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Manual elevator trim pictures

ijustwannafly

ijustwannafly

Well Known Member
Hey all, trying to decide between electric and manual trim.

Does anyone have any pictures of the manual elevator trim? I have not had a chance to see one in person and I'm curious how complex of a system it is. It is a cable like a throttle system? From the basic drawings i have seen it looks as though it is a vernier type cable of sorts.

Any pictures would be a big help.

Thanks!
 
Elevator Trim

Sorry, no pictures, but it's quite simple and works very well. A modest turn on the trim knob will set the trim. I was initially concerned about the tight turn of the cable in front of the fuel switch box (on the 7A), but that's a non-issue.
The cable does have a bit of slop in it, allowing for the trim tab to have about an 1/8" of free play. This was a significant concern with the FSDO inspector and initially he would NOT sign me off. I believe he did some research and upon his return a month later, it was no longer a deal breaker.
Hope this helps.

Jim Diehl 7A
Lock Haven, Pa.
 
jdiehl said:
The cable does have a bit of slop in it, allowing for the trim tab to have about an 1/8" of free play. This was a significant concern with the FSDO inspector and initially he would NOT sign me off. I believe he did some research and upon his return a month later, it was no longer a deal breaker.
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Click to expand...
This is my opinion as well. I love the manual trim--very easy to get precisely the amount of trim you want. It is a vernier cable and Van's instructs you to disable the center button to prevent rapid application of trim. However, the play in the trim tab for me is more along the lines of 1/4" and I wish it were not there, but when I asked Van's about it they said it was completely normal using that type of cable.
 
Thanks for the thoughts.

I was trying to decide between electric and manual trim. I originally was going to go electric but then decided i really wanted a mechanical solution. My concern initially was that it was going to be some sort of cable and pully setup. After finding out it is a simple vernier setup i did choose the manual. Im trying to build a light and simple airplane. I would assume no one has pictures of the manual because everyone has electric haha
 
I have manual and like it just fine. But it's in an 8 so the pictures won't help you much.
 
Unfortunately I don't have any pics either. It is a simple cable routing thru the tailcone to the left side HS and a cotter pin attachment to the trim tab horn. Mine has 1/8" free play max ... works wonderfully.
In flight trim adjustments require minute changes; at cruise speeds, 1/8 turn of the knob produces LOTS of trim change. I'm very happy with the manual trim and would repeat that decision if building another RV.
 
I love the manual trim but I didn't build my RV-8. It seems like it might have been easier to install and maintain electric trim in an RV-8 since the cable needs to route through the gear tower. Also, the manual trim cable is bulky and takes space.


click for bigger image
 
Manual elevator trim

I'm building a -7 and am planning on manual elevator trim. I do have about 10 hours PIC in an RV-9A with manual trim. The builder installed his manual trim knob in a console he installed between the seats. So the knob end of the trim cable pointed forward rather than toward the rear of the aircraft.

Not saying that's the best way, but it was part of his decision to do away with the pedestal below the panel and still have manual trim. I liked it and will probably do something similar on my -7. Seems like he "s-curved" the cable through the fuselage to take up the length, but I'd have to check with him to make sure.
 
Manual Pitch Trim

21+ years and still like it!
 
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Had electric but prefer manual

Had electric in the -10 and -8A ------- my -6A has manual ----- far more comfortable with the manual!
 
My -7 has manual. I am not flying yet so I cannot comment on how it works but I will say that it probably weighs more than the electric setup. Also I traded with Vans and got a cable for an -8 which is a little longer so the bend can be less severe.
 
ijustwannafly said:
Thanks for the thoughts.

I was trying to decide between electric and manual trim. I originally was going to go electric but then decided i really wanted a mechanical solution. My concern initially was that it was going to be some sort of cable and pully setup. After finding out it is a simple vernier setup i did choose the manual. Im trying to build a light and simple airplane. I would assume no one has pictures of the manual because everyone has electric haha
Click to expand...

Here is the manual trim control in my 1999 RV-6. The control in your RV-7 will be mounted to a small panel near the floor instead of the center console in the -6.

finish57.jpg


It is a very good system, intuitive to use and fool-proof. In 1300 hrs in the RV-6 I have never wished I had electric trim.

However.......if you intend to install an autopilot, some systems such as the Trio Pro Pilot have a nifty auto-trim system that will maintain trim via the electric trim servo. I fly the Pro Pilot and have never felt like auto-trim was a necessity but it is a nice feature.

Enjoy your project!
 
Awesome guys!

Thank you very much!

I did order my emp kit with the manual trim.

Cant wait for it to arrive! Thanks to all the replies!
 
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