New wings for Old-3

I am considering building 3-b wings for my RV. I have the old wing without CN-1 and CN-2 mods. Have considered doing the mods, but I am thinking building new with the b-spars may be lighter than fixing my a-wings, and then I would get the benefit of wing tanks. Having 22 gallons of fuel right above my knees has never been a favorite thing to dwell on either. I could always make a smaller header tank for cross country flight when I have it apart.
Questions:
How many hours (from those who know) to build a set of wings with tanks?
How difficult will it be to fit up the new wings to the existing structure?

Mine is a very nice build, quality work, and I know it has been flown to over 6g's. But having it updated is very appealing to me, and it may be the right time to do the project.
Any input form you guys would be appreciated.
Dave

Dave I have logged 616 hours for building my 3B wings. They are complete with everything done (except paint), this includes fitting of a roll servo, Dynon pitot/AOA tubing & Pulsar EXP tip lights. I constructed a side by side jig and built both wings simultaneously.
Russell

Center Section Fit

Dave -

I think getting "new" wings to mate to your spar bulkhead will be you biggest challenge. The airplane that Gary built all those many years ago probably doesn't have more than two holes in a row that match the plans - that's just the way it was back then - and to some degree, the same is true today of the -3 construction. Except for the spars & spar bulkhead - CNC precision drilled for both, insuring interchangeability among production runs. You would, more than likely, need to change out the F-303 bulkhead in order to match the spar splice holes in the new wings. Trust me, just having finished a set of wings and the fuselage - that would be a huge job with all of the attaching parts and pieces already in place.

Just my two cents worth - YMMV.

David Howe

I think HFS is correct. I've heard that before.

If wing tanks where the main reason to change, I would at the very least research what it would take to put wing tanks in your A wings along with the mods. It may or may not be less work overall.
I also believe, but nobody at Van's or elsewhere could verify, the 3B wing is heavier than the A wing even after tanks and mods. This is just an assumption based on my experience dealing with both types of spar designs. When I was doing the research, I couldn't find anybody who knew.

Would it be possible to obtain new type blank spars and splice plates then match drill/ream them to the original spar hole spacings to fit the bulkhead as is? So long as thickness and depth of the new spar is not larger than the original it could be possible? The new wings would then be built from critical measurements taken from the old wings and existing fuselage. QB wings probably wouldnt be suitable.

Retrofitting B wings to an RV-3 requires removing the existing center section bulkhead from the fuselage and installing a new one.

Building entirely new "A" wings to go into the existing center section is possible but probably not worth the effort, and getting an exact match of all the bolt holes to the center section would be a huge challenge (these holes were builder drilled and often are not exactly perpendicular to the bulkhead).
it would make more sense to upgrade the existing wings like Jon suggested.
Weight difference? I think you are right Jon, no one likely knows exactly, but if the B wing is heavier my guess would be that it wasn't by very much. Certainly not enough that it would be a factor for me in choosing one over the other.

dacronwall said:

Mine is a very nice build, quality work, and I know it has been flown to over 6g's. But having it updated is very appealing to me, and it may be the right time to do the project.
Any input form you guys would be appreciated.
Dave

Click to expand...

Why don't you look for a partially built RV-3B project that's pretty far along, then sell your current 3 when the new one is close to flying (i.e. to buy avionics & engine in the new bird)?

Thanks for the replies

I had a little "come-to-Jesus" moment today, and considering the advice of those who posted and friends I have spoken to, I think its better to just do CN-1 and CN-2 mods on my wings and be done with it.
All the opinions seem to indicate that bulkheads and carry over sections will have to be removed at tremendous effort, and I still will likely have problems fitting the wings up to my fuse.
My plane flies well, and with the mods, I will be assured of the safety for what looks to be less time and expense, while preserving the good flying characteristics and keeping the value in the plane for eventual resale.

I guess I will keep flying her through the summer, and look to remove the wings in the fall to rack them and start doing the spar mods. Thanks again for all the advice.
Best
Dave

Final decision

That sounds like a good plan, and will also give you an opportunity to check out the workmanship of the original builder while inside the wings.

Fly safe,

Doug Lomheim

RV-9A Mazda 13B/FWF
RV-3A sold