IowaRV9Dreamer

IowaRV9Dreamer

Well Known Member
I think I've been bit by the dreaded "pushrod too short" problem....:mad:

I'm talking about the control column to pitch pushrod, the one under the floor. After a bunch of reading and worrying I built it to plans length.

Now it is installed, and if I max it's length out, I can get the sticks to about 86 or 87 degrees, not quite 90. Doesn't sound like much, but that difference results in the stick end being about 1" forward of where it would be at 90 degrees.

Where in the manual does it say the sticks should be 90 degrees? Should they be?

If the answer is yes, I'll be ordering a new pushrod, making it 1/2" longer than the old one.

Thanks for any info,
 
The stick can be any angle you want as long as you have full travel. I have mine adjusted as far forward as it will go.
 
The plans don't show them vertical. See DWG 32, the one that shows the control systems. It doesn't give a precise angle but you can get it close. I assumed that was the neutral position when I put my short elev. pushrod in.
 
2 pushrods for me

I built a second pushrod (longer) for mine. My concern was having more than half the threads engaged at both ends so it can't come out unless I want it to.

Andy
 
Hi Dave,

Do you have your seats finished? Do you have your seat cushions yet--or do you have access to a set of cushions similar to the ones you will have?

I did this to determine correct stick position--and btw, I was also concerned about the push/pull tube being too short:

I installed the seats and a set of cushions from a friends RV6a (thanks Mr. Hurd), sat in the plane making airplane noises, let my left arm rest across my left thigh, and noted the position of my thumb/index finger on the left hand. I adjusted fore/aft position of the stick so that the stick base was between the thumb and index. Then we made sure full deflection does not hit the panel nor the family valuables. In my case the perfect position ended up being slightly forward of vertical--which provided adequate rod end thread engagement. Flying RV friends told me that on cross country flights you end up flying the plane with the thumb/index fingers of your left hand at the base of the stick--in my case they were right and the positioning is very comfortable.

Hope this helps.

Cheers,

db
 
Not supposed to be vertical !

The sticks are designed to be canted forward at 5 degrees, IIRC. I had the same problem as you and called Vans. Gus set me straight. Once you know the intended forward cant angle, you'll find the p-rod length is dead-on. :D

Terry
 
Sticks are not vertical

Like Terry said...they are not supposed to be vertical. Check the drawings and you'll see that the bottom portion of the stick weldment near the pivot point is at an angle to the stick. This part of the weldment is supposed to be vertical.

The stick itself will then be leaning forward.
 
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I had the same question on my -7. If I remember correctly the drawings have the stick centered over the center section. That's what I did.
 
Yep, it's your call.......

..as far as comfort is concerned, as long as the minimum threads are complied with. Besides, you can bend the stick as well.

Regards,
 
stick position

good point about the cushions and seating position being more important.
I have my seat all the way forward, just to reach the pedals, and I'm 5' 11" !
thus the stick is right in my crotch...and to cap it off, it only clears the throttle by 1/4".
I think you can learn to fly with the stick hanging from the roof.....but ergonomically, get some cushions and see how it all feels, and travel ( throws) etc.
Planning for a fancy grip like the Infinity?....nows the time to cut and wire that stick!
 
Sit in the plane, place your left hand on your upper thigh, then see where your hand rests. In my case the optimal angle to hold onto the stick is not vertical but slanted forward a small amount.
 
Don't know if the -9 is different from the -7, but with the stick rigged vertical (neutral) in a -7 the lower arm will contact the spar carry-through before you get full up elevator.

I don't know the drawing number, but the cutaway drawing that shows the entire fuselage side with controls in neutral position shows the lower arm of the stick vertical and the upper part leaning forward. From a control geometry standpoint that makes the most sense to me.
 
stick not designed to be vertical

Thanks to all... but Dave Cole wins the prize!!!*
I got the following back from Ken at Vans:
It's the tube on the bottom of the control column you want to be vertical, not the stick.

As with everything experimental, there is certainly wiggle room, and the builder is free to do what he wants, but I'm glad to know the design intent and will start from there. Best part is I don't need to order a new pushrod!:D


*no actual prize will be awarded.
 
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