A student pilot has set off on his solo cross country flight. The EV-97 Eurostar has reached it's cruising altitude and the student lowers the nose before reducing power. Once the aircraft is stabilised he slowly pushes the trim lever forward until he feels the pressure disappear from the stick and the aircraft begins to hold a level flight attitude. In smooth conditions, it will now be possible for the student pilot to fly hands-off unless an altitude or course change is required. With the workload reduced, he now has enough time to communicate with ATC and navigate the aircraft. Taking the time to trim the aircraft correctly will greatly reduce the pilot workload and stress. In order to do this, you must first understand the correct process for trimming the aircraft.
Establish power and attitude first.
It is a common mistake to adjust the trim before the attitude and power have been correctly set. Using the trim in place of the elevator is guess work and will result in oscillations. Faced with such situation, the workload of a pilot increases instead of decreasing. We keep juggling with the trim and it soon leads to frustrations as the other tasks in the cockpit are calling us back.
Firstly, the stick should be used to establish the desired attitude and then power should be adjusted to maintain level flight. Once the aircraft has settled, the trim should then be adjusted only to remove the forces on the stick.
Understand how the aircraft will react when it is trimmed.
It is important to understand that an aircraft has the ability to restabilize. This means that you should not respond to every minor change in pitch during turbulence.
Most light aircraft are also speed-stable once they are trimmed. This means that any change in power will result in a change of attitude, but the speed will remain the same. For example, if the power is reduced during the cruise, the aircraft may momentarily decelerate, but then it will pitch down and accelerate back to the original speed, perhaps with a few oscillations first. This will continue until a pitch adjustment is made by the pilot or the airplane is reconfigured with flaps. Trimming the aircraft on approach.
An aircraft that has been trimmed correctly on final approach will be more speed-stable. This will mean that the pilot spends less effort concentrating on holding speed and can work more on the glideslope and runway alignment. However, the pilot should be aware of the trim position in the event of a go-around. Sharply increasing power from idle to full may result in abrupt pitch changes which could result in deceleration. Particular caution should be applied to airspeed and pitch attitude in this event.
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