Together with John Donovan, Selig designed the SD 7037 and the SD 7032 in 1987. The SD 7032 was made as an improvement over the E 214, and the SD 7037 was a thinned and decambered version of the SD 7032. In the beginning these two airfoils were fighting it out in low-level thermals – as you probably are aware the SD 7037 won, and this was probably caused by the lack of speed potential from the SD 7032. If you ask Adrian Lee they just didn’t build it heavy enough. SD 7037 is thick enough to build a strong wing, it can fly slowly but it can also penetrate with a good gliding angle. Pour in some lead and you can pretend you have a F3B model from the beginning of the eighties. If all you want to do is find thermals and soar with the birds, this is a good one to choose. It’s not specifically designed for the use of flaps, but like most airfoils you can turn the trailing edge a bit up and the plane travels faster, add a few millimeters of down flap for those very tight circles. The last may not lower you sinking speed, but it’ll lower your flying speed and thereby help you to turn tighter. SD 7037 has been one of the most used airfoils in the only international pure thermal gliding class – F3J, although it looks like the MH 32 or versions with a bit more camber than MH 32 and less than SD 7037 may take over. After reading Adrian Lees first article though, it may seem that SD 7032 still have something to offer to thermal pilots and I bet that Adrian’s article will make a few think about airfoils and F3J designs again - I did. I looked in Soartech again and found the polar of the SD 7032 and it reveals that it has quite a high lifting capability (high Cl) – Cl=1,2 - like Adrian writes, and that it follows the unflapped S 3021 down to Cl=0,2 with 3 degrees negative flap when we are talking drag. Compare this with the S 3021 max-lift that is about Cl=1,0 without excessive drag. What this means is that the SD 7032 is better than the S 3021 and some other airfoils when flown fast with negative flaps, flown at moderate and slow speed with neutral flaps and maybe with positive flaps when circling very slowly and tightly. This was also what was stated in the Silent Flight pullouts from somewhere in the nineties. A year ago I would have said “Choose SD 7037” to anyone who asked for an airfoil for thermal flight but “now I’m not so self assured” as Beatles wrote many winters ago. Looking at Adrian’s models suggests that when using SD 7032 you don’t have to be too concerned about aiming at a very low wing loading. It’s easier to build strong and heavy than to build strong and light.