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RV-7/7A manual trim

Dave Taylor

Well Known Member
Does anyone have a cockpit photo of where the manual trim knob is installed on an RV-7/7A?

Thanks,

-David
 
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Trim

RV6A said:
Does anyone have a cockpit photo of where the manual trim knob is installed on an RV-7/7A?

Thanks,

-David

I am curious about this as well. After reading DR's post in which he suggests that manual trim might actually be better, I am considering it as well. Looking at the preview plans it appears that the knob is mounted near the floor, mid panel, slanted 45 degrees back towards the seats. Envision sitting in the pilots seat and extend your right hand down, slightly forward, and slightly to the right. Grab the knob and turn. If you prefer to fly with your right hand while adjusting trim with your left, I guess the control knob could be moved to the left side of the bulkhead somewhere. Or of course electric trim is always an option as well.

I can't find any reference to manual aileron trim in the preview plans. It may be there but I haven't found it yet. Maybe those drawings come with the trim kits. I imagine it is the same setup as the elevator trim and the knob will probably be mounted close to the same position as the elevator trim knob. This is just speculation on my part, I really don't know.

Hopefully, someone who has installed one or both of the manual systems can post some photos for us.
 
Manual Trim

I am a 6A builder but I am incorportating some of the changes made for the 7A. One of them is the placement of the manual trim. Originally the -6A had th knob mounted on a center column that went from the bottom edge of the instrument panel down to a mount for the fuel valve just infront of the spar. The 7A has the trim knob mounted on an extension of the fuel valve mount, thus eliminating the center column. I like the added sense of spaciousness it gives the cockpit.


I tried to upload an image of it, but I get a message that the file size is too large.(?) If you want, I can email it to you directly.

Regards,
 
painless said:
I tried to upload an image of it, but I get a message that the file size is too large.(?) If you want, I can email it to you directly.
QUOTE]

An image would be great. Uploads on this site are limited to jpgs and I am not sure of the file size but if you keep it under about 400x300 pixels with a quality of 7 or 8 it should be OK. If you can't get it to work you can send the image to me at [email protected]. Thanks!
 
Manual Trim

Tom Maxwell said:
I can't find any reference to manual aileron trim in the preview plans. It may be there but I haven't found it yet. Maybe those drawings come with the trim kits. I imagine it is the same setup as the elevator trim and the knob will probably be mounted close to the same position as the elevator trim knob. This is just speculation on my part, I really don't know.

Hopefully, someone who has installed one or both of the manual systems can post some photos for us.

Drawing 32A in the RV-7 preview plans shows the manual trim. I have been leaning toward electric trim. This discussion has gotten me to consider how I fly. I have been renting a 172S and a 172R. The "S" has electric trim as well as manual trim. The "R" has only manual trim. I find that I use the manual trim almost exclusively. Thanks guys for helping make another decision.

Zack Spivey
RV-7 preview plans
 
Best of Both Worlds

I've been considering how to install both electric and manual trim on my 7A. It looks to me like we might be able to combine the Vans manual trim system with the Gretz Aero http://gretzaero.com/ alternate electric trim mounting kit to provide both a manual and electric trim system. That's what I have in my current ride (mooney) and I like the idea of being able to override a failed electric trim system. I'm considering mounting the servo in the gretz installation on a sliding track that is controlled by the Vans manual trim cable. That way, we could have both manual and electric trim.

Comments??

Terry Frazier
7A Emp
 
Re: manual vs. electric
All my planes prior to the RV-7A had manual trim. A rental I flew had electric and manual, but because I was comfortable with manual I never could get into the habit of using the electric trim.

On my 7A I installed electric and I'm quite happy with how it turned out - by the end of the second flight it seemed totally natural. I recently was given the keys to a 6A to fly around for a bit. It had manual trim in the same location as the 7A plans, and it wasn't nearly as handy as having the trim switch on the stick.

I'd say, don't bother with trying to have electric and manual. If you have 'em both I'd bet that you only use the electric. ;)
 
Here is a shot of my trim cable installation. This is Van's standard installation. The cable is mounted in the fuel selector mounting plate and the cable doubles back thru the center section back to the tail. I like the manual trim and find it simple and easy to adjust.

Roberta

trim28hz.jpg
 
Well Maybe Not

I owned a plane for 22 years that had both and I almost never used the electric. For the first seven years of its life I leased it to the McDonnell Douglas Flying Club however, and the electric system did fail (not in the runaway -shorted- mode thank goodness) requiring irregular maintenance to avoid having inoperative systems in the airplane. Mine is an RV-6A but the basic configuration is similar. The console angular panel was determined by the angle of the doubled back trim cable. It also contains two fuel valves down on the flat panel and the aux. fuel pump toggle (not installed at the time this photo was taken) and Primer push button switches on the vertical. Inside are four fuel filters (metal), the aux. fuel pump, the primer solenoid valve, all of the interconnect hoses & wiring, and all of the wires and coaxes that route aft of the main spar go through there. The pitch trim falls naturally to hand with no hunting or reaching.

Bob Axsom
trimpos9af.jpg
 
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