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I'd like to use a tapered wing with 0 deg leading edge sweep and 12 deg trailing edge sweep as shown below for my RC model. I understand that lift curve slope, a, is reduced for wings with leading-edge sweep since the normal velocity component is lower than the freestream velocity, resulting in a lower pressure difference between the upper and lower wing surface.

Would there be a reduction in lift curve slope or any other performance (compared to a straight wing, with no sweep), for my wing with only sweep at the trailing edge?

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    $\begingroup$ Since we are talking about an RC model, the different Reynolds number between tip and root might have a not negligible impact. Plus all what @Koyovis has already explained. $\endgroup$
    – sophit
    Feb 4 at 11:49

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Would there be a reduction in lift curve slope or any other performance (compared to a straight wing, with no sweep), for my wing with only sweep at the trailing edge?

1. Lift curve slope. Leading/trailing edge edge sweeps of 0° & 12° yield a quarter chord sweep of 3°, which is very little. When for instance using the simple sweep theory like in this answer, wing lift coefficient $C_L = c_l \cdot$(cos$\Lambda)^2$ reduces by (cos 3°)$^2$ = 0.997 = 0.3%.

2. Any other performance. Stall characteristics might be slightly improved, since the trailing edge will deflect the flow slightly in the wing root direction, so full aileron control in a stall. You might find more info in the answers to this question, although they pertain more to faster planes with higher sweep angles.

3. Structural implications.. The usual issues with forward sweep are increased tip torque and increased flutter tendencies, which requires stiffer torsional construction. But again, with a straight leading edge and only 3° forward sweep there should be no serious consequences.

enter image description here

Above picture (from Wikipedia) shows the L-13 Blaník. Quoting the Wiki article, it is the most numerous and widely used glider in the world. It has slight forward sweep for positioning the instructor not above the main wing spar, and has very favourable handling characteristics.

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