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RV-4 wing to F1/F4 configuration

Freemasm

Well Known Member
I have a set of RV-4 wings completed to ~ quick build stage. The end product goal is a 210 HP F4. I?m currently ordering/soon building 42 gallon tanks then moving WW ribs to meet new interface points. Any advice/references/etc out there from someone who?s done this would be appreciated.

Much thanks,
Scott F
 
Can you be more clear on your "configuration"? Rocket wings are shorter span and have tighter rib spacing than RV-4 wings. Do you intend to keep the "long wing" of the -4, but with bigger tanks and the inboard area matching the Rocket fuselage?
 
Clarification

Thought it was clearer than it is. The wings are at QB stage so they will essentially be RV-4 wings Mod?d with larger tanks for the larger engine and to meet the different (forward) IF points.
 
I would use standard length wings

I'm at the canopy stage of my F4 project. Wings are the shorter F1 version. But, talking with Mark Fredrick (sic?) about the lower hp F4, he says more wing area is desirable. The F4 will have at least 50hp less than the 6 cylinder version. This, I'm told, will effect the performance of the shorter wing at higher altitudes, making the standard wing more efficient when flying up high.

Maybe someone here wirh aeronautical engineering training knows how to describe this more clealy than i have here?
 
The longer wings will be better at altitude, research parasitic drag vs. Induced drag. The downside, and for me a major factor, is that those longer wings can not be used with the larger engine. This gives your aircraft fewer sales opportunities in the future.
 
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If they are built up as RV4 wings they will not work on the rocket. The rocket fuselage is wider than the RV4. The spars will not meet in the middle. If I am misunderstanding and you have built them to fit fit the rocket disregard.
Ryan
 
A good friend of mine built a HR2 in the early 90's. It has standard RV-4 wings and a a center section was fabricated with longer splice plates and a stub spar the middle. Never had issues. The airplane is still flying. A new center section was fabricated using the original RV-4 center section as a pattern.
 
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Lots of configurations will work

Best of my knowledge here; The HR2 wings are RV-4 wings with "restationed" ribs (and some other changes). It's not just a strength issue/concern but to stiffen/avoid aero flutter at the higher speeds. The F1 Rocket folks were kind enough to give me some drawings to convert the wings for the F1/F4 fuselage. There's plenty of documentation for converting the center section. The root area of each wing has to be mod'd to ensure the proper interface. Just wondering if anyone had done that versus building from scratch.

Vertical penetration aside, the performance numbers between the 4 and six cylinder aren't as different as you'd think. As I've seen established rocketeers convert back to a four banger and the owner of F1 aircraft state he's building a 4 banger (has owned a six cylinder version in the past) it wasn't that hard of a decision. The F1 aircraft site is a world of good info. Some have used very stock RV-8 tails/wings as well. Lots of choices.

Anyway. I'll say again. If anyone has performed a "mod" of existing RV-4 wings and can share any good advice, it would be greatly appreciated.
 
Winging it...

I have a set of RV-4 wings completed to ~ quick build stage. The end product goal is a 210 HP F4. I’m currently ordering/soon building 42 gallon tanks then moving WW ribs to meet new interface points. Any advice/references/etc out there from someone who’s done this would be appreciated.

Much thanks,
Scott F

Scott,
I've owned and rebuilt a early HR2, built a 4 and installed a set of modified RV4 wings on an RV6 fuselage.(I call it the RVX) As so eloquently mentioned above, the RV4/6 HR2 wing ribs, skin and spar length are specific to the fuselage intended. The HR2 rib spacing is different for the aforementioned reasons above and many people (mine included) employ a 1 piece top skin.
The RV4 and RV6 wing are identical except for one inboard rib bay which I removed to allow the spar to match the RV6 spar box. I had already built the 4 fuel tanks and the wingspan matches, so the X is essentially a side by side RV4.

For you, I recommend staying the course with your wings, purchasing the HR2 fuselage skins and bulkheads and building a Fastback RV4. There are many threads on the site (hit search above) on the Fastback, Axel (AXO) probably posted every step of his build. Dave Anders highly modified FB4 is undoubtedly the fastest RV on earth.
You won't be disappointed...:)

V/R
Smokey
 
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Scott,

Smoky is assuming that you aren't after the F1/F4s much larger and more comfortable cockpit. I liked my RV-4 very much, but I loved my Rocket.

FWIW, about 1/2 of the new projects that we're involved with are opting for the 4 cylinder. And why not? Brad Hood has repeatedly told me that his 200+HP F4 is the finest flying plane he's ever flown.

We're just trying to make a few more options available. Browse the website for more info.
 
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