**Edit:** this question is about making clear that the Wikipedia's article about the Kármán line is an **interpretation**, **not the definition !**

Why not consider the Kármán line as a curved boundary that follows the curvature of the Earth ?

According to Wikipedia's article about the [Kármán line:](https://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_line#Definition)

> 
> The Kármán line is the altitude where the speed necessary to aerodynamically support the airplane's full weight equals orbital velocity ( assuming wing loading of a typical airplane )………………………………………………………………………………………………………………...The Kármán line is therefore the highest altitude at which orbital speed provides sufficient aerodynamic lift **to fly in a straight line that doesn't follow the curvature of the Earth's surface.**
> 
> 
> 

Note: this is an **interpretation** of the writer of the article, **not the real definition !**

The [FAI (Fédération Aéronautiqe Internationale)](https://en.wikipedia.org/wiki/F%C3%A9d%C3%A9ration_A%C3%A9ronautique_Internationale) that adopted the definition, doesn't mention any **straight line** in [this article](https://fai.org/page/icare-boundary) about the **100km altitude boundary for astronautics**

So would not the definition of the Kármán line be better **explained** by an airplane **in orbit** around the Earth, rather than by an airplane flying in a **straight line ?**