the thulin fa was a two-seat biplane with the lower wings mounted at the bottom of the fuselage. the upper wing was supported by four wing struts and two v-shaped supports from the fuselage. only the upper wings were fitted with ailerons. the fuselage was provided with two open cockpits in tandem under the upper wing. the wheel ground was fixed with a spur spring under the height knob (??). the type fa was alternatively equipped with floats for water operation.