the runway, pull vertical - minimum +4 G's, +6 is better -
and hold the vertical upline until your airspeed decays.

Now, I want you to recover from that. If you use my
technique, you will live. If you use your technique, you
will die.

Please don't give advice to people that may result in
them dying. That's really not very responsible. And
you probably don't care, but you are also coaching
them to contravene regulations.

[Old Dog Flying]

Looking at the overly lengthy diatribe on this subject makes me think that we are in a fully developed spin from which we will never recover....It is very easy to quote from any manual and use it to emphasise your arguement but I'll take CS's advice any day over that of an airline driver. Air France 447 comes to mind.

Youth and arrogance will never replace old age and cunning.

[Big Pistons Forever]

The last post CS wrote is IMO the only one that is of practical value to an actual flight instructor that is engage in instructing, actual students. The message may be delivered in CS's unique "style" but I strongly believe his advice is both accurate and practical and should be heeded.

And yes, unlike many of the "experts" pontificating on this subject, I am an actual instructor engaged in actual flight instruction, and will be airborne in the mighty C 172 with a student in about 2 hours.......if the rain stops.

[Cat Driver]

It is Sunday morning and I thought this discussion would have been finally finished......but alas I was wrong.

I must comment on this because I feel the advice has the potential to be deadly.

When the wing drops in the stall, the airplane doesn't really roll around its longitudinal axis. It sort of falls off to one side as if it's falling/rolling off the top of a ball. Due to that, its heading will change. Who cares?!

I do.

Once you've recovered from the stall, roll wings level on that heading and pull up. Maintaining a heading into an out of a stall is pointless and counterproductive. The best way to recovery is essentially let the plane do what it wants to do.

No, absolutely no, the flight controls allow me to decide where my airplane is going.

Triplese7 I am sure you think you have discovered something new that aviation had not figured out before you found a better way, unfortunately you are wrong, Colonel S was correct and I will re post what he said as I have the same opinion.

If I listened your advice, I would have died
a long time ago.

[photofly]

What are y'all going to say to triplese7en if Transport Canada does change the FIG and the flight test criteria?

I'm just askin'.

[Colonel Sanders]

I rather liked the bit about the eye patches, parrots and swords.

[triplese7en]

Hi triplese7en. You've posted some food for thought. I'd like you to consider the following situations, (all of them in a light straight wing trainer).

- the wing is right at its critical AOA, and starts to drop; you pick it up with aileron. What has happened to the AOA of that wing tip, the amount of lift that wing is producing, and the roll rate?

- the wing is stalled, and starts to drop; you pick it up with aileron. What has happened to the AOA of that wing tip, the amount of lift that wing is producing, and the roll rate?

1) AoA increases, lift increases, roll rate increases in the direction of the aileron deflection. I've done it many times. It's possible because of a feature called washout.

2) AoA increases, lift either increases or decreases, roll rate either increases or decreases in the direction of the aileron deflection. Again, even with a 'stalled' wing, the entire wing is not necessarily stalled. At the point where the airplane exhibits stall symptoms, the wingtips are not stalled on a Cessna trainer, as evidenced by normal roll control - there is no reversal.

As I've mentioned before, I'd never be able to convince a student (by demonstration) that they shouldn't use ailerons in a stall because if I attempted the demonstration it would fail every single time! Meaning, the airplane would actually roll towards the aileron deflection. I explain to the student the reason why they shouldn't use ailerons in a stall and I ensure that they don't use ailerons in a stall.

[triplese7en]

To everyone on here: you are clearly NOT reading my posts in full and looking at the references I provided. If you're too lazy to do that, that's fine. But kindly be too lazy to reply also. It's annoying to have to repeat something and make corrections I shouldn't have to if someone actually did read what I wrote.

Thank you kindly!

[photofly]

It's possible because of a feature called washout.

It's nothing whatsoever to do with washout.

It's because lowering an aileron changes the camber of the wing section. As you increase the camber of the wing you raise the critical AoA. If the "goalpost" is the critical AoA and the "ball" is the angle of the airflow to chord-line then lowering an aileron moves the ball in the direction of the goalpost but also moves the goalpost the same amount. The ball doesn't get any closer to the goal.

