Smooth Skies: a Pilot's Best Friend

By Wayne Arbon.A properly-trimmed aircraft increases fuel efficiency
Are you a pilot and seek the secret to a smooth, easyby reducing drag. A climbing aircraft has a tendency to
flight?yaw which increases parasitic drag because more of
If you are forever wrestling with the controls and youthe fuselage is facing into the wind.
have aching arms when you land, you are not usingElevator trim balances the control force necessary to
the pilot's best friend - the trim wheel.maintain the aerodynamic down force on the tail.
Trimming the controls allow a pilot to balance the liftCertain flight configurations, such as slow flight, require
and drag being produced by the wings and controla lot of trim to maintain the desired angle of attack.
surfaces over a wide range of loads and airspeeds,Trimming increases aircraft stability as a
reducing the effort required to adjust or maintain aproperly-trimmed aircraft will return to the same
desired flight attitude.attitude and airspeed after encountering any
A properly-trimmed aircraft can be flown literally withdisturbances such as turbulence or gusts of wind.
your fingers lightly on the controls. Get into the habit ofThere is also trim for the rudder and ailerons used to
trimming every time you change attitude or powercounter slipstream or the effects of the centre of
settings, first letting the aircraft stabilise into the desiredgravity being to one side.
attitude.This can be caused by a larger weight on one side of
Use small corrections and take the time to trimthe aircraft compared to the other, such as when one
correctly - the aircraft will naturally want to stay infuel tank has a more fuel in it than the other or when
equilibrium whether in straight-and-level flight or in athere are heavier people on one side of the aircraft.
constant ascent or descent.Aileron trim is found mostly on large fixed-wing aircraft.
If you can take your hands off the controls and theIf the aircraft has a rudder trim wheel, use it - it's a lot
aircraft stays in the same attitude, it is trimmedeasier than flying with one foot on a rudder pedal to
correctly.centre the ball.
The most common example of a trim tab is theTake the time to learn the skills of correct trimming
elevator trim found in almost all aircraft. The elevatorand you will be surprised at just how easy a
trim tab is adjusted to maintain the angle of attackproperly-trimmed aircraft is to fly.
without pilot interaction.