[doviatt]

Frank is correct.
The downward lift on the tail of conventional planes is for balance. Engine weight up front down force in the back = balance. If the tail had upward lift it would have a tendency to decrease the angle of attack of the main wing by rotating the nose down and dive. This is considered an unstable condition with no self correction. Down lift on the tail creates a very stable balance at almost all air speeds and helps keep the main wing angle of attack in check. In the case of the Synergy with its rear engine the down force is to balance the pilot and passenger weight (short body length as was mentioned) up in front of the center of gravity.

Staggerwing is one of my favorite airplanes. I'm glad it got brought up even though I agree...nothing like the Synergy other than it has wings.