thanks for this useful testing. So to use it you’d get the max L/D right at whatever speed that should be, set the mach parameter to 1 for that speed, and tweak the mach parameters lower at faster and slower speeds?
it’s hard to see how that would work with ‘normal’ polar curve that the flight sim already models, i.e. above some speed the drag already increases faster than the lift so the L/D decreases anyway. Although FSX has always had a big problem for gliders (I’ve modelled a lot of them) that the L/D (hence glide ratio) always improves as you slow down, until you reach the stall (sim power pilots/developers in my experience have never noticed this, and find it hard to believe) - maybe the mach table is ideal to address this for speeds below max L/D.