NimpoCub,
Mike,
Ask the airplane what it wants to do. If you fight it, it will shake and moan and finally dump you.
Jim

Both are good skills to know how to use and to be proficient with. If already slowed down, I apply the power/ flaps method. If faster or already powered up like pulling up from a low pass, I use the ag turn. Both have their advantages.

The power/flaps turn is the traditional turn I was taught many years ago in mountain flying instruction. That turn works well and is the one I used most when flying the 182. In the Bearhawk, I find myself using the ag turn most often for the reasons Jim describes; I agree it is less effort to execute and thereby reduces pilot stress.

I'm glad to have both of them in the skills box and appreciate this discussion!

A cessna182 here.
I was thought by an instructor, slow down full flaps and full power at about 60 degrees bank.
Now my question is why 40 degrees of flaps instead of 20?
Isnt it 40 more drag?

I see nosedragger posted he does the same full flaps too in his 182.

Flaps 10 creates more additional lift than it does induced drag. Flaps 20 creates close to equal additional lift as it does additional induced drag. Flap settings above this typically create more drag than lift. In a steep turn you're raising your stall speed because of the additional wing loading required to maintain vertical lift equal to weight.

You'd theoretically want flaps 20 to maximize additional lift while minimizing additional drag. It'll give you more excess power which you can then use to help maintain your altitude.

That's not discrediting anyone else's technique, just a description of my understanding of the aerodynamics involved in the flaps/power/constant altitude turn method.

I do think both have a place and a time when they're valuable.

The most important part of flying canyons is to slow down. Whether you're flying a 182 or a Cirrus, the slower you can reasonably go, the tighter radius the turn will be at any given bank angle. The difference between a 90 knot 180 degree turn and a 70 knot 180 degree turn is significant--but increase the higher number to 120 or 130, and it takes lots and lots of real estate to turn around in.

For myself, I like to slow to no more than my normal downwind speed, which is about 80-85 mph (70-75 knots). Ideally I'll minimize my bank to around 35-40 degrees, but it may be steeper, depending on the canyon. Much more than a 45 degree bank, however, risks losing situational awareness, and depending on the load and airspeed, it also risks getting too close to the stall. I'll often use 10 flaps, only to add lift. 20 is OK on a 182, just like you use for a soft field take off. But the more flaps you use, the more power you need to keep from losing altitude.

I recommend that you try turning 180 degree turns at different airspeeds and different degrees of bank with different flap settings, but I would not recommend more than 20 flaps. Part of a good canyon turn is being comfortable with it, so that you can immediately do one if necessary, without thinking "what do I do now?" Do all this, as with any new maneuver, with plenty of altitude, so that you have room to recover from any inadvertent stall or great loss of altitude.

Cary

Cary will call bullshit on this, but I found it applies to a 182 pretty well:

http://www.pilotfriend.com/safe/safety/canyon_turn.htm

Box Canyon Turn - Introduction

The box canyon turn varies from the steep turn in that it is either performed from level flight at such a slow airspeed that an unintentional stall is imminent, or some excess airspeed at the beginning of the manoeuvre allows the nose to be raised above the horizon prior to initiating the bank and the airspeed, during the turn, will be too slow to sustain level flight.

We have learned the airplane always stalls at the same critical angle of attack. When banking the airplane, the stall speed increases (remember? it increases as the square root of the wing load factor). Whenever the airplane is banked in a coordinated turn, it is balancing the centripetal force (horizontal lift component that causes the turn) and the centrifugal force (the force of the turn). The turn takes place because the centripetal force pulls the airplane towards the inside of the turn.

Without a compensating increase in the amount of total lift during a turn, the airplane will lose altitude. The total lift (lift) is divided between a vector force that sustains the weight of the airplane and its contents (weight). The portion of lift that is directed sideward (centripetal force) causes the turn. The centrifugal force acts towards the outside of the turn.

To maintain level flight while turning it is necessary to increase back pressure (more lift equals an increase in angle of attack). This increases the load factor and stall speed.

Some pilots get into trouble with the box canyon turn without realizing it because they have been "conditioned" to maintain level flight when performing steep turns.

Box Canyon Turn - Procedure from Cruise Flight

The first time a pilot has to perform a box canyon turn in a true life situation, he may feel like the lady who climbs on a stool to avoid a mouse scampering across the floor. A little scream to get the adrenaline flowing wouldn’t hurt either.

The box canyon turn could be described as a combination of the steep turn and wing over (when entered at or near cruise airspeed). The nose is raised above the horizon, but nowhere near the 40-degree attitude of the wing over. About five to 20 degrees is about right, depending on the airspeed.

