Elevator trim tab question

[vic syracuse]

Hello everyone. My opinion is that the trim tab set up is just fine. I just turned 480 hours on the RV-10 this past week end, and I think during that time I have seen most every kind of loading, speed, and altitude scenario. I have not noticed any issues with the trim at all. That doesn't mean someone hasn't/won't design a better system, as that's what this Experimenting is all about. But, at this point in time, I don't see that there is anything to fix.

Vic

[Reddsky1]

I ain't no engineer, but my friends at Rockwell are.

The trim tabs should not be asymetrical in their travel limits.

It may not cause noticable abnormal flying conditions, but it does cause asymetrical stresses to the Horizontal Stab. and elevators.

Take it for what it is worth, my 2 cents.

Reddsky1

Building (SB) RV-10 wings

[Mel]

Originally Posted by Reddsky1

I ain't no engineer, but my friends at Rockwell are.

The trim tabs should not be asymetrical in their travel limits.

It may not cause noticable abnormal flying conditions, but it does cause asymetrical stresses to the Horizontal Stab. and elevators.

Take it for what it is worth, my 2 cents.

Reddsky1

Building (SB) RV-10 wings

If this is the case, then almost all GA airplanes are in trouble, as they almost all have a trim tab on one side only.

[dmaib]

I believe the assymetrical stress was what Bill DeRouchey witnessed on his airplane, in flight, when he looked back at the horizontal stab. Makes sense to me.

[dmaib]

How about asymetrical. I miss my spell checker

[hugo]

I had the oportunity of fly the 10 for a couple of hours,and the first fly things you learn is ,don't touch that trim until you are high ,let me tell you guys ,that trim is very ,VERY sensitive,I beat you don't move more then a 1/4 inch at all,when discuss with Van's ,the reason for the assymetrical travel,and make sense to me ,was,because the 10 is nose heavy,you don't need to much down trim ,but need much more nose up,I purchase the speed reduction from Ray Allen,
And another system I changed after that fly ,was the position for the front air vents,if you are in the 6' tall range ,and you open the front vents,your knees will be very mad with you,they will frezze.
Hugo,#40456

[ScottSchmidt]

Your right it is asymmetric when you are at the complete limit because of the way it is designed. But you never even get close to those limits. You probably will go from ?? up on one side to ?? up on the other side depending on your loading in the aircraft.

It is very sensitive when you are at cruise flight but not too bad. It is just the right speed when you are landing. I have a speed controller but see no reason to install it.

[tnelson]

Though it doesn't seem to be an issue for most, I had some time on my hands and started looking at the trim rig laying on my bench. Seems like a simple solution, but I wanted to see if anyone could lend an engineering eye to my idea. I built a new cable anchor (1st pic) that allows both to be mounted side by side, which is simple enough. Question 1 is with where the rod ends attach to the bellcrank. Will the 3/16" bolt through both rod ends be adequate for the load? The bolt in the 3rd pic is not correct length, but it shows the attach geometry. Next, might there be leverage issues with having the load from both cables going to the front hole on the bellcrank?







Thanks for looking