Downwind turn

Silvaire

Silvaire

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Silvaire
Why does this meme exist in our pilot's dictionary? We know that once airborne the only wind effect on our aircraft (outside of sudden gusts, shifts or shears - aka turbulence) is our path across the now disconnected ground. Yet it keeps coming up time and again in discussions and it keeps killing people. What often is missing in those discussions is the fact that it is an illusion rater than a physical phenomenon. It only happens when you are close to the ground and even then, it won't happen if you don't look at the ground. When you start using the ground as a reference for your heading (where the nose is pointed) that's where the trouble begins.

But we were all taught this in the beginning right? That's what ground reference maneuver practice was all about as well as basic pattern work and crosswind landings.

It seems this "illusion" is very powerful. I learned a long time ago how easy it is to get uncoordinated when focused on the ground and low yet it still happens.

What do you guys think?
 
It's a phenomenon that just needed a name.
 
Silvaire said:
Why does this meme exist in our pilot's dictionary? We know that once airborne the only wind effect on our aircraft (outside of sudden gusts, shifts or shears - aka turbulence) is our path across the now disconnected ground. Yet it keeps coming up time and again in discussions and it keeps killing people. What often is missing in those discussions is the fact that it is an illusion rater than a physical phenomenon. It only happens when you are close to the ground and even then, it won't happen if you don't look at the ground. When you start using the ground as a reference for your heading (where the nose is pointed) that's where the trouble begins.

But we were all taught this in the beginning right? That's what ground reference maneuver practice was all about as well as basic pattern work and crosswind landings.

It seems this "illusion" is very powerful. I learned a long time ago how easy it is to get uncoordinated when focused on the ground and low yet it still happens.

What do you guys think?
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This stays alive for the same reason the airplane on a treadmill question does. Not everyone who flies actually understands how flying works.
 
The best flying book I’ve ever read is Contact Flying by Jim Dulin. He’s a former Viet Nam Cobra pilot and more recently an Ag pilot and Ag/Bush flying flight instructor. He has lots to offer but in general states that below 500’ AGL, instruments are unnecessary and dangerous. The whole idea of contact flying is by eyes and feel. It makes perfect sense to me because that’s how I’ve always flown. I don’t care how an airplane turns at 5000’ AGL. I care how it turns close to the ground in a tight valley with a small strip cut into tall trees. Ag pilots care because they operate close to the ground within boundaries while on the clock. If you don’t think a downwind turn needs your full attention? You probably don’t fly in places where it matters.
 
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Stewartb said:
If you don’t think a downwind turn needs your full attention? You probably don’t fly in places where it matters.
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Which pattern turns do not require your full attention? The question is whether an airplane is more likely to stall when turning away from the wind. It's not.
 
That’s YOUR interpretation. We’re piloting airplanes in a moving environment to fixed facilities. Draw a box and maintain your ground track in different winds. It has nothing to do with the theory of flight, it has to do with the ground. Turning downwind requires more space. Make that turn in a defined, restricted space and you may understand.
 
Stewartb said:
That’s YOUR interpretation. We’re piloting airplanes in a moving environment to fixed facilities. Draw a box and maintain your ground track in different winds. It has nothing to do with the theory of flight, it has to do with the ground. Turning downwind requires more space. Make that turn in a defined, restricted space and you may understand.
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That's not the basis for the downwind turn debate that's been raging on the Internet since IRC days.
 
Again, your interpretation. I’ve had the discussion a thousand times. Nothing new. Maybe we should talk about driving a boat in a current and turning to avoid hazards? Is that easier to comprehend? Probably not for guys who’ve never done it.
 
Here are a bunch of similar misconceptions I threw together a while back, including “The Dreaded Downwind Turn”.

www.pilotsofamerica.com

"Stick and Rudder Moments" - redux

In another thread a pilot opined that wind made a difference in cooling in a Seneca. I searched every which way and cannot find my original post on "Stick and Rudder Moments". So, I thought I would amend it (example #5) with the current example and re-post it: As background, Stick and...
www.pilotsofamerica.com www.pilotsofamerica.com
 
Lindberg said:
That's not the basis for the downwind turn debate that's been raging on the Internet since IRC days.
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Actually, it is The basis for the debate…pilots can’t clearly separate the aerodynamic issues from the illusion/space requirements, and use one in a discussion about the other, creating confusion.

it’s similar to the confusion that results when pilots troubleshoot a Crossfeed malfunction using the word “transfer,” and go Into the wrong checklist. It just doesn’t make sense.
 
