Total Lift Force = Airplane Weight + Tail Down Force 2150 pounds = 2000 pounds + 150 pounds Table 1 Lift Force =

Coefficient of Lift * Air Density / 2 * Wing Surface Area * [Airspeed.sup.2] Table 2 CG LOCATION AND SPIN RECOVER

[S.sub.l,pl] Shape coefficient of lift 12 t Wave period 1 [t] Average wave period 1 [t.sub.r] Return time 1.14 u Water velocity at the substratum 3 U Maximal water velocity 9 x Breaking force 22 [Chi] Mean breaking force 22 [Alpha] Coefficient of proportionality 2 [Beta.sub.d] Velocity exponent of drag 7 [Beta.sub.l] Velocity exponent of lift 12 [Zeta] Density of water 7 [Tau] Interval of time 1 [Tau.sub.i] Interval of time 1.17 [Tau.sub.tot] Total time 1.10 [Sigma] Standard deviation of breaking force 22

where [Beta.sub.l], is the velocity exponent of lift and [S.sub.l,pl] is the shape coefficient of lift, defined using the object's planform area.

Second, deployed flaps increase the

coefficient of lift of the wing and make it more efficient.

The resulting yaw brings the left wing forward, decreasing [alpha] and thus bringing it back to the front side of the

coefficient of lift curve and increasing lift.

Aircraft manufacturers, NASA and the de-ice equipment purveyors have done enough research to demonstrate even relatively benign ice accretion--if there is such a concept when it comes to icing--on a wing's leading can reduce the maximum

coefficient of lift by as much as 30 percent, according to Dennis Newton's excellent treatise on the subject, Severe Weather Flying.

There are several useful and well-known kinds of performance curves out there in "Theoryland." Among the first to which we're introduced is the one depicting the steady rise of a dimensionless number called the

coefficient of lift with increasing angle of attack, increasing at somewhere around 0.1 per degree up to anywhere between 1.0 and 1.8, and leveling off at this thing called [CL.sub.max], represented as the top-most point of the red line in the chart at right labeled "Lift vs.

As the angle between the wing chord and the relative wind is increased for a given airfoil, the

coefficient of lift increases.