L-birds or "Maytag Messerschmitts"

L-2 Taylorcraft

L-3 Aeronca

From Plane & Pilot, February 1999.

Below, photos from a Piper L4 at the U.S. Air Force Museum in Dayton, Ohio.  Aircraft controls don't get simpler than this.

 

For more info on wartime liaison aircraft, visit Lbirds.com.