Tandem wing

A tandem wing aircraft has two main wings, with one located forward and the other to the rear. Both wings contribute to lift. 
Tandem wing aircraft may be distinguished from:
Design principles.
A tandem wing configuration has two main wing planes, with one located forward and the other to the rear. Compared to a conventional monoplane, where the tailplane exerts a balancing downforce, both tandem wings contribute to lift. In aircraft such as the QAC Quickie Q2, the forward wing may double as support for the landing gear.
In a tandem wing design the lift vectors on the two wings are spread far apart longitudinally, allowing them to act in concert to achieve stability and control.
Tandem wings have also been used on ground-effect vehicles.