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RV-8 style gear for RV-3?

AndrewBS

Member
Has anyone put an RV-3 on an RV-8-style spring-leaf main gear?

I know it would require the design/fab of a gear box, but would it be worthwhile? I'm building an RV-3 from scratch using 'legacy' plans (from the 70s, and yes, the B-wing mods are included), and have been thinking along these lines for a better gear or rougher fields.

Many thanks in advance for y'all's thoughts.
 
Why do you think it?s better?

The gear mounting location is drastically different. Motor mount vs fuselage mount. I would think it might impact your cg dramatically. It would require a lot of re-engineering. I don?t understand what there is to gain.

The one and only (minor) dislike I have about the 8 tailwheel is the location of the gear. It looks a bit awkward compared to other models. It just isn?t as balanced in appearance. It still looks ok on the 8 with its long fuselage, but the stubby 3 might not sport it well.
 
Can't address the -3's ruggedness, but the -4 is pretty tough. If you want really tough, why not see if the guys who make the Rocket gear would make you a set. IIRC, it's a titanium leg. You could get a longer gear in the bargain, if you have the mount's socket angles adjusted to keep the axles in the right place.

I'm not a fan of the -8 gear, either. Appearance is largely personal taste, but ask an -8 owner how much he enjoys checking those mount bolts at annual. At least some of the -8 owners I know consider the gear far less forgiving than the Whitman style gear on the other models. Then there's the intrusion into your 'personal space' in the cockpit. :)

Last, I'd think that tweaking the stock design would be a lot more 'do-able' than such a radical change in all the load paths.

Charlie
 
I agree with JonJ. The RV3 gear looks better, as do all engine mount based tapered rod RV taildraggers. Not only that, it is a better system I terms of maintenance and landing manners - in my humble opinion. I just finished an annual on my friends (JT) RV8 and had to torque those outer saddle clamps bolts from H_LL. The front ones were easy, relatively, but the aft ones took me almost 2 hours. This is a design flaw in my opinion. On my RV8, I’ve installed Bruce B’s bolt head clips that capture the bolt head in the landing gear tower weldment, with the bolt installed from the top down. I also installed them on my first RV8 after experiencing the agony of torquing these nasty nuts 3 times before making this easy mod. The clip holds the bolt head from turning, so all you have to do is torque the nuts from the bottom, as it should be. It takes me about 60 seconds to torque all four of these on my airplane. The bolt and nut is completely hidden by the upper intersection fairing - I have the Fairings, Etc fairings.

Sorry for the rant, but I think the designed landing gear for the RV3 (4,6,7,9) is fine as it is, and it looks better to boot.
 
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Steve,
I?ll tell Bruce there?s an interest for some more. He?s sold several and he can spool up the machine to make more if there?s interest, so I?ll connect him to this post and he will get in touch. They work great. You have to pull the bolts out to insert them from the other direction and this can be done just sitting on the ground - try not to move the plane, and do them one at a time. You may have to ?coax? the bolts out/in and I did that with a rivet gun and an offset driver set on the lowest pressure setting to just sort of ?thump? on them to get them into position. As you insert them from the top you may need to stop just short of engagement with the clip and use a 9/16 wrench to align the flats before pushing it home. Trust me, this is the last time you will ever have to get in that gear tower other than to look in there with an inspection mirror during your condition inspection to look for lost stuff. It?s taken the gear tower off my hit list for airplane design.
 
Ok, so a new gear tower structure for an RV-3 would put the nuts on the bottom. There, fixed.

No more bent firewalls. No more cracked mount tubes. No more wheels that wobble and wiggle and shimmy and shake.

Devil's advocate, over and out. ;)
 
What about gear shimmy with the stock tapered gear arrangement though? That was a constant problem with my -3. I think the Grove Gear would be a considerable improvement in regards to shimmy. Should also be gun-drilled, which eliminates the need for external brake lines. Those are two big improvements in my mind.
 
Ok, so a new gear tower structure for an RV-3 would put the nuts on the bottom. There, fixed...

But if the -3 is like the -4 and Rocket and features the central keel, then you are going to have almost no room for your feet once you add the -8 gear towers. At least the -8 has the center of the floor free and its still intrusive.
 
But if the -3 is like the -4 and Rocket and features the central keel, then you are going to have almost no room for your feet once you add the -8 gear towers. At least the -8 has the center of the floor free and its still intrusive.

So switch to one-piece gear, requiring outboard structure only.
 
Certainly an option. My neighbor had an RV-4 converted to a nosewheel and it featured a Grove style spring gear for the mains. Worked just fine.
 
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Background: built/flew an RV-8 for 400 hours, then built/flew an RV-3B for 300 hours. Based on that experience I much prefer the RV-3/4 rod landing gear. Somehow it feels better, is more forgiving, and frankly I like the swept back looks as well.

The structure required in the fuselage for -8 style gear would be considerable and I can't imagine how it could be retrofitted with proper strength integrity without a boatload of heavy structure.

FWIW.
 
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I agree with the 'Rod Gear' crowd. I built an RV-8, my wife has an RV-4. I fly them both.
I wish my RV-8 had the rod gear, the landing and ground handling are better, and I could "MAN SPREAD" in comfort on those long flights..:rolleyes: without those gear towers taking up leg room and generally being in the way when I work around the consoles and panel. :(
 
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