Nosedragger,
I hit send before I was done. Thanks for the very astute question.
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contactflying wrote:Nosedragger,
That is correct. By maintaining what appears to be a brisk walk, our airspeed will automatically be higher in a headwind and will automatically be lower in no wind and even lower yet in a tailwind.
If we are maintaining what appears to be a brisk walk in a 30 knot headwind, however, most pilots and all aircraft would want to take advantage of an even slower ground speed on touchdown. So we would use even a bit more elevator to slow both apparent rate and ground speed even more. Realize that the pitch attitude will still be less than in the no wind because the headwind is automatically slowing our ground speed. The airplane is feeling just fine with all that 30 knots extra kinetic energy of pressure airspeed over and under the wing so why not take advantage of the help?
There are some things we have to watch for, however, on this pleasantly slow and easy to control approach into the strong headwind component. First, we are very level so we will want to cut the power just before touchdown and flair a bit to protect the nose gear which hangs down lower than the mains. Also we want to guard against becoming so enamored with our slow, controlled approach that we allow the aircraft to drift backwards. Zero ground speed at touchdown is fine. -3 knots ground speed at touchdown is not fine. The apparent rate of closure approach, in a strong headwind, is like target fixation on a gun or rocket run. It just gets better and better and you have to snap out and say, "we need to finish this." Finally, we have to deal with gust spread, which usually accompanies a strong headwind component. We will have to move the throttle quickly and as much as necessary to get ahead of any shear or updraft or downdraft. We don't want to forfeit our very useful, for low ground speed on touchdown, flaps just because we have a headwind. I use full flaps on all approaches. When sinking fast, we need to put the throttle full in and then adjust. When rising fast, we need to pull the throttle full back and then adjust. In mild gusting we need to move, not adjust, the throttle as necessary to maintain the desired glide angle and desired rate of descent.
Downwind landings can get a little exciting. To get the same apparent brisk walk rate of closure, and the same ground speed, we would have to slow the airspeed more than our engine could handle in a 30 knot tailwind. However, crop dusters often set the auger truck up midway down a three thousand feet runway so ag planes can come from both ways to load dry material. Dry fertilizer will not weigh as much as a full liquid load and it is put out at hundreds of pounds per acre so there will be many takeoffs and landings. And the reason they are spreading instead of spraying is that the wind had gotten up. So how does the one landing downwind and then taking off upwind get it down in fifteen hundred feet in a ten to fifteen knot downwind? He will be using a lot of power to hold the very high pitch attitude necessary to slow the airplane down enough that he is approaching at what appears to be a brisk walk. And the loader up there doesn't want him to round out, hold off, float in low ground effect, and finally flair.
contactflying wrote:Nosedragger,
I have grandsons in Charlottesville, Va and Denver. We get to each place at least once per year. Do you ever go to Denver? We might get together there. I lost my medical and fouled up Light Sport so my wife won't let me have an airplane anymore. The argument that I wasn't always legal back in the day doesn't work at all with her. Fly for food? I'm desperate. I'll buy you lunch.
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mtv wrote:Here's one issue with these kinds of dpiscussions: When someone says "I use 80 on final (or on approach)", you should be asking two questions: First, as others have noted, are we talking knots or mph? Second, WHERE on final or on approach are you flying that speed? Are we talking 70 knots (or mph) on half mile final? Or at the threshold?

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