How to Trim a Trainier for Flight

How to Trim a trainier for flight

Neil Udell, Steve ????, Bob Smith from CAMS

Construction

Build it straight

Remove warps

Equipment Installation

Steering

Balance

CG

Lateral

On the main gear

Flight Trimming

Take Off – Optional

Landing – Mandatory

Goal of flight trimming

Glide to a landing –hands off.Take off – hands off. You don’t actually have to do this, but the plane should be able to do this.

Controls

Throttle – primary control for altitude

Aileron – primary control for roll

Elevator – primary control for turn (after the bank). “Bank-and-yank”

Anticipation – Planned Flight

Be ahead of the plane. Fly the plane, don’t let it “fly” you.

Aircraft Atittude – landing, take off, climb: all the same slightly nose high attitude.

The Perfect Glide

Center your elevator, rudder and aileron trim adjustments on your transmitter.

Trim Adjustment

Take off, fly to an appropriate altitude, level the wings and go to low idle.

Observe the plane and adjust your trims to compensate for roll, pitch and yaw.

Reposition for another glide trim pass and repeat.

Land.

Adjust Control Surface Settings

“Listen” to your trims. Move surfaces in the direction your transmitter trims are from center.

If your trims are set for down elevator and right aileron to achieve the “perfect glide”, then adjust your elevator clevis to give you more down elevator and your aileron clevises to give you more right aileron. Then set your trims to the center and try another “perfect glide” trim flight. Repeat this until you get the “perfect glide” with the trims centered.

Powered Flight

Engine Thrust Adjustment

Once you’ve achieved the “perfect glide”, go on to adjust engine thrust for powered flight. Set up for a "perfect glide” and go to idle. Go back to full throttle and carefully observe the airplane. The plane should transition to a gentle climb along the same line as the “perfect glide” path. Make several passes to verify that you know what the plane consistently does when you go to full throttle.

Land the plane. It usually works best to adjust engine thrust in one direction at a time. Adjustments are made by shimming the engine mount with washers or thin hard material. The first adjustment to make is for up or down thrust. If it climbs, you need to add down thrust. If it dives, you need to add up thrust. Adjust in small increments.

To the right, you need left thrust and to the left, you need right thrust.