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Coping with significant crosswind


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I got rid of the beard. I wanted to be different. ( OFF TOPIC) ..Nev

....perhaps you wanted to be different Nev but your avatar is still very "standard". You'll need to work on it 010_chuffed.gif.c2575b31dcd1e7cce10574d86ccb2d9d.gif

 

 

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Jim Davis had a an article in Australian Flying a while back which makes entertaining reading atwww.australianflying.com.au/news/dragons-of-the-downwind-turn

The problem advanced by Merv attracts strong comments from supporters of each of the theories but it seems to me if you are more or less stationary in a 50 knot headwind relative to the ground you are relying totally on the headwind for your airspeed. If you then turn crosswind, especially if you turn quickly, you have lost all airspeed except for whatever has been gained by accelerating under throttle which means overcoming inertia. That doesn't happen straight away.

 

No, no. no. Not this old hoary chestnut again!! Remember when the opposing protagonists were attempting to beat themselves into a pulp per medium of the AOPA magazine about a decade ago. Did any consensus emerge?

 

I have no desire to buy into this one. From my observations I have taken note that when observing the Ag pilots at work, the turns with downwind usually have a bit of airspeed on board, and at the end of the sequence when airspeed has been washed off is it co-incidence that they are then working back into wind? Though these days with GPS marking the Aggies peeling off proceedure turns have just about vanished. Poteroo, what sayeth thou?

 

Whilst most discussion on this topic is on the effect of wind in the horizontal plane, aerobatic pilots contend with it in the vertical plane. A loop into wind, especially in a lower powered aircraft or glider, benefits by rounding out the top of the loop. One learns very quickly that a half roll off the top is far more easily performed when you commence the half loop downwind.

 

Now that I have chucked in some tuppeny thoughts I shall retire, and keep my head down!!

 

 

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This is not a hoary old chestnut, it just exposes those who didn't study BAK as they should have before they flew solo.

 

It's wrong to perpetuate the confusion of new students when the answer is straightforward.

 

Jim Davis explained it well.

 

I think another understanding - "flying close to the ground is ground speed related in strong winds" would be helpful, so we understand that:

 

  • when flying downwind in a strong wind we are more likely to miss our normal turning points and pull on too much aileron and spin in instead of starting the turn earlier or just accepting that we screwed up and allowing the aircraft to turn safely before correcting our position.
     
     
  • hooning around low where there are trees, poles, aerials or other high features, in a high wind is likely to see us slipping or skidding into the object, or not being able to outclimb it.
     
     
  • Windshear at low levels is separate to our bubble of air, and can make us drop like a rock.
     
     

 

 

I would imagine that the comment about aerobatic pilots contending with this in the vertical plane also relates to ground speed in terms of them staying within their box, fixed above the ground,

 

 

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Yea tubz. Wouldn't say it's exposing anything other than the complexity of aerodynamics. We have so far had 2 atpl holders sitting in different sides of the fence, so it's hardly an obvious part of BAK being under taught. which by the way, there is no reqierment to pass before going solo. ;)

 

Cheers

 

 

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I wouldn't call this Basic Aeronautical Knowledge. Quite a few experienced pilots have difficulty with it. It's a conceptual thing. Like the one where you are landing on a conveyor belt. The answer is simple if you get the relevant factors applied right.

 

Illusions that may give you a difficult time when flying near the ground are a different thing and should be covered fully in the low flying training (when and If done) Interestingly even though I had it "low level"signed off in my log book and had taught it firstly as a GA instructor and later as a senior RAAus instructor. Mick POOLE would not put it on my endorsements on the certificate until I had some "reason" for it, like teaching mustering or something. I never understood that. Nev

 

 

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The two of you are right of course, it's not basic knowledge.

 

I wouldn't call it under teaching because BAK is mostly self study.

 

It may not be necessary to pass BAK before solo in RAA, and also GA, but I owe my life to studying it prior to about an hour and a half after second solo; without it I would have pulled back on the stick and spun in, hence my comment

 

This principle is not hard to learn if you are taught the ball or cube of air version, without the preamble of talking about how many argue against it etc.

 

2 atpl holders on different sides of the fence? Pfft! you should hear the dabate among the Captains of Airliners in Another place on the correct use of radio.

 

FH, I didn't mean to stray into genuine low level flying - that's a more complex subject, I was just thinking more about the show off take off with the immediate climbing turn.

 

Smart man that Mick Poole, although he may have got it wrong in your case.

 

 

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Turbo, You know me. I reckon we all need to get across what is happening, or likely to happen up there, so I like it all.

 

I reckon there are more or less three issues.

 

1 The flying in the airmass, which is a fact but a brainteaser. Doesn't cause a lot of grief in reality. Ball in centre.

 

2 The windshear in the air near the ground. ( lower layers, say ground to 60 feet). change of direction and speed. effects on control and performance.

 

3 Illusions of extra/less speed and turning radius/lead/lag time at circuit heights when manoeuvering with reference to a point on the ground.

 

The last one is often the one of more significance to safety . I think it can catch some experienced people.

 

Regarding the second one, I would never attempt a turn downwind immediately after lift off, but a turn into wind in the same circumstances gives quite a boost to the climb rate.. You're not supposed to turn before 500' anyhow so it's hypothetical isn't it? Not if you have just lost an engine. ( and it's the only one you have).. Nev

 

 

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They used to say that. They reckoned there was a shortage of Rat poison. The company Nurse went one better. Said with me they threw out the baby and kept the afterbirth. Nothing's sacred., but you can see why I'm uncomfortable with praise. ( on those thankfully rare ocasions) Nev

 

 

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A good read is John Freemans Flight at Lower Levels, and the sequel, Flight at Lower Levels - Safety in the Circuit. The effects of wind shear on a turning aircraft is very instructive. That's why older aggies,(with lower HP and power:weight), climbed to 50-100 ft, then executed the downwind procedure turn as the aircraft was levelled. We still teach the procedure turn, level at first, as it's a good co-ordination exercise and ensures that you can fly a track reversal accurately, regardless of the wind. Good if you want to relocate something seen while flying at any height.

 

happy days,

 

 

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.... Smart man that Mick Poole, although he may have got it wrong in your case.

No doubt, tubz, no doubt. But I did see him having trouble with a certain Cessna TD one day not that long ago

 

drive.gif.1181dd90fe7c8032bdf2550324f37d56.gif

 

kaz

 

 

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