"Dan" wrote in message ...

I would think a simple solution would be to have an indicator with
range marks for common flap settings. It's not perfect, but if you
usually use one setting for take off, one for landing and clean for
flight you should be able to SWAG other settings based on those range
marks.

Dan, U.S. Air Force, retired

A thought just crossed my mind. When you change the flap setting the angle between the fuselage and the effective chord of the airfoil (angle of incidence) changes. At the optimum L/D speed at various flap setting, I bet there is little change in airflow relative to the fuselage.

If you are flying with the fuselage nose down, or nose up relative to the airflow, drag is created. So my guess is that a well designed sailplane fuselage flies at an angle of 0 degrees to the airflow at best L/D regardless of flap setting.

This is just a gut feeling. I'll have to tape a string to my canopy and mark its' location at best L/D with a zero flap setting and see what speed I achieve maintaining that mark at various flap setting.

Wayne
http://www.soaridaho.com/