It's possible to encourage flow separation and loss of lift by lowering an aileron if the aileron is hinged sharply so there's a sharp bend in the top surface when the aileron is lowered. That's a slightly different effect though and depends on the wing design.

[Colonel Sanders]

if Transport Canada does change the FIG and the flight test criteria?

Hm. What are you going to say to Jerry Rice
if he has a sex change operation?

I'm afraid I don't spend a whole lot of time
worrying about it

[photofly]

Who's Jerry Rice?

[Cat Driver]

I feel like I am on Coast to Coast AM because this conversation is getting so far out there....I am beginning to get the feeling I am in a time warp and am losing my sense of where I am.

Did I read this all wrong triplese7en?

When the wing drops in the stall, the airplane doesn't really roll around its longitudinal axis. It sort of falls off to one side as if it's falling/rolling off the top of a ball. Due to that, its heading will change. Who cares?!


Once you've recovered from the stall, roll wings level on that heading and pull up. Maintaining a heading into an out of a stall is pointless and counterproductive. The best way to recovery is essentially let the plane do what it wants to do.

Am I wrong in my making sure I am flying the airplane instead of the airplane flying me?

[triplese7en]

Colonel - good morning!

You can do that. Or you can choose to obey
the regulations.

First off, the Canadian documents that you're referencing do NOT conform to all the other documents across the spectrum of aviation that I have referenced. There are Canadian documents and FAA documents that it does not agree with.

I will rewrite something I wrote earlier:

All the references I've quoted throughout this have specifically mentioned to not use uncoordinated controls on stall recovery, to use coordinated controls on stall recovery, emphasized reducing pitch by using the elevator, and said that minimizing altitude and restoring normal pitch and roll attitudes should be secondary considerations. All these references span from general aviation airplanes (FAA Flying Handbook), turbine commuter airplanes (Advisory Circular on Training and Checking Practices for Stall Recovery), and airliners (Airbus/Boeing Flight Test Lecture). They're all saying essentially the same thing and you're telling me that the fundamental stall recovery procedure is different for each airplane? It is most definitely not different. It is only the specifics, such as when and how to add power, that vary between aircraft type.

Colonel, if I am wrong, and as you said if you followed my advice you'd be dead - I think that's a pretty serious case - maybe we should be contacting all these people to tell them that they're wrong?

I'm aware of all your quotes from the FTG and the like. The wording of "control direction with rudder" is interestingly NOT specific. In accordance with the way the other exercises are written in the FTG I would assume that it should say: "control heading with rudder to maintain examiner specified heading +/- 10 degrees". At least that's what everyone on here is reading when they read "control direction with rudder". I find it slightly interesting why they didn't write it to be more specific.

Now, you probably think that I'm some sort of candy-@ss.
You probably don't think that I know very much about
stick and rudder flying. You probably don't think that I
spend much time in high alpha.

You do know a heck of a lot about stick and rudder and high alpha.

But you've missed the point as to what type of training I'm recommending this to.... hint: it does NOT include aerobatic training!

Take off. Accelerate but do not climb. At the end of
the runway, pull vertical - minimum +4 G's, +6 is better -
and hold the vertical upline until your airspeed decays.

Now, I want you to recover from that. If you use my
technique, you will live. If you use your technique, you
will die.

That sounds like quite the aerobatic maneuver! As I've said, I never intended this to be used in an aerobatic environment. None of the references I have used throughout this have mentioned or intended this recover to be used from some sort of aerobatic maneuver. Colonel, this is not for aerobatics!

I have flown aerobatics - you are I'm sure much better than I at it. But I do recognize that you will need to use rudder in the exercise you described and I would most definitely listen to and follow your technique. Just to be clear - I would follow your technique to perform that aerobatic maneuver.

Old dog -

I'll take CS's advice any day over that of an airline driver. Air France 447 comes to mind.

Geez! Well AF447 was always in my mind when writing what I did. Did you miss the Macleans article 'Cockpit crisis' that I posted?

Cat -

Triplese7 I am sure you think you have discovered something new that aviation had not figured out before you found a better way

I don't think I can claim that I've discovered something new that aviation hasn't figured out when the references that I'm using come from 2005! I'm virtually quoting what is written in those documents and passing it on. If you have a problem with what is in those references I'd like to discuss that. Don't shoot the messenger!

