INTRODUCTION This Item provides a method to obtain the increment in pitching moment coefficient at zero angle of attack@ due to deployment of trailing-edge split flaps@ either on an aerofoil or on a wing. For aerofoils the method predicts the centre of lift position@ h2@ due to split flap deployment@ based on the thin aerofoil theory of Derivation 19 and modified to obtain correlation with the experimental data of Derivations 5@ 6@ 12 and 17. This is combined with the increment in aerofoil lift coefficient calculated from Item No. 94029 (Derivation 1) to estimate the pitching moment coefficient increment. For wings with full-span trailing-edge split flaps@ factors@ dependent on planform geometry@ are applied to the pitching moment coefficient increment on an aerofoil section that is representative of the wing@ to allow for three-dimensional effects. For wings with part-span trailing-edge flaps@ additional factors are introduced that are dependent on the wing taper ratio@ aspect ratio and sweep as well as on the spanwise extent of the flap. Derivations 20 and 21 were used as the basis for three dimensional effects@ with some adjustment to the simple theoretical assumptions. Section 3 describes the prediction method and Section 4 discusses Mach number and Reynolds number effects. The accuracy and applicability of the method are addressed in Section 5. The Derivation and References are given in Section 6. Section 7 presents a worked example that illustrates the steps of the calculation