I have a problem with my elevator trim tab, this is a
IV-P so perhaps it does not have the same
characteristics. When coming down for landing the
force by the airstream prevents the trim to move, in
the ground the function is perfect, it goes up and
down without problems it never happens on trimming for
take off only when landing, there must be an airflow
disturbance at times when trimming in the air i had
the trim go the opposite way forcing me to use a lot
of force in the stick to maintain level flight  and in
ocassions i had to cancel the flight plan since the
trim will stick in the opposite complete end and once
in the ground the problems resolves. Any ideas?
the plane is currently at the factory and the a+p
there are looking at it.
andres