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Original RV-7 Rudder Dimensions.

mfleming

Well Known Member
Patron
Does anyone know the dimensions of the original smaller -7 rudder?
Also, is it still available?
 
Yes, and Yes - it is the same as current 8 rudder. You will need the 8 VS tip fairing, and both upper and lower fiberglass for the (8) rudder. Both rudders use the same counterweight. You will need the original 7 rudder stop dimensions.

I'll update with my post on dimensions.

See Bob Mills post on his rudder mods - it is the 8 rudder. https://vansairforce.net/community/showpost.php?p=658223&postcount=27
 
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Yes, and Yes - it is the same as current 8 rudder. You will need the 8 VS tip fairing, and both upper and lower fiberglass for the (8) rudder. Both rudders use the same counterweight. You will need the original 7 rudder stop dimensions.

I'll update with my post on dimensions.

See Bob Mills post on his rudder mods - it is the 8 rudder. https://vansairforce.net/community/showpost.php?p=658223&postcount=27

Thanks for that
icon14.gif
 
I'm also very interested in hearing from builders that have kept the original -7/7A rudder or added the -8/8A to their -7/7A.
 
I'm also very interested in hearing from builders that have kept the original -7/7A rudder or added the -8/8A to their -7/7A.

There is a recent thread where Walt and others talked about this.

Also, Matt, IIRC, verified that the RV14 rudder is the same and fitted it to his 7. The 14 rudder has a different internal design making it more torsionally stiff, like rvmills mods.
 
I'm also very interested in hearing from builders that have kept the original -7/7A rudder or added the -8/8A to their -7/7A.

I've done this on both of my RV-7s (Tailwheel equipped).

The first time was at ~250 hours after the original -7/-9 rudder developed a cracks along the trailing edge in front of a wedge stiffener that I had added early on. The difference, as others have noted, was very pleasant - like power steering; I suppose 20% less wetted area will have that effect. Crosswind landings (i.e. ~15kts) are no big deal, no issue keeping it out of the weeds.
 
There is a recent thread where Walt and others talked about this.

Also, Matt, IIRC, verified that the RV14 rudder is the same and fitted it to his 7. The 14 rudder has a different internal design making it more torsionally stiff, like rvmills mods.

The -14/14A rudder is, I think, the same size as the newer -7/7A rudder. This may be OK but the Van's Service Bulletin implies that original -7/7A rudder is approved as well as the newer/larger -7/7A rudder. I'm looking to downsize to the original rudder.

I've done this on both of my RV-7s (Tailwheel equipped).

The first time was at ~250 hours after the original -7/-9 rudder developed a cracks along the trailing edge in front of a wedge stiffener that I had added early on. The difference, as others have noted, was very pleasant - like power steering; I suppose 20% less wetted area will have that effect. Crosswind landings (i.e. ~15kts) are no big deal, no issue keeping it out of the weeds.

Sounds great... I'm looking for flutter margins that match the rest of the Van's fleet.
 
I'd like to know if the newer -7/7A rudder (from the RV-9) has wider chord than the early -7/7A rudder (from the RV-8) or if it is just the taller tip cap and counterweight area?

And by extension, does the RV-14 rudder have a wider chord than an RV-8 rudder? Or are they the same except for the taller tip cap and counterweight?

Ultimately, what I would like to do is use the RV-14 internal stiffener system on an RV-8 rudder with folded 0.020" skin.
 
I'd like to know if the newer -7/7A rudder (from the RV-9) has wider chord than the early -7/7A rudder (from the RV-8) or if it is just the taller tip cap and counterweight area?

And by extension, does the RV-14 rudder have a wider chord than an RV-8 rudder? Or are they the same except for the taller tip cap and counterweight?

Ultimately, what I would like to do is use the RV-14 internal stiffener system on an RV-8 rudder with folded 0.020" skin.

It has a wider chord -- I'll get the dimensions for you next time I'm out at the airport.
 
Just for comparison...

I'd like to see a dimensionally accurate overlay of these vertical stabs/rudders to see how they compare.
 
Here ya go. The counterweight is the same for both and in the same location relative to the pivot axis. Weight not including tips. CG measured, not calculated.


Screen Shot 2022-10-29 at 7.33.31 PM.png

Screen Shot 2022-10-29 at 7.33.40 PM.png
 
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Below is a pic of the -8 rudder on the left and the -9/-7 rudder on the right, sans fiberglass fairings. Thanks to "ArlingtonRV" for the samples.

i-KJZdmw5-XL.jpg
 
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