[photofly]

I feel like I am on Coast to Coast AM because this conversation is getting so far out there....I am beginning to get the feeling I am in a time warp and am losing my sense of where I am.

I think you are in a time-warp. Two hours ago you posted it was Sunday morning. I'm pretty sure the rest of us are somewhere at Tuesday.

[triplese7en]

Cat -

Am I wrong in my making sure I am flying the airplane instead of the airplane flying me?

You're interpreting what I'm saying incorrectly. I know exactly what you're talking about and no, you never want to let the plane fly you. That, to me, means you're not in control.

What I'm talking about is letting the airplane do what it wants to naturally. When you pull the power to start a descent and the nose drops, do you say: "F*ck no airplane! I'll be the one to push the nose down when I want to!!" ? I assume you don't.

What I'm saying is to work with the plane, fighting against it is not always a good idea! If you've got "aerobatics" in your head, please stop. I can't stress enough that aerobatics is NOT what I'm talking about.

[photofly]

What I'm talking about is letting the airplane do what it wants to naturally.

Yeah, except that's not going to work if the aircraft is in a stall because it's badly out of trim, like when you add full power with flaps down on a go-around.

You have to be careful with generalizations.

[mcrit]

1) AoA increases, lift increases, roll rate increases in the direction of the aileron deflection. I've done it many times. It's possible because of a feature called washout.

Look at the lift vs AOA graphs again my friend. If you exceed the critical AOA your lift decreases, which in this case means that you roll more into the dropped wing.

AoA increases, lift either increases or decreases, roll rate either increases or decreases in the direction of the aileron deflection. Again, even with a 'stalled' wing, the entire wing is not necessarily stalled. At the point where the airplane exhibits stall symptoms, the wingtips are not stalled on a Cessna trainer, as evidenced by normal roll control - there is no reversal.

Sorry, but no. When the wing is fully stalled any increase in AOA, such as down going aileron, will result in a reduction in lift and further wing drop. If you don't believe me, find and instructor who is competent in spins (I am available if you find yourself in the YWG area) and ask him to show you a spin with various aileron configurations (pro spin, anti spin and neutral).

As a further to my original question; what happens to the drag on the wing in each of the situations I originally posed?

Who's Jerry Rice?

A guy who got a sex change and now goes by the name Condoleezza Rice.

http://www.veteranstoday.com/2012/09/09 ... za-rice-7/


Condoleezza

[Cat Driver]

I think you are in a time-warp. Two hours ago you posted it was Sunday morning. I'm pretty sure the rest of us are somewhere at Tuesday.

That was deliberate, I wanted to see how many people here actually think about what I post.

[triplese7en]

I've got another reference for y'all! It's the FAA Practical Test Standards - their form of our Flight Test Guide.

Under power-off stalls, it says this:

1. Exhibits satisfactory knowledge of the elements related to power-off stalls.
2. Selects an entry altitude that allows the task to be completed no lower than 1,500 feet AGL.
3. Establishes a stabilized descent in the approach or landing configuration, as specified by the examiner.
4. Transitions smoothly from the approach or landing attitude to a pitch attitude that will induce a stall.
5. Maintains a specified heading, ±10°, if in straight flight; maintains a specified angle of bank not to exceed 20°, ±10°; if in turning flight, while inducing the stall.
6. Recognizes and recovers promptly after a fully developed stall occurs.
7. Retracts the flaps to the recommended setting; retracts the landing gear, if retractable, after a positive rate of climb is established.
8. Accelerates to VX or VY speed before the final flap retraction; returns to the altitude, heading, and airspeed specified by the examiner.

I've highlighted a few points on there.

1) The candidate is to maintain a specified heading while inducing a stall.

2) On recovery, the candidate is to "return to the heading" specified by the examiner.

Nowhere does it say that the candidate must maintain a specified heading throughout the stall exercise! It clearly gives allowance for a heading deviation on the stall recovery. This aligns nicely with what is written in the FAA Airplane Flying Handbook where, as I've quoted a few times, it specifically states the method I've talked about through this entire thread.

Now, Colonel, if we were in the good ol' US of A, the method I'm suggesting to be used would conform to what's written in the Airplane Flying Handbook, AND what's written in their Practical Test Standards. Your argument falls apart.

