Aileron trim attachment and wiring

Attaching the aileron trim servo to the pushrod is pretty simple, and involves marking the neutral position, then attaching a bracket 6 inches to each side:

Aileron trim attachment points in right torque-tube-to-bellcrank pushrod

The servos and pushrods will then be connected by springs.

For securing the servo wires, I used a Panduit RAMH-S6-D attached through the same screw as the servo:

Aileron trim servo connector attachment

This will keep the wires away from the moving side of the servo and can hold a connector in place. For the connector, I picked a mini AMP CPC 5-pin (1445820-11445829-3, 1445856-1) which has pins for the 26-gauge servo wires (770985-1770986-1). Those pins are 26-22 AWG, so I can just 22 on the other end and not have to deal with tiny wires.

Mini CPC for aileron trim servo

Crimped all the pins (it was slightly annoying, since the pin edges do NOT sit flush on the wire end of the crimper when the pin is this small), slipped on braided sleeving and some heat-shrink (just in case):

Aileron trim servo pins crimped

Inserted the pins into the receptacle and closed it up:

Cable coming out of aileron trim servo, with connector

Shell size 11 is small, but not that small (unfortunately shell size 8 only takes up to 4 pins, and I needed 5).

Full connector/receptacle pair atached to aileron trim mount

(and, for my own record, the pinout I used was 1,2-power; 3-green, 4-blue, 5-orange)

With this, the only thing left on the aileron trim is actually installing it in place and wiring it to the AP servo, which will come much later.

Time lapse:



Total aileron trim rivets: 16
Total aileron trim time: 8.1h

Aileron actuation complete

When I installed the ailerons in place, it became apparent that they were not aligned properly - the inboard end of both ailerons was catching on the bracket's rivets:


After consulting with Van's, this was solved by shifting it outboard a bit with another washer and shortening the spacer:


I then proceeded to installing the torque tubes and pushrods. I decided to do this before attaching the bottom outboard skin to make adjustments easier:

Torque tubes and pushrods attached
Template holding bellcrank in neutral position

Aileron near neutral position
The last part - adjusting the length of the bellcrank-to-aileron pushrods - required installing the flaps temporarily:

Flaps installed for adjusting the aileron actuation

then using them as a reference for the ailerons:

Aileron and flaps well aligned

Adjusting the bellcrank-to-aileron pushrods


I removed the ailerons, flaps and pushrods again after adjusting the pushrod lengths, but the only step left is to reinstall them after the bottom skin is riveted.

Time lapse:


Total aileron actuation rivets: 40
Total aileron actuation time: 22.1h

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