# Equilibrium of the Aggie Micro Flyer

The AMF III has a span bm = 2.1m and a constant chord cxm = 0.263 m. The corresponding tail is defined as bt = 0.527 m with constant chord cxt = 0.176 m, using the rapid prototyping code, which also provides the take-off velocity Vto =

13.7 m/s and a maximum take-off mass M = 15.5 kg.

14.5.3.1 Airplane Lift and Moment Curves

The equilibrium code calculates the lift and moment coefficients for the complete configuration at low incidences to be:

CL (a, tt) = 4.47a + 0.37tt + 1.11
CM, o(a, tt) = -1.30a – 0.33tt – 0.28

where a is the geometric incidence (in radians, measured from the fuselage axis) and tt is the tail setting angle (in radians). CM, o is the aerodynamic moment about the origin of the coordinate system (located at the nose O).

What is the effective aspect ratio AR for the complete configuration? Compare it with the main wing aspect ratio ARm. Explain the difference. (Hint: look at how the total lift coefficient is calculated).

Find the location of the aerodynamic center xac given that lref = 2.062 m.