Here's the real controversy...



I love ketchup with my spaghetti and I put ketchup in my salad......
 
Comes from the RC crowd, and many pilots who first learned to fly RC still believe it's a thing. Same as "tip stall". RC BS.
 
RoscoeT said:
Comes from the RC crowd, and many pilots who first learned to fly RC still believe it's a thing. Same as "tip stall". RC BS.
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Exactly. Those RC guys are full of misconceptions. They think that the downwind turn is lethal because they see the airplane speed up so they reduce the power and keep the nose up, and down it comes. And they think that the wings are fine until the tips stall, which begs the question as to why we bother with the rest of the wing and its weight and drag. They just don't understand that many airplanes will drop a wing, but its tip is still flying, provable by continued aileron response.

Our Canadian Flight Instructor syllabus has this in it, and I imagine the US has the same:

Exercise 20 - Illusions Created by Drift - Low Flying​

Objective​

To teach the student:

(1) To cope with the illusions created by drift by maintaining co-ordinated flight in turns.

(2) How to maintain a desired track by compensating for the effects of drift while manoeuvring at low level.

Motivation​

As required.

Essential Background Knowledge​

(1) Explain:

  1. Illusions and effects of flight at low level in a strong wind:
  2. into-wind - reduced ground speed produces an illusion of reduced airspeed;
  3. downwind - increased ground speed produces an illusion of increased airspeed;
  4. when turning from downwind an illusion of a skid outwards results;
  5. when turning from into-wind an illusion of a slip inwards results.
B. Situations where illusions can produce potentially dangerous flight conditions, e.g., low level circuit and approach while operating under conditions of low ceilings, turns at low level associated with high winds, etc.;

The false "downwind turn" phenomenon is easily disproven under the hood. On a day with a strong wind and little turbulence, and with an observer pilot, of course, put the hood on and then do a continuous 30 or 40° banked turn, and see what the airspeed indicator does. See if there's anything you feel that tells you whether you are entering a headwind or tailwind or crosswind. You'll find nothing.
 
flyingron said:
But how do you feel about pineapple on your pizza?
Ketchup on your hot dog?
Anchovies in your greek salad?
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Pineappleon pizza....ok as a once-in-a-while thing
Ketchup on a hit dog...plain hot dogs for me but my wife is mustard and relish
Anchovies? YUCK

Now, what was the original topic?
 
Any ag pilots here? Energy management is vital in that profession. How to manage 180° turns upwind and downwind is different. Especially with power lines or wind breaks on the field edges. Can you nay-sayers agree with that, or do you believe it doesn’t matter? That’s an honest question.

Maybe more in your wheelhouse, imagine an approach to a runway in a crosswind that’s at your limit. You decide to make a pass at it. Do you prefer the base leg into the wind or wind on your tail? Why?
 
Stewartb said:
Any ag pilots here? Energy management is vital in that profession. How to manage 180° turns upwind and downwind is different. Especially with power lines or wind breaks on the field edges. Can you nay-sayers agree with that, or do you believe it doesn’t matter? That’s an honest question.

Maybe more in your wheelhouse, imagine an approach to a runway in a crosswind that’s at your limit. You decide to make a pass at it. Do you prefer the base leg into the wind or wind on your tail? Why?
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First example: one must ”manage” those turns because they’re essentially a ground reference maneuver.

Second example: the advantage of a base leg into the wind is to buy more time. A base leg with a tailwind results in a very fast base leg, and a strong wind can easily drift the plane past final, tempting pilots to skid the nose around with rudder, with sometimes dire results.

No one is denying a moving air mass affects how a plane must maneuver when using ground references. The question is does it affect the plane’s stall speed. It doesn’t.
 
