Double Slotted Flaps: “A type of trailing-edge flap. They form two slots between their leading edge and the inside of the flap well in the wing. The resultant airflow helps to control the boundary layer, resulting in higher maximum lift but not so much increase in drag. The stalling angle also increases considerably.”
Anybody who has seen Wes’ Velvet-3 has marveled at the double slotted/blown flaps installation. The premise is to mimic the highly effective double slotted flaps used on airliners and other heavily loaded aircraft. Of course, Wes’ challenge was to design the flap mechanism so it would provide the benefits when deflected in either direction. Wes’ design “slaves” a 1” wide slat between the wing and the main wing flap. The slat deflects ½ as much as the main flap as it also opens airflow slots that help energize the flow over the top sides of the flaps. The system is also designed such that the flaps can be built and finished off the wing, then assembled after finishing. The slats and flaps ride on full span CF rods that are captured via a removable end cap.
Wes'design is now committed to CAD and is available as a set of laser cut parts. Each laser cut sheet (1/16" ply) consists of enough parts for one airplane (both flaps). There are two variations of the flap hinge system available. Wes' original Velvet-3 design uses a single sided underslung loop to carry the slats and was intended to minimize the visible hardware on the top side of the flap. there is also an alternate design that allows the hardware to be centered over and under the flap but is minimized in size to help hide it.
Several people have expressed interest to Wes about his flap system. He is working on an article for Stunt News but in the meantime call Wes [(260) 341-6024] if you are interested in obtaining a set of laser-cut hinges for the double slotted flaps.
Topic: Wesley Dick’s Double Slotted Flaps - Kit Parts Available (Read 3260 times)
