figure 4.13. If the elevators of the airplane are 
fixed at zero deflection, the resulting line of 
CM versus C’s for 0’ depicts the static stability 
and trim lift coefficient. If the elevators are 
fixed at a deflection of 10” up, the airplane 
static stability is unchanged but the trim lift 
coefficient is increased. A change in elevator 
or stabilizer position does not alter the tail 
contribution to stability but the change in 
pitching moment will alter the lift coeflicient 
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