ELEVATOR TRIM

[fastj22]

The Viking Waiex had dual trim tabs before the transformation to the Viking Sport. I didn't notice if the sport still had them.

[sonex892]

I am building ONEX 0176 and would please like a general consensus of the need for the elevator trim system. I have had some builders voice that the system isn't necessary. I would certainly like to hear from those who have finished and fly their ONEX as well as other builders opinions.
Surfly

Probably personal choice with this one. I built a Sonerai 2LS before the Sonex. The Sonerai plans show no trim, most builders and flyers claim it isn't needed. I put a trim in my Sonerai during the build and quite liked being able to trim it in flight. If after flying your Onex you find you don't use the trim remove it. It is possibly easier to remove the trim system than it would be to install it later.

Don't know what trim system the onex uses. I use the trim tab in the sonex and I like it.

Steve
Sonex 892

[Onex107]

Just sayin. I'm flying Onex 107 with the standard trim system. Mounted vertically on the main spar on the left side. The stick load is so light that I don't think about trimming until I'm leveled off and testing the hands off balance. As the furl burns off, 5 gal. makes a small difference, I might make a change, but after refueling on the next flight I don't zero before takeoff. The elevator is so sensitive in pitch and the stick load so small it isn't a problem. Being a single place airplane the only load that changes is fuel.

[Spaceman]

You would have to get rather innovative to put trim tabs on the Y tail. Just go with the spring system.

I started out with the DialATrim on my Waiex. I didn't like the limited travel of it and couldn't find a happy sweet spot.
I removed it and installed an electric trim of my own design using a 12V motor, cable spool and the same spring from the DialATrim.
Works great and I wired it to the up/down on a 4 way high hat on the stick. I put in another system to trim the ailerons on the left/right switch. It just biases springs on the aileron rods using the same winch spool on a small 12v Motor.

John, do you have any more details or pictures of how you did your electric trim setup? I'm building a Waiex and that's exactly what I want to do!

[Onex107]

I use the standard spring trim on my Onex. I don't adjust it until at cruise and then it's usually to compensate for a change in amount of fuel. After burning off five gal. you will have a slightly nose heavy condition. The only way to tell is if you fly hands off and it doesn't hold the horizon. The stick loads are so light when out of trim there is no need to change when landing or taking off. The single place Onex doesn't have the trim problems that the Sonex does when with or without a passenger. I did relocate my trim wheel from the throttle location to a vertical mount on the front of the spar. It puts it next to your left knee and you can palm it instead of using finger tips. And it's less of a knee knocker under the panel.