This does two things for you. First it trades airspeed for altitude and second, it slows the airspeed for a smaller radius of turn.

At the same time, full power is added and full flaps (providing the airspeed is within the flap operating range) are applied while beginning the bank. The bank will be a minimum of 60 degrees and may approach 90 degrees.

To insure that the g-load factor is not exceeded during the steep bank it is necessary to relax the back pressure once the bank passes about 45 degrees. The back pressure is not increased again until the bank passes through about 45 degrees toward zero degrees during the rollout.

Initiate the turn - the procedure requires coordination to accomplish all items at the same time:

Increase pitch attitude
Increase power
Begin a bank
Apply full flaps

At approximately 45 degrees of bank increasing toward 60-90 degrees:

Relax back pressure from the control wheel

Recovery - at approximately 45 degrees of bank, decreasing from 60-90 degrees:

Increase back pressure on the control wheel to arrest any loss of altitude.
When the airplane is in a position that allows, reduce flaps to one half

Box Canyon Turn - Procedure from Climbing Flight

When operating near cruise airspeed the box canyon turn was described as a combination of the steep turn and wing over where the nose was raised above the horizon.

Hopefully, the airspeed is near the best rate-of-climb speed or best angle-of-climb speed. This is usually a critical situation because the airspeed will probably be slower than Vy or Vx due to the “short-arm” effect.

While applying full power and full flaps, a bank is established at a minimum of 60 degrees. Again the bank may approach 90 degrees.

Previously we stated that the back pressure was relaxed to insure that the g-load factor was not exceeded. This is not as much of a problem at low speed, but it still exists. At the slow speed the airplane will probably stall before it exceeds the structural limitations. The main reason for relaxing the back pressure now is so the airplane does not stall. The back pressure is not increased again until the bank passes through about 45 degrees toward zero degrees during the rollout.

Initiate the turn - the procedure requires coordination to accomplish all items at the same time:

Maintain pitch attitude initially
Increase power
Begin a bank
Apply full flaps

At approximately 30 degrees of bank, increasing toward 60-90 degrees:

Relax back pressure from the control wheel
The pitch attitude will fall below the horizon

Recovery - at approximately 30 degrees of bank, decreasing toward zero degrees:

Increase back pressure on the control wheel
Reduce flaps to one half

Natural Horizon

The natural horizon is used to teach flying by outside visual reference. An instructor demonstrates a climb attitude at the best rate-of-climb airspeed. The student mimics this attitude. The airspeed indicator can be covered and the student, by noticing the pitch attitude in relation to the horizon (where the horizon intersects the side of the nose cowling), is able to fly at the best rate-of-climb airspeed within plus or minus one knot. Learning the “climb attitude” can provide for a very accurate climb speed, without looking at the airspeed indicator.

The instructor also demonstrates where is the nose in relation to the horizon in level flight, where are the wings in relation to the horizon in level flight, and where is the nose in relation to the horizon in a steep turn (left and right turns).

This natural horizon is easy to use in the flatlands as a reference for basic attitude flying. In the mountains, the natural horizon may disappear. By visualizing a horizon, basic attitude flying can still be maintained. The base of the mountains, at least six to eight miles away, represents the natural horizon.

What if the airplane is closer than the six to eight miles? Visualization must be used. Perhaps the mountains at least six to eight miles in the distance are visible out the side window. Project the same horizon visually to the front of the airplane.

Summary

The box canyon turn is an emergency procedure. It is best to practice it with an experienced instructor prior to the time when it becomes necessary as a life-saving manoeuvre.

Without practice it is very easy to get into an accelerated stall condition that will exacerbate the original situation.

Caveat

You must exercise caution in using full flaps during the practice of the box canyon turn and for drainage searches because of the possibility of the flaps failing in the extended position.

For practice you may want to restrict the use of flaps because of the real possibility of the flaps failing to retract. It is possible to demonstrate and learn the box canyon turn without full flaps where the same technique, using full flaps, is applicable to a real "tight" or emergency condition.

This guy has a better command of the English language than I, but that is basically what I teach. His canyon is obviously level because he doesn't allow for the extra vertical space we have where the canyon is formed by two ridges closing to form a pass in high mountains. In this case there is no need to for the completion of the canyon turnaround at the same altitude as the beginning. I have always felt safer erring on the side of losing altitude in the energy management turn. When riding the downwind ridge at say 50 feet above and 50 feet upwind in an attempt to get up to the pass, turning back down stream or drainage generally provides at least a thousand vertical feet to play with. This can become important if we have waited until a 90 degree bank is necessary to miss the upwind ridge or get into the valley (poor planning). Again, when already at near ceiling density altitude and full power, we will already be pitched up to Vy. In this case no pitch up is necessary or possible We are already slow enough to begin the turn. Now it becomes even more important to allow the nose to go down naturally by holding no back pressure in the turn.

