Posted for "Rick Lafford" <gliderguy89@earthlink.net>:

 How about checking the wing fuselage junction and the underside of the wing.
 A somewhat more sensitive method is to brush on a coat of used diesel oil,
 fly the a/c while taping then land to give the flow pattern a close look.
 Any flow disruption will really stand out. Can be done both top and bottom
 but I'd expect a separation bubble on the lower surface. After the test we
 use a citrus based cleaner to de-mess the wing.
 
 Rick Lafford
 Dansville, NY


"""
  Well, being a future air racer, I thought I would be a good experimenter
 and find out how the airflow acted over the top of my wing at different
 airspeeds. I dutifully tufted a section of the top left wing with cotton
 tufts and launched with a video camera.
"""