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9 hours ago, facthunter said:

What was the turning DOWNWIND about?.  Nev

I think he is just thinking aloud. He did mention crosswind and downwind when he spoke about situational awareness.  He must be doing something right. 31000 hours as an Ag pilot and airshow pilot is a pretty good resume.

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I also found that Air Tractor video very helpful; it was clearer than most I've seen on the complex of forces acting on a turning aircraft.

 

I think Nev's problem was with the guy uttering the word "downwind" while talking turns, seeing it, I guess, as adding to the (much discussed) myth of the downwind turn.

 

Like Brendan, though, I doubt that this savvy ag/airshow guy simply buys-into the widely held myth and is, therefore, 'wrong'.

 

The video was, after all, an ad hoc interview and he didn't really seem to finish that thought. 

 

If he had, he may have complicated the matter with the 'wind-shear' exception and/or dangerous visual illusions.  Who knows?

 

In any case, for anyone interested, here's one example of the topic debated online (with some relevant bits extracted).

 

(There are many discussions of the same thing on here, as well)

 

 

 

AVIATION.STACKEXCHANGE.COM

As we know it, aircraft are extremely sensitive to gust during its final landing stage. They can lose airspeed if the wind changes to tail, ad thus loose lift or need to adjust their thrust in orde...

 

"The myth of the downwind turn

 

... As you stated the plane is moving along with the airmass. So, for the plane, aerodynamically there is no head-, side-, or downwind.

Only us on the ground can feel it, as we are locked into to the coordinate system of the earth with our feet.

The airplane is locked into the coordinate system of the airmass, and as long as the airmass itself does not experience acceleration, the airplane flying in it can turn in whichever way, and it will not notice any change in the wind direction. The direction of the wind is locked into the coordinate system of the earth, so in your example there is no change in wind direction."   Jpe61

 

"Windshear (a sudden and/or drastic change of wind velocity) will affect airspeed momentarily until the plane’s momentum is overcome by the aerodynamic forces acting on it. This will be most apparent as turbulence or loss of performance. It is also most apparent during slow flight due to being so close to your performance envelope edge. The sudden gain then loss of altitude when flying through a microburst is a good example of that.  

... During landing, your slow airspeed and proximity to the ground combined with the vertical component of your momentum makes any loss of performance dangerous. It could lead to a sudden increase in descent rate at the wrong moment or a stall if you are too slow. A change in wind velocity as little as 5-10 knots can have an effect on the plane. That’s why pilots are encouraged to add half of the gust factor (the difference between the steady wind and the peak wind) to their approach and landing speeds.

In your example, it looks like you are concentrating more on changes in relative wind velocity based on changes in aircraft heading instead of windshear. That is different. The aircraft’s airspeed will remain the same. There will be no loss of performance relative to the airmass because the aircraft is flying IN the airmass. The airplane does not care about its performance in relation to the ground unless it is on the ground."   DeanF

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That's a pretty good explanation.. Windshear is mostly a low level phenomenon and whatever cross wind you have will often diminish at flare height but the extent will vary. In x winds and gusts you carry a speed margin to cover the possibility of  airspeed reducing when it's already low.  Nev

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1 hour ago, facthunter said:

I don't care how many hours of "whatever" he HAS.. What he said is wrong.  Nev

I guess he knows nothing then. Sounded like he knew what he was talking about. Sorry nev. 

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You DO over react. Just "think" about it and do some research. Maybe start with what Garfly kindly posted, above.  Wrong concepts in this area are dangerous. Despite your obvious lack of faith in my ability I'll keep doing what I'm here for. Nev

Edited by facthunter
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I think turning down wind in ag ops has some things to think about. The aircraft is making a climbing turn from the surface and can be seeing an increasing tail wind due wind gradient. Also remember they are turning back to the next pass in a racetrack pattern so more bank and yank may be required compared to turning up wind. 

 

I agree the down wind turn is a myth if you are not concerned with the actual location of the aircraft at the completion of the turn.

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Getting above 200 ft would be the exception. when spreading . That's where the shear is likely to be and there's topographical eddies to consider as well. IF you pull a plane straight off the ground and at the same time turn into wind you will get a short period of faster climb rate but you have used the grip on the ground to help you. At height you don't have that. You are turning in a parcel of air.  Nev

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3 hours ago, facthunter said:

You DO over react. Just "think" about it and do some research. Maybe start with what Garfly kindly posted, above.  Wrong concepts in this area are dangerous. Despite your obvious lack of faith in my ability I'll keep doing what I'm here for. Nev

 don't pull the poor nev card out when someone doesn't agree with you. . Wouldn't a spraying pattern be like a training circuit. We call crosswind and downwind doing that. I think you are reading to much into what he said.

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 . I personally couldn't give a tuppeny for what you think of Me. I just want to make sure everyone gets the Facts straight. because IF they don't they might find out the hard way. This exact subject was gone through  years ago on this  forum. I've lost over 7 good friends in aircraft accidents many due to not knowing enough that should have been made clear.. Often they take others with them. It's all preventable.  Nev

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3 hours ago, facthunter said:

 . I personally couldn't give a tuppeny for what you think of Me. I just want to make sure everyone gets the Facts straight. because IF they don't they might find out the hard way. This exact subject was gone through  years ago on this  forum. I've lost over 7 good friends in aircraft accidents many due to not knowing enough that should have been made clear.. Often they take others with them. It's all preventable.  Nev

Stop acting like a baby. You know I listen to your advice and aviation experience. I just don't agree with you this time.

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Its an ok video; too much talking, watched it a few years ago... the final advice about setting wings level come back for another go when you got your composure back was probably the key take away here. There was some superficial mention of stall and yaw, and loading the wing up. "Risk has no memory" is another great take away. Also, suggestion to go get more training if you feel uncomfortable is another key take away.

 

Unfortunately no mention is made regarding knowing where the stick stall position is; which is the single most critical must have for any pilot wanting to avoid spins in any fixed wing aircraft. If the video opened with that statement it would probably actually make an impact and save lives.

 

I will disagree on the premise toward smooth and steady flying; balanced flying would probably be a better concept to present. I get where he is coming from when he says "smooth and steady" however it is misleading and totally incorrect. Any slow uncoordinated skid or slip turn can feel joyfully smooth and steady right up to the second the tin can suddenly flips over and heads toward the dirt.

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An instructor who supported me a lot in my early training told me to always be gentle with control movements. Over a period of time I had to get that idea OUT of my head. You sometimes need everything in the corner and full power quickly. Stick stall position is a good concept. The actual pitch attitude means nothing to the stalling situation. Its WING AoA. What decides THAT? The elevators moved by you, the Pilot..  While the idea of gliding to the field is a common AIM using the throttle as another control is a good way of arriving exactly at the Place, and speed and height you want to be, particularly in gusty conditions or short strips.  You are also more ready to initiate a go around. We can anticipate MORE wind changes  with extremes of weather. Watch for dust devils (without the DUST sometimes.) Nev

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23 hours ago, BrendAn said:

Stop acting like a baby. You know I listen to your advice and aviation experience. I just don't agree with you this time.

I  apologise to nev for this comment and the earlier one. After reading them again I realise how disrespectful they were.  

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