Late RV-6 empennage

[hohocc]

In the process of accumulating parts for my 6 project I've ended up with a spare, mostly completed late 6 empennage with the tall fin and rudder. At some stage I will want to part with these, can they only be used on a 6, or are they usable on a 7, or even 8/9? Obviously there will be more folks who may be able to use them if they are not only suitable for a 6, and it seems a bit of a waste if they never get used for anything.
Thanks.

 

[Inverted]

The late -6 tail is basically the same as the early -7 tail. Vans replaced the early -7 tail with the tail from the -8 due to issues with recovering from a spin. For that reason, I would say it is most useful on a -6. However, someone could put it on a -7 if they wanted...

I actually have a late -6 tail and an early -7 version and they are basically identical.

 

[sprint27c]

Elevator

If you're ever looking to part it out separately I could use the right elevator...would save me a bunch of time re-skinning...

 

[hohocc]

Thanks for the info inverted, one of the reasons I asked is I have a friend interested in building an 8 but it seems to not be a great starting point for him, better to know now though!
Sprint27c, at the moment I'm keeping it as a sort of reference item, but will be moving it at some point. It is however in Christchurch, New Zealand so there are probably easier options for you closer to home! Thanks for the interest though.

 

[rvbuilder2002]

The late -6 tail is basically the same as the early -7 tail. Vans replaced the early -7 tail with the tail from the -8 due to issues with recovering from a spin. For that reason, I would say it is most useful on a -6. However, someone could put it on a -7 if they wanted...

I actually have a late -6 tail and an early -7 version and they are basically identical.

You are partially correct. It is the same as the original RV-7 vertical stab. and rudder, which is the same as the RV-8 vertical stab and rudder.

When the 7 design was updated, only the rudder was changed (the vertical stab stayed the same). An RV-9 rudder was used in place of the RV-8 rudder.

To recap,
The late issue RV-6 emp. kits, RV-8, RV-7, and RV-9 all use the same vertical stab.
The late issue RV-6 emp. kit, and the RV-8 use the RV-8 rudder.
The RV-7 and RV-9 use the RV-9 rudder.

Disclaimer....One thing I can't remember is whether the skin thickness on the late issue RV-6 rudder and elevators was .016 or .020 thick. I am thinking it was .016 in which case they should not be used on an RV-8 or 7 even though they are structurally the same in all other respects.

 

[hohocc]

OK that sounds a bit more hopeful on the fin and rudder front, any info on the elevators and tailplane?
Appreciate the help, thanks.

 

[rvbuilder2002]

Disclaimer....One thing I can't remember is whether the skin thickness on the late issue RV-6 rudder and elevators was .016 or .020 thick. I am thinking it was .016 in which case they should not be used on an RV-8 or 7 even though they are structurally the same in all other respects.

OK that sounds a bit more hopeful on the fin and rudder front, any info on the elevators and tailplane?
Appreciate the help, thanks.

The elevators would be the same size and design as on the RV-7 and 8, but as posted above, I think the skin thicknesses are different
Substitutions of skin thickness should not be done on the 7 and 8. They have a higher VNE. VNE is at least in part related to structural stiffness. In semi monococ aluminum structures, stiffness is in part related to skin thickness.

 

[hohocc]

Ok I get that the skin thickness needs to be checked on the elevators and rudder, but otherwise they should be the same design as the 8, and that the fin should be the same as the 8. The one other item is the tailplane, is that 8 compatible also?
Thanks for the info.

 

[rvbuilder2002]

Ok I get that the skin thickness needs to be checked on the elevators and rudder, but otherwise they should be the same design as the 8, and that the fin should be the same as the 8. The one other item is the tailplane, is that 8 compatible also?
Thanks for the info.

The RV-8 has a narrower fuselage because of the tandem seating. This causes a different tapper angle on the tail cone, so the RV-6/7 horizontal stab. is not interchangeable with the 8. There are a lot of parts common between them (rear spar, some ribs, etc), but a lot of parts would have to be changed. The most significant ones being the skins.