Wortmann vs Eppler

I think the subject is better stated as "Wortmann and Eppler", not versus. But one time Bruce Carmichael, Paul MacCready and I were discussing how Dr. Wortmann's sections seemed to enjoy more usage and success than Eppler's. When the discussion turned to "why", Carmichael said: "Don't forget that Wortmann had the tunnel".

Eppler's genius was evident upon bringing us the inverse design method- a remarkable achievement. Something which was then ingeniously expanded upon by Mark Drela when wake effects could also be taken into account. However, as Carmichael wisely pointed out there's great value in empirical results. This still applies to the best CFD. Irv Culver was fond of reminding: "One test flight is worth a thousand expert opinions", which I suppose is in a similar vein and stated only as Irv could.

It's sad to think that all these great contributors are now gone. As is Dennis Brown, a flight test engineer from Boeing who spent untold hours contouring his Mosquito wings to near perfection. He saw very little benefit, if any, after careful testing and measurement. Doesn't mean others haven't enjoyed good improvement with other situations. Dennis is gone now too. I miss these guys.

-Gary Osoba