Low altitude steep descending turns...

With all due respect, "energy management" isn't a required concept or even necessarily helpful. I've never thought in those terms and have no trouble, so neither need the OP. Thinking in terms of angle of attack and stick position is more helpful, IMO, because it gives a more accurate picture of the airplane's relationship to the stall, which is where you want to be at or near the landing point. Thinking only in terms of "energy" is much too simplistic--no backside of the power curve in that view, no best glide speed or minimum sink speed either. Everything coming down to just inertia leaves too much out.

dtuuri
 
I was under the impression that the horizontal component of lift is what causes an airplane to turn. :)
 
Lachlan said:
I was under the impression that the horizontal component of lift is what causes an airplane to turn. :)
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Not always true. In a forward slip, your horizontal lift component is countered by horizontal drag, resulting in a straight flight.
 
yetti said:
my instructor said "no more than normal rate turns in the pattern" I think it is a good rule to live by
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Good advice for student pilots...but not necessarily a rule to be rigidly adhered to as you gain experience.

Bob Gardner
 
RotorDude said:
I think the direct effect is roll, which could indirectly lead to a turn.
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Are you referring to torque effect (left bank vs right bank) versus the spiral slipstream, or gyroscopic precession? Sheer torque will certainly induce roll. Good times, good times...
 
Lachlan said:
So you're saying the rudder causes the turn? ;)
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No, I didn't say that, and it doesn't, at least not directly.

Lachlan said:
Are you referring to torque effect (left bank vs right bank) versus the spiral slipstream, or gyroscopic precession? Sheer torque will certainly induce roll. Good times, good times...
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Yes, you are right, I was referring to torque, not P-factor.
The former induces roll, the latter yaw. Neither one will turn the plane directly, but could do so indirectly.
 
2Airtime2 said:
...

When turning in the pattern, usually to final, sometimes the wind is such that I want/need to turn steeper. When around 75 kts how close are you getting to a stall condition at 30 degrees, at 45 degrees, at 60 degrees?

Am I correct that the slower you are going and the steeper you turn the higher the stall speed (plane stalls more easily) ?

Someone tell the difference in stall speed in the above scenarios when descending vs. holding altitude. I think if you are turning steep and descending the stall speed is lower (safer) than if you were holding altitude. Is that correct?

Which has a greater angle of attack? Steep altitude holding turns or steep descending turns?
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Steep turns in the pattern are not the way to adjust for winds. To answer your questions read the poh for the aircraft you fly and ask your instructor to explain what is unclear. He's paid to instruct. Ask him the difference between an accelerated stall and one that is not. You don't seem to be very far along if you can't answer these questions and if you were to roll into a steep turn to avoid overshooting final on your checkride because of a tailwind on baseleg, you'd be looking at a retake in your future. I've read a lot of bs on forums as well as some good info--the difficulty is knowing which is which.
 
denverpilot said:
Nice save from a dumb statement.
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In the pattern (except those few places where special maneuvers are approved) a 30° maximum bank is certainly the mark of a good pilot. It takes one to compensate for the wind without excessive banking. Not a dumb statement at all, but it was a good comeback if I don't say so myself. :)

dtuuri
 
dtuuri said:
In the pattern (except those few places where special maneuvers are approved) a 30° maximum bank is certainly the mark of a good pilot. It takes one to compensate for the wind without excessive banking. Not a dumb statement at all, but it was a good comeback if I don't say so myself. :)



dtuuri
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Overheads happen nearly every day "in the pattern" at my home field. Keep back-pedaling. You'll get your statement accurate if you keep adding qualifiers.
 
Witmo said:
Steep turns in the pattern are not the way to adjust for winds. To answer your questions read the poh for the aircraft you fly and ask your instructor to explain what is unclear. He's paid to instruct. Ask him the difference between an accelerated stall and one that is not. You don't seem to be very far along if you can't answer these questions and if you were to roll into a steep turn to avoid overshooting final on your checkride because of a tailwind on baseleg, you'd be looking at a retake in your future. I've read a lot of bs on forums as well as some good info--the difficulty is knowing which is which.
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I used the wind as an example. I made that up. The basis for my question is to learn what the plane is capable of doing safely (if ever need be).

dtuuri said:
I didn't. A good pilot can do anything the plane is capable of. A better pilot knows when not to.

dtuuri
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I'd like to be the better pilot. Wouldn't I need to know what the plane is and is not capable of so I know what not to do?
 
dtuuri said:
Canadians believe the angle of attack increases in a descending turn and vice-versa in a climb. In the US, we don't.
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Better go read those things again and understand.

The angle of attack increases in any turn. It has to, to counter the extra load factor. It does NOT decrease in a climbing turn. AOA is entirely dependent on load factor and airspeed.

