Today I epoxied the stabilizer on the tail of my Big Stik 40. I used 30 min. epoxy. It I was lined up perfect with the wing when I left it to dry. But my fan blew the fuse to the side and the stabilizer is now set a few degrees off parallel from the wing . Will this have a major affect on the the plane flies?[sm=confused.gif]

Depends on what you mean by 'a few degrees' and 'major'.

Will it impact how the plane flies? Yes, absolutely. Will it make the plane unflyable? PROBABLY not if it's truly only a 'few degrees'

Most likely, if it's not bad, a little trim in flight will probably null it out. To be sure, however, we'd really need to see a picture, or at least get a better idea of how far off it is. Can you set the plane down level, and measure table to stb tip on each side, and tell us how far apart the measurements are?

See diagram

Ken

If this is your first season flying and your second plane, I doubt you will able to notice the difference. We have a guy here whos stab was off a bit on a 120 size plane, so he sent it back. Don't know why because the life expectency of his other 30 planes was less than a month, so whats the point of returning the plane. I off stab is the least of his problems

When I set it flat and measure it is about .25 inch difference one side to the other. I took a pic but you cant see the difference in it.

Try heating the epoxy with your heat gun or hair dryer while applying pressure to the stab until it is where you want it. Be carefull not to melt the covering.

Oh, I have flown several like this. Don't worry that much about it. While it won't have the precision of a pattern plane it will fly just fine.

I'd agree with the 2 above posts...

If it's 1/4" difference on a stab that size, it's enough to impact the plane's tracking and level flight, but not enough you can't trim it out. My own super stick is off by that much, and it flies fine with just a touch of trim.

Also, as suggested above, heating the epoxy and using some weight or clamps to pull the stab back where you want it might remove some of the problem.

I would shim up one side of the saddle for the wing and get them close if they are to far off.

Think of it like this. Every time you pull back on the stick, it's gonna try to turn towards the low side of your stab. Look, it won't take but a few minutes. Be very careful and cut if off and retry.
BTW, you can't trim this problem out. It only happens when you pull back on the stick.

I have a number of airplanes that are bent and crooked and they mostly fly just fine. By the time your skills are sufficient to recognize the miniscule flying differences you will also have another airplane. Trimming and adjusting a bent airframe, which I have been doing for years, can be a great learning experience. You don’t know the expiration date so just fly it.

Bill

It CAN'T be trimmed out. Twostroke's idea is the easiest. One way to check the severity of the problem is to look down the airplane from the tail end and eyeball the horizontal stab and the wing. If it looks "off" then fix it. Anybody that tells you to go ahead and fly it is just plain out giving bad advice. When you're a beginner, you need every advantage. A clean flying airplane is a big advantage.

ptulmer,

Would you explain, please, how the aerodynamic forces involved here only impact the plane when up elevator is given?

When it's tilted one side will create slightly more lift(can be trimmed, creates drag) but, when the elevator is deflected, if it's not lined up with the wing it pushed the tail out of the line of flight. (yaw)
If it's effecting straight line flight, it's either seriously out of whack or it's not straight with the thrustline. (incidence)

Thanks for the explanation, ptulmer. That makes sense.

I believe what happened is this: I thought you were saying there would be no impact UNTIL up elevator, but what in fact you're pointing out is that, prior to up elevator, any impact would be (for the most part) seen in the roll axis (which could be trimmed), but once up elevator is applied (and only at that time), the impact will be seen on both roll and yaw axes, which could not be trimmed since trim affects the plane in all flight conditions.

FWIW (not much, I know ) I agree...and I was unclear as well when suggesting it could be 'trimmed out'. I should have been more correct and suggested that issues could be 'mixed' out. As you say, any minor roll effect in straight line flight COULD be trimmed (though, again in agreement with you, if it's noticably out of whack in straight line flight, that's a pretty big issue). The induced yaw could be MIXED out by adding a touch of opposite rudder in with up elevator...something not unusual, given that many pilots do this to reduce the impact of torque and/or p-factor when pulling to an aggressive upline.

I still, however, submit that on a 40 sized plane, a 1/4" difference (if, truly, the angle is that small) will probably be insignificant in all but the most aggressive of flying conditions. In either case, were it MY plane, I'd be inclined to fly it a few times first before going through the annoyance of R&R that stab. (presuming, again, that the angle is as small as he suggests)

gb, your good use of the terminology leads me to suspect I was preaching to the choir...

A glance back shows me that he said 1/4" total, not each way. 1/8" per side ain't horrible. 1/4" per side would be. I ASSumed... Now I need to go pull my head out of my ASSumption.

LOL.

Nahh, you weren't preaching to the choir. Dad taught me a thing or two abot aerodynamics, but I'm not cocky enough (yet ) to presume I know EVERYTHING about them. Granted, HE did, but I doubt he taught it all to me.