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by histriosum 2319 days ago
The ground speed will vary, but the airspeed will not be affected by wind (except momentarily for gusts or shears).

The poster I replied to was implying that due to the strong tailwind, they had to maintain an increased airspeed. That is incorrect. The airplane has no idea it is in a tailwind, and airspeed will be unchanged.

3 comments

I think the root of disagreement here is that to you, as a pilot, "speed" means airspeed. But to a layperson, "speed" means groundspeed. So saying that an airplane with a tailwind "must go faster to keep enough air going over the wings" reads very strangely to you, as (although it is technically correct) it belies a groundspeed-first type of thinking that is a poor intuition for staying alive in a plane.
> The poster I replied to was implying that due to the strong tailwind, they had to maintain an increased airspeed.

No, he wasn't. He explicitly said the opposite:

"higher ground speed to keep the same relative air speed."

I think the confusion here is stemming in part from the fact that "relative airspeed" isn't a well-defined term. In aviation airspeed means the speed of the airplane through the air (modulo specifiers for true vs. indicated vs. calibrated airspeed).
> "relative airspeed" isn't a well-defined term

The original was "relative air speed", which I would simply take as the way a person not familiar with aviation terminology would say "airspeed"--speed relative to the air.

I don't think anyone other than you interpreted the comment that way.
I did. Saying “everyone” when it’s just probably one person is not usually ok. It’s fine to say if you interpreted the comment in a certain way, and ok to be the outlier. But assuming your interpretation applies to others more broadly than it does, is counterproductive.
Both comments were significantly downvoted at the time of my comment, which was what I was referring to. The original comment explicitly mentioned "relative airspeed", which I thought was pretty clear (it's the speed of the plane relative to the air that matters).

I think calling it a "common misconception" is also assuming a lot.

I teach people how to fly. Trust me when I say that this is an extremely common misconception. It's one of the concepts students have the greatest difficulty wrapping their heads around.
Do these people never use treadmills or trains?