The angle of attack in a descending turn increases more on the inside wing than on the outside wing. This is due to the steeper helix being described by the inside wing. It's not a large difference, but it's there, and if the ball is centered, that inside wing will stall a hair before the outside wing and it will roll into a spin. If we add bit of rudder to tighten the turn we get a skid, the AoA differential gets even larger, and we have the classic base-to-final stall-spin scenario.

In a climbing turn, the outside wing is at a higher AoA and will stall first.

In Canada we teach full stalls and spins and their recoveries, and we're familiar with what can happen when we do stupid stuff.

Here's another Canadian belief: American air is thin and very hostile so that stalls automatically result in unrecoverable spins and fatal crashes, so Americans don't dare do such stuff.
 
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2Airtime2 said:
I'd like to be the better pilot. Wouldn't I need to know what the plane is and is not capable of so I know what not to do?
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Of course, so now you have a license to fly under bridges and anything else you can imagine, right? Nope. In training we do some things to build experience, like slipping all the way down final or side slipping from one side of the runway to the other and back without changing heading, but there's no normal purpose for it. That's why we do turns around a point and steep power turns--to build experience. During pattern work, the lesson to learn is to keep the ball centered and bank as needed--not to skid around in a shallow bank which could end in a cross-controlled stall. The steeper you need to bank, the worse your planning was. After awhile you won't need to go beyond 30° and if you do it should send up a mighty big red flag alert to be coordinated and consider going around.

dtuuri
 
Dan Thomas said:
Better go read those things again and understand.

The angle of attack increases in any turn. It has to, to counter the extra load factor. It does NOT decrease in a climbing turn. AOA is entirely dependent on load factor and airspeed.

The angle of attack in a descending turn increases more on the inside wing than on the outside wing. This is due to the steeper helix being described by the inside wing. It's not a large difference, but it's there, and if the ball is centered, that inside wing will stall a hair before the outside wing and it will roll into a spin. If we add bit of rudder to tighten the turn we get a skid, the AoA differential gets even larger, and we have the classic base-to-final stall-spin scenario.

In a climbing turn, the outside wing is at a higher AoA and will stall first.

In Canada we teach full stalls and spins and their recoveries, and we're familiar with what can happen when we do stupid stuff.

Here's another Canadian belief: American air is thin and very hostile so that stalls automatically result in unrecoverable spins and fatal crashes, so Americans don't dare do such stuff.
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Just don't mention the way Canadians enter the pattern at uncontrolled airports.

:popcorn:
 
Dan Thomas said:
The angle of attack increases in any turn. It has to, to counter the extra load factor. It does NOT decrease in a climbing turn. ...

In a climbing turn, the outside wing is at a higher AoA and will stall first.
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If the bank is the same then the left wing (left example bank) went from a higher AoA to a lower AoA as the plane went from a descent to a climb, no? Forgive me if I'm having trouble with Canadian aerodynamics, but this is all new to me. If the FAA covers it--I missed it. Don't know how I survived since 1963 not knowing about it either.

dtuuri
 
dtuuri said:
In training we do some things to build experience, like slipping all the way down final or side slipping from one side of the runway to the other and back without changing heading, but there's no normal purpose for it.
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I'll be damned. I missed the memo where we banned crosswinds. Nature must be ****ed.
 
Dude, long F'ing story short, know you're aircrafts capabilities, more over know your own, and do what's safe and prudent.
 
denverpilot said:
I'll be damned. I missed the memo where we banned crosswinds. Nature must be ****ed.
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Well, speaking of air, I have to go air up a couple of tires. Try not to confuse the OP while I'm away.

dtuuri
 
dtuuri said:
Well, speaking of air, I have to go air up a couple of tires. Try not to confuse the OP while I'm away.
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No worries, we leave that stuff up to you. ;)

I mean heck, we have every military fighter pilot flying their standard patterns defined as not good pilots by you, and everyone who's ever landed in a crosswind doing things nobody should ever do after training...

Just in this one thread alone. A two-fer!

Who'd need more confusion than that?
 
Dan Thomas said:
Better go read those things again and understand.

The angle of attack increases in any turn. It has to, to counter the extra load factor. It does NOT decrease in a climbing turn. AOA is entirely dependent on load factor and airspeed.

The angle of attack in a descending turn increases more on the inside wing than on the outside wing. This is due to the steeper helix being described by the inside wing. It's not a large difference, but it's there, and if the ball is centered, that inside wing will stall a hair before the outside wing and it will roll into a spin. If we add bit of rudder to tighten the turn we get a skid, the AoA differential gets even larger, and we have the classic base-to-final stall-spin scenario.

In a climbing turn, the outside wing is at a higher AoA and will stall first.

In Canada we teach full stalls and spins and their recoveries, and we're familiar with what can happen when we do stupid stuff.

