The central section of around 180mm has a lower angle of attack than the outer parts. Like several others, this is achieved with a lower trailing edge and a higher leading edge. The secondary element has a profile to match to match the main plane, but the trailing edge is flat. The camber of the wing as a whole is therefore greater in the central section than at the edges.
Like the other main planes, it has a span of 363mm and a chord of 146mm. The flap is fitted with a small gurney flap 3D printed using SLA and attached with double-sided tape and aluminium tape.
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