Bob Fry wrote:
"jo" == jan olieslagers writes:

jo OK OK thanks but that wasn't really my question. Excuse me if
jo I wasn't clear enough, what I really meant to ask is "when
jo designing a plane, need I be concerned about the Reynolds
jo number

jo PS1 I am very happy with the tone of this discussion: only
jo positive reactions,

Hmmm. This may be the first negative one. If someone doesn't
understand Re, should they be designing an airplane? I don't think
one can pick up sufficient fluid and structural mechanics on Usenet to
be a reliable aircraft designer.

There are two kinds of design (and science, and lots of other stuff..)
incremental, and original.
As it happens, the great majority of design (and lots of other stuff) is
incremental. That's not such a cop out as you might think.

In terms of airplanes: you examine the mission. (EVERY airplane has a
mission, but some folks don't necessarily realise that)
Then, you gather data on every airplane with a similar mission.
Then (as best you can) you evaluate the positive user feedback, and the
negative stuff, and associate design features with the desirable features.
Then you try to package all the desirable features and none of the
undesirable features in one package. At NO point have I mentioned Re
have I?
I could even go a little further: if you get yourself in a situation
when you have to deploy your considerable engineering skills in
evaluating Re, it is because you forgot to use your even more
considerable judgment is selecting well-liked, useful, relevent airfoils.

:-)

Brian Whatcott Altus OK