Here's another Canadian belief: American air is thin and very hostile so that stalls automatically result in unrecoverable spins and fatal crashes, so Americans don't dare do such stuff.
Click to expand...

What about those Canadian airplanes that have a lot of dihedral, ay? And isn't a Canadian turn called a banque? I think the Coriolis Effect is less pronounced in Canada because they're closer to the other side of the pole, so that definitely changes things. They're not allowed to carry guns, so that alone decreases the Angle of Attack.
 
denverpilot said:
No worries, we leave that stuff up to you. ;)

I mean heck, we have every military fighter pilot flying their standard patterns defined as not good pilots by you, and everyone who's ever landed in a crosswind doing things nobody should ever do after training...

Just in this one thread alone. A two-fer!

Who'd need more confusion than that?
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>30 degree banks in the pattern is the mark of a bad pilot, and energy management is useless.

The blue board can be so entertaining. :D
 
Herve Marchadier said:
>30 degree banks in the pattern is the mark of a bad pilot, and energy management is useless.



The blue board can be so entertaining. :D
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By the way, you quoted the wrong person. Just a technical nit. I got an alert that I had been quoted. You quoted dturri's quote where I quoted him. Happens.
 
denverpilot said:
By the way, you quoted the wrong person. Just a technical nit. I got an alert that I had been quoted. You quoted dturri's quote where I quoted him. Happens.
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I quoted you so that you'd see the alert. I that's how I roll.
 
denverpilot said:
I mean heck, we have every military fighter pilot flying their standard patterns defined as not good pilots by you, and everyone who's ever landed in a crosswind doing things nobody should ever do after training...

Just in this one thread alone. A two-fer!

Who'd need more confusion than that?
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Not going to dignify that with a rebuttal, so I'll just repeat myself for the OP. Truer words were never spoken:

dtuuri said:
Ok, first of all you really never need to bank more than 30° in the pattern. It's a good rule to follow and the mark of a good pilot.

Secondly, airplanes turn because of the back pressure (tail down force). That's what increases the angle of attack and causes curving flight. Straight and level is really a special case situation--there's a tail down force and angle of attack, but no turn results because gravity is constantly canceling the inherent curve the plane is trying to make (a loop). If there were no gravity during straight flight, there'd be no need for back pressure (tail down force), no angle of attack and no curving force. To curve, you need back pressure more than enough to counter gravity.

Canadians believe the angle of attack increases in a descending turn and vice-versa in a climb. In the US, we don't.

Stall speed increases in steeper turns because in order to achieve the tighter turn radius you have to increase the angle of attack. If you lessen the angle (of attack) to the point of zero 'g'--you won't turn anymore, thus defeating the purpose.

dtuuri
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Keep doubling down. Maybe someone will believe your statement about "the mark of a good pilot".

I certainly wouldn't want to get any of your "dignity" on me, so I appreciate the courtesy.

If you change your mind, let us know so I can grab the hip waders and hook up the garden hose.
 
denverpilot said:
Keep doubling down. Maybe someone will believe your statement about "the mark of a good pilot".
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Aha! You aren't good 'nuff to do it, are ya! Why else are you so defensive? Always turning final too late aren't ya! Don't be like this, OP. Just keep asking yourself, "Am I too high or too low?" Then make an adjustment. Then repeat right away. That's how it's done. Constant reappraisal, make a "guess" and make an adjustment. If you guess wrong, you'll know it in five seconds, then do the opposite.

dtuuri.
 
FastEddieB said:
I think you'd have to add the word "level" between "any" and "turn" for that to be anywhere close to true.
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A straight-line descent is 1G. A straight-line climb is 1G. Adding a turn to either adds load factor and therefore AoA. The only time you might have less in a climbing or descending tuirn is while the climb is levelling off or the descent is steepening.
 
Dan Thomas said:
A straight-line descent is 1G. A straight-line climb is 1G. Adding a turn to either adds load factor and therefore AoA. The only time you might have less in a climbing or descending tuirn is while the climb is levelling off or the descent is steepening.
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Not sure that's right.

If I initiate a turn using only aileron and a tad of rudder, without pulling back on the stick, the plane will descend and I don't believe AOA will increase.

It's the holding altitude with the elevator that increases the AOA, not the turn itself.

I think. Though anything involving aerodynamics can get complicated very quickly, and when math comes in I'm pretty well cooked.

In any case I remember doing wingovers at well over 60º bank and very low speeds in a Citabria without stalling. I think that's only because no attempt was made to hold altitude.
 
FastEddieB said:
In any case I remember doing wingovers at well over 60º bank and very low speeds in a Citabria without stalling.
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Ah, but you were real close. Coming down the back side of a real steep lazy eight is right on the verge of a stall (just past the apogee). Even though the nose is below the horizon you can feel it burble.

dtuuri
 
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