The
glider will only be in perfect equilibrium for one speed/ AoA/ CofP/ CofG/ weight combination - when the tail force is
exactly right
At any other constant speed (or weight) the elevator
will have to be deflected to provide the additional appropriate tail force
If the glider is stable in pitch this means a pressure
will have to be held on the stick – which is no fun, as any experienced pilot knows
Trimmers are provided to eliminate this pressure
Elevator trim tab (works opposite to direction of elevator movement)
TRIMMIMG
Spring
trims (moves ‘neutral’ position of stick)
–e.g. K21/23
–No extra drag
Trimmed for
‘nose heavy’
–e.g. K13
–Extra drag (of
tab)
Trim lever