Stewartb said:
How to manage 180° turns upwind and downwind is different. Especially with power lines or wind breaks on the field edges. Can you nay-sayers agree with that, or do you believe it doesn’t matter?
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Aerodynamically, it does not matter. To the airplane, it does not matter.
 
StewartB is making the point that the wind can carry you into the wires or the trees or a rock face if you think that the wind doesn't affect your ground track. It does that, alright. In a canyon with a crosswind across it, a turn from the upwind side to the downwind side could carry you into the rocks. A takeoff with a tailwind might flatten your climb angle enough to get you into the wires or trees. Such a takeoff will already have a longer ground roll, too. In a wind, cropspray pilots would have to be making adjustments all the time for stuff like this. They're down among the wires and trees and sometimes terrain. But since spray operations risk wind drift of the spray onto neighboring crops, they prefer windless days, which is why they often fly at dawn and stop once the wind picks up, and go back to work in the evening after it has died down.

Floatplane pilots have the most fun. They have to contend with river or tidal currents AND the wind all at the same time.
 
Dan Thomas said:
StewartB is making the point that the wind can carry you into the wires or the trees or a rock face if you think that the wind doesn't affect your ground track.
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Literally no one has ever said that. In the history of never has anyone said the wind doesn't affect your ground track. That's not what the Downwind Turn debate is about. Although I agree that if someone said that, it would be dumb.
 
How do you know what others are thinking? If somebody out there doesn’t recognize that ground reference plays a part, why not explain it to them?

Imagine a big, smooth lake. There’s a ripple from the wind. A floatplane is practicing step turns. Does the turn take more space going into the wind or down wind? The lake isn’t moving. Apparently the airplane doesn’t know the wind is blowing. What forces are affecting the turns? And Dan’s correct. Fly floats on flowing water and the wind can make things very interesting.

Do you guys have a personal limit on wind velocity for taking off or landing downwind? What’s your limit? Why?
 
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Half Fast said:
No, the real controversy is pouring A1 onto a perfectly good steak. Why do people do that?
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A1. The American fake version of HP Sauce, popular in Britain and Canada. Dark brown like A1, but definitely different. Good on meats, eggs.

1690325173655.png
 
Half Fast said:
No, the real controversy is pouring A1 onto a perfectly good steak. Why do people do that?
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Two dogs talking: "Of course I put horseradish on dog food. You put steak sauce on steak, don't you?"

Nauga,
when in Rome...
 
flyingron said:
But how do you feel about pineapple on your pizza?
Ketchup on your hot dog?
Anchovies in your greek salad?
Click to expand...
Try anything once. Tried all of the above before and would say:
- Not so much pineapple on pizza
- Ketchup is for fries.
- Anchovies belong in a greek salad!
 
Stewartb said:
Do you guys have a personal limit on wind velocity for taking off or landing downwind? What’s your limit? Why?
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Doesn't look like @FastEddieB above approves of downwind departures or landings, unless I interpreted incorrectly... Personally I believe there are a number of reasons to do it. When a runway is sloped, does one land downhill and upwind or uphill downwind (and what is the wind/slope decision point)? At my home airport, night ops are one way in and one way out; if winds are not favorable for your direction do you just not go? Say the sun is setting directly in front of the upwind runway and making visibility difficult in that direction; do you still land that direction or choose a downwind landing in the opposite direction?

What is my limit? I don't have a set limit. It would vary based on the available runway, alternatives, situations such as described above, etc.
 
Stewartb said:
Any ag pilots here? Energy management is vital in that profession. How to manage 180° turns upwind and downwind is different. Especially with power lines or wind breaks on the field edges. Can you nay-sayers agree with that, or do you believe it doesn’t matter? That’s an honest question.

Maybe more in your wheelhouse, imagine an approach to a runway in a crosswind that’s at your limit. You decide to make a pass at it. Do you prefer the base leg into the wind or wind on your tail? Why?
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Yes.

You are wasting your time.
 
With all due respect to Mr. Lowery, this slackening wind idea is bunk. The wind is not changing regardless of which way the airplane is going
 
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