Fa2004 16.3332-5 Contribution of the tail Z aFRL Some lift provided but moment is the key part Key items 1. Angle of attack at=aFRL +it -E, E is wing downwash 2. Lift L= Lu+ lt with Lu > Lt and CL= CLm+nCCL 7=(1/2pV)/(1/ 2pV2)0.8-1.2 depending on location of tail Downwash usually approximated as de d where Eo is the downwash at ao. For a wing with an elliptic distribution C de 2C ar doFall 2004 16.333 2–5 Contribution of the Tail FRL FRL �W �FRL i w i t Lw Lt Dw Dt Macw M t Zcgw V V l t V' Zcgt � c.g. ac • Some lift provided, but moment is the key part • Key items: 1. Angle of attack αt = αFRL + it − �, � is wing downwash 2. Lift L = Lw + Lt with Lw � Lt and St CL = CLw + η CLt S η = (1/2ρVt 2)/(1/2ρVw 2) ≈0.8–1.2 depending on location of tail 3. Downwash usually approximated as d� � = �0 + αw dα where �0 is the downwash at α0. For a wing with an elliptic distribution 2CLw d� 2CLαw � ≈ = πAR ⇒ dα πAR