"Richard Riley" wrote in message
...
You have a wind tunnel without a ceiling? Cool.

If you cannot be bothered to be clear about what you mean when you write "is
a real pain", I cannot be bothered to restrict my understanding of such an
ambiguous statement to such mundane issues as a ceiling.

An airplane in a wind tunnel can climb just as well as it can accomplish any
other action an airplane might do. Within the confines of the wind tunnel,
the airplane can behave completely normally, relative to anything an
airplane can do. Climbing or otherwise.

You have a treadmill that's a couple of thousand feet long? Cool.

The question specifically posits a treadmill long enough to serve as a
runway. In any case, you made no indication that your objection was based
on the length of the treadmill. Either way, you are missing the point.

Pete