Cary will call bullshit on this

Nah. In fact, I'll print it out and put on my panel, to refer to if I find myself needing to refresh myself as I run out of canyon and just before I start my turn.

Seriously, I really don't like the full flap part. I think it's a little complicated for most folks, and I prefer simplicity. It's like any other tool in your emergency procedures tool box, it needs to be something you can immediately use if necessary. That means some practice, but even if you haven't practiced it in quite awhile, it needs to be something easily enough recalled so that the outcome will be acceptable.

Cary

And if you do practice this, don't be tempted to cheat with bottom rudder.

Modern airplanes, except Ercoupe, give a false sense of doing alright with too little rudder in the turn. That is one reason for 45 degree bank Dutch rolls. No faking it here. As we turn, the nose goes down naturally unless we hold back pressure. That is another reason for not messing with full flaps. We need strong rudder usage in steep turns. If the bank is increasing, the rudder must increase. We can check proper rudder usage while looking at the terrain by checking to see that the rate of turn is increasing with the bank. If the nose is hanging up, we need to push it around.

When teaching steep energy management turns, i find most pilots letting the rate of turn slow as the bank increases. I find a reluctance to get the nose around and onto target, in this case the middle and bottom of the canyon. The target is not the upwind canyon wall. Forget going over that. In the mountains we always want to know which way is down hill or down drainage because in an emergency canyon turnaround, that is the target. I have said it a thousand times, "push that nose around. Don't let the nose push you around."

Contact, I hope you didn't just suggest skidding the turn to get the nose around.

Nosedragger, No, but I find 99% of pilots slip around in steep turns with the nose hanging up and relative wind noises and a lot more pressure in the butt cheek toward the turn. I am low and don't have time to look at the ball, but ride with guys in modern aircraft. Most just rest their feet on the pedals. Have them do Dutch Rolls, going to 45 degree of bank each way while holding the point. They swing the nose all over the place because they don't use enough rudder, especially bring the wing back up. Adverse yaw will play hell with the airplane and down low it will really, really make a difference.

I just haven't seen the skidding turn problem that many instructors are worried about. Of course in low ground effect, that is the only safe way to turn. Low ground effect makes up for the loss of lift in the skid. We keep the wing level with aileron and push the nose where we want to go with rudder. If you have decided to go under rather than over the wire and the pole is to close, you rudder turn away and then toward the pole. That sets you over so you can go under. An airplane doesn't fall down if skidded.

In the fourth or fifth hour of spraying in one day, your knees start shaking like the football boys when the use that sit and push with legs weight machine. You are pushing hard on those rudders in tight turns.

OK as I understand were doing a canyon turn!
If you are doing a canyon turn I would say that there should be a steep ridge rising to your right and just to your left there should be another steep ridge rising to your left, your wing should be almost in the rocks or trees, in front of you is rising terrain that you cannot out climb or there is a overcast layer above you blocking the pass your trying to get over or you have just come around a corner and it's 00 to the ground!
If it is none of these it's not really a canyon turn that you need, am I wrong here?
If you are in this position you should not be in cruise configuration PERIOD!
My experience with this is Rainy Pass, Merril Pass, Schemburger Pass, the Alsek and Tatshenshini River drainages. All have spots where you can slow way down and poke your nose in to see if you can get through.
Merril is the ugliest as when you are there you have to start you 180 turn and at 90 you can see if it's good enough to go through , if not finish your turn and find another way! If you are not in your turn when you look through, you have just joined all those others on the hillside!!
I have not done much of that down here but what little I have has been mainly in the Northern ID./ MT area.
I have not done any of this in the cascades because when ever it get very bad there it is always plugged up on the west side in my experience( which is very limited with them)!
Saying this I have never been at cruise speed or configuration.
When ever I have been there poking my nose in to see if I can, I have been way slow lots of flaps(not real sure how much as depended on the aircraft) and usually a bit of power.
When there you are locked and loaded to turn!!
Most times when you decide to turn around you have to do it now!!
When you crank it around I hope you did not wait until you can't drop a wig enough to turn??
If you did and you are under an overcast you just became a statistic or a rescue!!
If you shove the rudder in all the way as you hit the stops with the ailerons and the throttle, it should take just a couple of seconds to be turned around, Yes you pulled back on the Stick or Yoke a whole bunch,for about 1/3 of you turn and then let the pressure off to finish the turn and drop the nose to keep flying. Down hill and P factor will all be in your favor.
When you get done you figure WOW I am Fin lucky to be alive and maybe I shooooooooould not go this far next time!!!
A few of those, a little luck and a few years and then you will find that you are not doing them near as much as you used to!!(if at all) If not you are usually DEAD!!
Some times when you find your self in a position like this it all comes down to lots of luck, reflexes, and a damn good maintenance program on your machine.
If you were smart and did everything by the book you will never have to use it!!
But at 500-1000 hrs we are all bullet proof and know it all, RIGHT!!
But how many of us are like that that fly the BC and Canyons?
JMHO FWIW $.00

