wake turbulence FAA question confusion
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wake turbulence FAA question confusion
My ground kit has the following question & answer in it:
"When departing behind a heavy aircraft, the pilot [of the smaller aircraft] should avoid wake turbulence by maneuvering the aircraft...above and upwind from the heavy aircraft."
OK, the above part I understand, that is obvious since wake vortices sink behind the generating aircraft. But how could I possibly position myself UPWIND of a departing aircraft? He is going to take off INTO the wind, like I am, and therefore I will be taking off DOWNWIND from him, correct? If he and I stopped dead in our tracks in the sky, and he blew smoke out his window, it's going to blow DOWNwind to me.
Perhaps I am not understanding this question correctly?
This is an explanation to the answer I found online:
"The proper procedure for departing behind a large aircraft is to rotate prior to the large aircraft's rotation point, then fly above and upwind of the large aircraft. Since vortices sink and drift downwind this should keep you clear."
Again, how do I get upwind of the heavy aircraft, without overtaking it?
"When departing behind a heavy aircraft, the pilot [of the smaller aircraft] should avoid wake turbulence by maneuvering the aircraft...above and upwind from the heavy aircraft."
OK, the above part I understand, that is obvious since wake vortices sink behind the generating aircraft. But how could I possibly position myself UPWIND of a departing aircraft? He is going to take off INTO the wind, like I am, and therefore I will be taking off DOWNWIND from him, correct? If he and I stopped dead in our tracks in the sky, and he blew smoke out his window, it's going to blow DOWNwind to me.
Perhaps I am not understanding this question correctly?
This is an explanation to the answer I found online:
"The proper procedure for departing behind a large aircraft is to rotate prior to the large aircraft's rotation point, then fly above and upwind of the large aircraft. Since vortices sink and drift downwind this should keep you clear."
Again, how do I get upwind of the heavy aircraft, without overtaking it?
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The wind rarely blows exactly down the runway. If there is a crosswind, the wake turbulence will drift with it, therefore if you place yourself 'upwind' - into the crosswind - relative to the departing heavy's track, you increase your separation from the wake turbulence.
If you were to fly down crosswind, you might just run into the drifted vortex.
Make sense?
If you were to fly down crosswind, you might just run into the drifted vortex.
Make sense?
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Ah, OK, now that makes sense. If the wind IS down the runway, the question doesn't work (with the 3 multiple choice answers provided). But with a crosswind component, it makes sense. Thanks.
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I completely agree with the foregoing.
Add to that, that while fooling around with a buddy once, I deliberately entered his wake turbulance in cruise flight (both in 150's). It and it pretty well put me on my wingtip, despite all of my efforts to control. Do not blunder into wake turbulance! Learn where and when to expect it, and stay out.
Add to that, that while fooling around with a buddy once, I deliberately entered his wake turbulance in cruise flight (both in 150's). It and it pretty well put me on my wingtip, despite all of my efforts to control. Do not blunder into wake turbulance! Learn where and when to expect it, and stay out.
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The other thing to add here is that even though your take-off roll will typically be shorter than a "heavy", you probably will not be able to outclimb him in the long run.
So if you can make a turn into the crosswind straight after take-off, so much the better. After all, most heavies will remain on the extended centerline for a few miles before making their first turn.
So if you can make a turn into the crosswind straight after take-off, so much the better. After all, most heavies will remain on the extended centerline for a few miles before making their first turn.
Very much agree with the previous two replies.
There have been three wake turbulence accidents where I work. In each case it was in regard to a heavier departing a/c.
It is often difficult to predict where the vortices are/will be from a preceding departure. It is better to wait the 2/3/4 minutes than try to second guess them.
Avoiding landing vortices, however (in a headwind condition) is a piece of cake.
There have been three wake turbulence accidents where I work. In each case it was in regard to a heavier departing a/c.
It is often difficult to predict where the vortices are/will be from a preceding departure. It is better to wait the 2/3/4 minutes than try to second guess them.
Avoiding landing vortices, however (in a headwind condition) is a piece of cake.
