ORIGINAL: onewasp
Can't let this one go !
Separation DOES occur before the TE ----well before in most cases. A sharp TE increases the flutter possibilities markedly.
Read Dick Hanson above! Kamm "as in Kamm backed cars etc." determined that there was an "ideal" length of taper to create the least drag. Since this is generally "way beyond" the reasonable limits, he then determined that the best compromise was to cut it off flush at the desired point and that, would yield the best compromise. This was proved in actual wind tunnel test and these data are available.
Do a search on KAMM or hopefully one of the real aerodynamicists on RCU, like Ben Lanterman etal will comment tonight. TallPaul already has commented but in a less than pointed way. He too may re-visit this exchange before the evening is over.
onewasp,
I'm a little familiar with Kammback cars, and Kamm's work. If you look at cars built for absolutely minimum drag, such as solar powered racers, you will see no Kammback designs. Passenger cars, built to fit in standard parking spaces, be driven on real roads, and carry people & their cargo, cannot afford an optimally tapered back end, and may have to make do with a Kammback. An airfoil designed for minumum drag will not separate before the trailing edge, and will have a sharp trailing edge. The airfoil on model plane may be different matter, but that is not what ptxman was asking.
banktoturn