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I'm getting close to the first flight on my waiex. I am curious what you guys have found to be a good trim setting for takeoff? The plans call for rigging the ruddervator a so that the top skin is level with the top skin of the stabilator and should have 11 degrees of up from there (if I remember correctly). So I guess my question is how do you set your trim for takeoff? I realize this depends on trim spring setup and CG. Just looking for a good starting place.

Thanks!

Hi Sean,

Personally, I've always found that setting full nose down trim for takeoff works well for me. Once I'm in cruise, the trim will be centered and by landing it's full up nose trim.

Of course it all depends on how you have the spring tension set up on your Dial A Trim. Another option is simply set it at neutral at first and see how that works. Just remember that on takeoff, as you climb out the pitch you see prior to takeoff (three point attitude) is pretty much the same as your initial climb attitude. Don't let it get much higher in pitch of you wont have much airspeed!

The waiex has a very light stick and it isn't difficult to hand fly it with the trim way off if you don't get it setup right for first flight.

I set mine up per the plans and set the trim to middle range of the dial-a-trim. Made adjustments to the dial-a-trim spring attachment in subsequent flights.
I've since converted to a electric trim spring tensioner which has no indicator. So I take off with whatever trim setting I last landed with. Once in climb, its a simple trim adjustment to take pressure off the stick.

More than one Waiex pilot will tell you to use forward of neutral (neutral meaning ruddervators centered) trim for takeoff. Personally, I set the dial-a-trim to have the stick float about 1/3 the way from full down. Even if set incorrectly, it's not hard to overpower. Best of luck on the first flight...

I dial-in full nose down...But it wouldn't make much difference. I also lift the tail at around 35-40kts as it seems to improve directional control. The only time I've looked like heading for the trees was once when I left the tailwheel grounded because of a strong cross wind. I won't try that again.

I agree with Kip on the slightly forward of neutral. It's just a more natural feel to hold a little stick than to have to "push" stick. Especially on your first takeoff when your considering a full plate of matters that may or may not effect your first flight.
In any case just remember you can easily overpower even the full range of trim condition with a push or a pull. Good luck and enjoy that first flight.

Larry
Waiex 121YX, Jab3300 solid, 449 hrs

I use full nose-down for takeoff in all the Sonex aircraft. Once up and flying the trim can be easily adjusted if necessary.