What I'm saying, and have already said, is that the Canadian documents do NOT agree with each other, and do not agree with any of the other documents in aviation that pertain to stalls. Last time I checked, the aerodynamics aren't different up in Canuck-land!

photofly -

Yeah, except that's not going to work if the aircraft is in a stall because it's badly out of trim, like when you add full power with flaps down on a go-around.

You have to be careful with generalizations.

Yes, clearly. If you're going to come up with some different scenario and apply what I've said to it, then I could do the same for anything anyone has ever said too and make what they're saying to be incorrect.

[mcrit]

I think you are in a time-warp. Two hours ago you posted it was Sunday morning. I'm pretty sure the rest of us are somewhere at Tuesday.

That was deliberate, I wanted to see how many people here actually think about what I post.

I did read it, and just chalked it up as an "old guy moment".

[Trematode]

In the interests of trying to find some common ground I think what triplese7en is advocating is that less emphasis be put on the use of rudder in a stall when there is wing drop, and more be put on decreasing the angle of attack.

In practice you would perform both actions simultaneously, but one could argue -- as I believe triplese7en is (correct me if I'm wrong) -- that only one of these actions will actually recover from the stall.

As an instructor, I used to also emphasize decreasing aoa first and foremost, with rudder control of uncommanded roll something that you layer on top of the stall recovery.

If he is saying "to hell with the rudder, use aileron", then I can't agree.

[triplese7en]

mcrit -

Look at the lift vs AOA graphs again my friend. If you exceed the critical AOA your lift decreases, which in this case means that you roll more into the dropped wing.

I'm very familiar with what the graphs look like. You clearly do not realize that a wing's AoA vs CL is not able to be depicted on a single graph - a single graph can represent one section of the wing, not the entire wing. As I've already explained, a feature called washout makes what I said to be true.

Clearly you haven't worked much with stalls in a Cessna before because if you were to do what I said, you would find your little mind to be blown.

When the wing is fully stalled any increase in AOA, such as down going aileron, will result in a reduction in lift and further wing drop.

If the entire wing is stalled then what you say is correct. However, if you're entering a stall in a Cessna trainer, the entire wing will NOT be stalled, which is why you will have roll control when you feel yourself in the stall. Please stop arguing this and go out and try it. Again, it's called washout.

Notice how I said that it could go one of two ways? It depends if the aileron section is stalled. Sometimes it is, so in that case it will follow what you say.

Please tell me you understand how a wing stalls? If you need a reminder, check out this video: http://youtu.be/WFcW5-1NP60

As a further to my original question; what happens to the drag on the wing in each of the situations I originally posed?

I'm done with your little question period. You clearly don't know what you're talking about.

Trematode -

If he is saying "to hell with the rudder, use aileron", then I can't agree.

The fact that you say that really ticks me off. I have spent so much time explaining throughout here (specifically stating in at least one post) that you should not use only aileron, or only rudder. I've made it extremely clear that you're to use coordinated inputs on the recovery from the stall.

In practice you would perform both actions simultaneously, but one could argue -- as I believe triplese7en is (correct me if I'm wrong) -- that only one of these actions will actually recover from the stall.

I'm just going to regurgitate what I've already said, and what the references I've used have said since 2005.

"Effective stall recovery requires a deliberate and smooth reduction in wing angle of attack. The primary pitch control (elevator) is the most effective control for recovery from high angle of attack flight under all flight conditions."

AoA must be reduced. The elevator is the most effective control at reducing AoA. Therefore, the elevator should be used to recover from the stall.

This requires that the primary pitch control (elevator) be used to initiate a stall recovery. The goal of minimizing altitude loss should be a secondary consideration, until a positive stall recovery has been assured.

The bold is theirs.

Again, can I ask that everyone actually reads what I'm quoting and linking to on here? If you refuse to (as evidenced by your responses) then this is really going to go nowhere.

[Trematode]

Again, it's called washout

What happens to wash out when the flaps are deployed?

I am trying to help, man -- I read what you wrote. Just to be clear though... You've stalled your 172, your wing is dropping: what is your response?

If you explicitly state your answer without citing FAA advisory circulars I am betting you all are in agreement more than you think.