Originally Posted by
pilotho
........surely, using a low wing design would improve ground effect and further improve STOL attributes........
The problem is that during certification, the time that ground effect really helps, i.e. the airborne segment from Vloff to V2 and onwards to the end of the 1st segment, you're not allowed to take credit for it.
Of course, in the real world, it genuinely helps, but you cannot increase your payload by 1 gram because of it, RTOW calculations are not permitted to use it.
Regards,
Old Smokey