Test Equipment/Simulator

I finished up my Simulator for the new Ultimate Trim Relay Board and thought I would post some photos. I think it illustrates just how simple it is to wire two grips (with all the bells and whistles) using this hub concept—where all the wires from the grips go to the “input” D-sub connector and the “output” side is the gateway for all of the grip functions. Every one of the new relay boards gets a workout on the Simulator before it gets shipped (click on photo for enlarged version).

The Simulator

I have been getting excellent feedback from folks who have bought the relay boards. I wanted to emphasize that every relay board that I sell gets thoroughly tested before it gets shipped.

The flap actuator you see on the Simulator is an actual Usher Industries actuator as sold by Van’s Aircraft. I have done some testing with the flaps on my RV-6 to try to determine the amperage load during flaps operation. On the ground (or unloaded), amperage draw is slightly less than 1 amp. In flight, and within airspeed limits for flaps operation, amperage draw going down is between 3 to 5 amps, peaking towards the end of the cycle. It’s kind of hard to read the amperage because it varies so much as the flaps are moving, but on average the maximum load seems to be as flaps approach full down, and that’s about 5 amps or less. So I estimated that it would take about a 10 pound pull on the flap actuator to simulate (approximately) the load on the flaps in the airplane. I found a door spring, which you see here, that gave me about 10 pounds of force at 5″ of extension (flap actuator travel is 5 inches). The result is that I get almost the same amperage indications on the simulator as I do in the airplane, perhaps a little more on the simulator.

Actual Usher Flap Actuator


I used two old RC servos that I modified and loaded properly with resitors to simulate the electric trim servos we use on the RVs.

As it works out, this test rig will also serve nicely as a demonstrator at fly-ins, etc. Hope to see you with the Simulator someday soon at a fly-in somewhere!

And here is a photo of the original test equipment that I use for the smaller relay boards (lower right).

Anyway, I have trim relay boards available for most, if not all, grip configurations, so if you are approaching that phase of your build, please check out the web site and consider giving one of these a try.