I don't recall the usual books on Mountain Flying (eg Sparky Imeson), describing a canyon turn.

I got my PPL in British Columbia and the mountain check out included a canyon turn, but I remain cautious.

Using a Super Cub with a reasonable safety margin on the gust/load envelope, suggests that a 2 G turn at 75-80mph gives you reasonable safety margins (1.2x +) The no wind radius of this turn is approximately 65 metres.

Pulling 3 G (just over 70 degrees bank), and a reduced safety margin of 1.1 x Vs3g gives a speed of 85mph, the no wind radius reduces to less than 50 metres.

Conversely a slower speed and reduced angle of bank, eg 70mph and 45 degrees, results in a larger radius - 90metres.

While a 'tame' stall turn does allow unloading some G in the turn, the initial pull up needs careful application, and there is an assumption that you have speed in the bank - typically a full stall turn you are pulling 3-4 G on entry, with full power (not reduced by high DA), or you will reverse direction at a lower altitude than entry (not the object of the exercise in a canyon).

A gentle entry, say a 2 g pull up, is not going to put you into a position to reverse at close to zero g ( and therefore close to zero Vs), and do you really want to engage in semi aerobatics without a defined horizon?

In short obey the leave yourself an out and don't go beyond the point of no return advice.

How do I hydroplaning during canyon turn?

Kinda what I was thinkin'

Gump

Lol!

CamTom12 wrote:Flaps 10 creates more additional lift than it does induced drag. Flaps 20 creates close to equal additional lift as it does additional induced drag. Flap settings above this typically create more drag than lift. In a steep turn you're raising your stall speed because of the additional wing loading required to maintain vertical lift equal to weight.

You'd theoretically want flaps 20 to maximize additional lift while minimizing additional drag. It'll give you more excess power which you can then use to help maintain your altitude.

That's not discrediting anyone else's technique, just a description of my understanding of the aerodynamics involved in the flaps/power/constant altitude turn method.

I do think both have a place and a time when they're valuable.

You're confusing induced drag with parasite drag. Induced drag is by definition, the drag produced by the process of creating lift..... If you create more lift, you create more induced drag. That's why the back side of the curve goes waaaaay high in drag....induced drag.

But, your basic premise is pretty accurate: The difference is that as you go past about 25 degrees of flap or so in Cessnas, the PARASITE drag of those big barn doors starts to increase substantially. Now you've got both induced drag high, due to slow speed and lots of lift, plus you're creating a lot of parasitic drag with lots of flap hanging out there.

Semantics in practice...drag is drag

MTV

mtv wrote:

CamTom12 wrote:Flaps 10 creates more additional lift than it does induced drag. Flaps 20 creates close to equal additional lift as it does additional induced drag. Flap settings above this typically create more drag than lift. In a steep turn you're raising your stall speed because of the additional wing loading required to maintain vertical lift equal to weight.

You'd theoretically want flaps 20 to maximize additional lift while minimizing additional drag. It'll give you more excess power which you can then use to help maintain your altitude.

That's not discrediting anyone else's technique, just a description of my understanding of the aerodynamics involved in the flaps/power/constant altitude turn method.

I do think both have a place and a time when they're valuable.

You're confusing induced drag with parasite drag. Induced drag is by definition, the drag produced by the process of creating lift..... If you create more lift, you create more induced drag. That's why the back side of the curve goes waaaaay high in drag....induced drag.

But, your basic premise is pretty accurate: The difference is that as you go past about 25 degrees of flap or so in Cessnas, the PARASITE drag of those big barn doors starts to increase substantially. Now you've got both parasite drag high, due to slow speed and lots of lift, plus you're creating a lot of parasitic drag with lots of flap hanging out there.

Semantics in practice...drag is drag

MTV

Nope, you're right! Poorly worded on my part. Thanks for the correction!