> In regards
>to the question 'What is
>the goal?', I agree that
>at least a qualitative goal
>would make the discussion more
>meaningfull.
>However, although I have great respect
>for his modeling achievments, I
>feel he is not giving
>sufficient credit to the affects
>of Airfoil Parameters. As he
>indicates, it is desirable to
>achieve maximum lift without stalling,
>but a review of any
>empirical or theoretical study of
>Airfoils clearly shows that both
>the shape as well as
>the thickness of an airfoil
>can significantly affect the Lift
>& Drag characteristics of a
>wing and change it's angle
>of attack at stall. It
>is true, however, that the
>L.E. radius does have a
>significant effect on these properties.
>
>
>
> Joel
>Chesler, Knights of the Round
>Circle
>
> Joint
>Strike Fighter Program, Northrop Grumman
>
>
Joe,
Of course, all you say is absolutely true. Especially if one is in search of ultimate performance in one phase of flight or another. Many other details...such as Reynolds numbers reflecting effeciency based on pure size of the airfoil...are very real and measureable phenomena.
If, for instance, your goal is ultimate speed and nothing else you can refine your airfoil choice accordingly. If maximum duration is the ultimate goal other airfoil choices would be more desireable. Note, however, that in each case a goal was necessary before any conherent search can be instituted. In the case under consideration, that part of the equation was left blank.
Note, also, that although the airfoils desireable for the above mentioned rules could have a dramatic effect, it is also true that aspect ratio, planform and wing-loading would probably be an even greater concern. I.e., you probably wouldn't build the strike fighter with a 30 to one aspect ratio unswept wing and expect it to fly supersonically--or stay in one piece--regardless of the airfoil choice. Nor would your max duration design likely have a two to one aspect ratio delta wing regardless of the airfoil choice.
In all cases, the mission defines the discussion...form follows function.
In the case of our stunters we seek nothing so esoteric as maximum anything. We need an airfoil which avoids stalls until such time as adequate lift is generated to accomplish our goal...a reasonably sharp corner.
Given adequate area and a reasonable aspect ratio, a flat plate has proven capable of reasonably competitive performance (you guys Down Under help me out here with the name and some details regarding your "flat plate wing wizard"). Sure, it'll get better with a "better" airfoil but the changes necessary to make it "better" probably don't require years of advanced aerodynamics or a Cray computer.
On the other hand, the very best airfoil that could be conceived with all the aforementioned years of training and the best computers wouldn't perform the stunt pattern as well as the flat plate previously mentioned if the wing loading was excessive and especially if the aspect ratio was something extreme...like one to one as is used by some trainers such as the Flying Platters Bill Osborne has used for years to train young controliners.
Yes, airfoil refinements are very real and in the world of full scale aviation...whose missions vary from utmost speed and maneuverability regardless of cost (well, almost regardless) to absolute minimum specific fuel consumption (commercial airliners) a characteristic of any sort that results in even a modest enhancement of the mission is critical. The winglets on a modern airliner like the 747-400 are a perfect example. Tons of engineering and manufacturing expense were invested to achieve an increase in specific fuel consumption in the sub 1% range...tiny but worthwhile over the operating life of the plane and given the volatility of oil prices.
For us, I just don't think such refinement is the holy grail. I think the Moon boys and 'zilla have merit in their assessment of the value of thicker airfoils and I have been more or less in the forefront of those "designers" using them. Nonetheless, the assessment that a thicker airfoil with a more rounded entry is superior to a thin section with a sharp entry is a fair distance removed from the suggestion that there is a "magic" combination of airfoil co-ordinates or a specific shoe sole size that will overnight render such "airfoil banality" to the scrap heap.
Once again, the mission must be defined before we can make either strategic or tactical plans to assault it! (Ooooh, boy. Too much war talk going on nowadays) 
Ted Fancher