A properly built wing will have around 2 degrees of washout. That means from where the wing joins the fuselage to the tip, it will twist downward to the tip. The difference in angle of attack between the wing root and the tip should be around 2 degrees on most aircraft. (not just rc aircraft have washout built into the wing). What does all this mean? It helps decrease stall speed of the wing. While flaring the nose for landing, the wing tip angle of attack has not stalled and is still providing lift while the inner portion of the wing is near stalling thus, a more gradual loss of altitude is noticed.
Make sense?