What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

RV-3 LSA

n38139

Well Known Member
Any reason an RV3 can't be flown in an LSA category? I know they have carbon cubs with 180 engines that are LSA.
 
New build, or pre-existing? If it's ever had op lims that allow weights, operation outside of light sport parameters, then no.

New build, with weights/limits within light sport parameters...well, there's precedent......

Charlie
 
Rv3. LSA

In Australia we have three rv3's registered as LSA's. we do not have a restriction on max airspeed. We have a restriction on max take off weight and a minimum stall speed which the rv3 fits

Steve Lenne

RV3 completed and flying. Registered lsa.
 
The LSA limitations have nothing to do with HP but everything thing to do with gross weight, stall speed, speed at sea level with max continuous power, and more.

You will have to work hard to slow an RV-3 down. Limiting max continuous power is one way and may be a questionable solution.
 
In Australia we have three rv3's registered as LSA's. we do not have a restriction on max airspeed. We have a restriction on max take off weight and a minimum stall speed which the rv3 fits

Steve Lenne

RV3 completed and flying. Registered lsa.

You operate under different rules than we do in the States.
 
I'd suspect if it's a new build and you used a 2x4 for a prop, you may be able to achive LSA status. I've seen where some RV 9's were claimed/registered as LSA's so it's possible. The Panther is pretty much a copy of the -3 and several of them are registered as LSA.
 
Come on, guys; look at the Carbon Cub LSA & experimental versions. Do you really believe that the exp version won't go faster than 138 at full throttle with a 180 HP engine? It's the same plane as the LSA version.

Charlie
 
It is doable if you can get the stall speed slow enough. An 18 inch extension on each wing will give the stall speed needed. You will also need to alter the HS for control.
Install an 80hp whatever, or use an O320 and a 54 pitch prop. Limit rpm to 2700. Climb out will be impressive and top speed will be 138mph (120kts). But it must be done form the getgo.... iow.. first flight.
 
Any reason an RV3 can't be flown in an LSA category? I know they have carbon cubs with 180 engines that are LSA.


The answer to your question is yes - becasue of the stall speed. Of course, you can lengthen the wing, but that will take some design work and compromise other parts of the design. Limiting speed will make it far less of an all-around fun machine.

IMHO, there are better choices for a single seat LSA, ones that were designed for that purpose. The Panther LSA has been mentioned - nice airplane, designed to fit the specs. I flew the One-X last week, another good choice. The Merlin is a different animal (high wing, more STOL-ish), but lots of fun. And there are others I have flown (Hummel H-5, BD-17L....) that were designed to fit the category. Many are far easier to build than a -3.

If you are trying to use a currently flying -3 as an LSA, that's probably a non-starter due to the regs. If you are looking to build a single seat LSA from the start - I'd look at some of the other designs....

Paul
 
Come on, guys; look at the Carbon Cub LSA & experimental versions. Do you really believe that the exp version won't go faster than 138 at full throttle with a 180 HP engine? It's the same plane as the LSA version.

Charlie

Yes. The Xcub, their newest and redesigned to be fastest, doesn't exceed it by much. They are very draggy airplanes.
 
LSA Parameters Origin?

The LSA limitations have nothing to do with HP but everything thing to do with gross weight, stall speed, speed at sea level with max continuous power, and more.

You will have to work hard to slow an RV-3 down. Limiting max continuous power is one way and may be a questionable solution.


The rumor from FAA employees when the LSA rules were drafted was that the guys coming up w/the numbers had Ercoupe's, so the performance of that a/c became the poster child for LSA max performance.

Doug Lomheim
RV-9A Mazda 13B/FWF
 
The rumor from FAA employees when the LSA rules were drafted was that the guys coming up w/the numbers had Ercoupe's, so the performance of that a/c became the poster child for LSA max performance.

Doug Lomheim
RV-9A Mazda 13B/FWF

Actually, the LSA parameters came by copying the specs for a similar category in Europe - the funny English units convert to nice round metric numbers for weight, for instance. I can never keep the various European categories straight, but that's where they came from - because there were lots of those airplanes in production at the time..
 
LSA 3B

For the last 10 years I have been building a 3B LSA. C85, cruise/climb prop, no wheel pants and LIGHT. I worked with the late Marty Hollman to get the function and he gave me a function to work with. Using above parameters it fits the rule. The mods have added years. Also the custom slider I built was difficult. I have loved the challenge. Getting close


Bob Grigsby
J3 Cub flying
Dues plus paid
 
For the last 10 years I have been building a 3B LSA. C85, cruise/climb prop, no wheel pants and LIGHT. I worked with the late Marty Hollman to get the function and he gave me a function to work with. Using above parameters it fits the rule. The mods have added years. Also the custom slider I built was difficult. I have loved the challenge. Getting close.

So how are you going to meet the stall speed requirement?
 
Stall speed

I met the LSA requirement by building wingtips patterned from a Wittman W-10 Tailwind. They are 29" in length and are amazingly effective. The stall break is sharp but straight ahead. So far I have 10+ hours of testing so far.

Bill Newkirk
 
N38139

If you have to build it as an LSA as someone said then how do Ercoupes, Champs, and Cubs, all certified airplanes meet the requirements? I get the speed, weight issues.
 
If you have to build it as an LSA as someone said then how do Ercoupes, Champs, and Cubs, all certified airplanes meet the requirements? I get the speed, weight issues.

By being originally certified with performance & weight specs that fall within the requirements, and never having their type cert modified to exceed them. Some Ercoupes never qualified, and others have STC mods that take them out of limits. Once out, they can't go back.
 
Good point. But if built light, and the initial gross weight is set a few knots slower, it shouldn't be too difficult to meet the no flaps stall number. Anyone have a good idea on how many knots the -3's flaps are good for?

Charlie
 
Good point. But if built light, and the initial gross weight is set a few knots slower, it shouldn't be too difficult to meet the no flaps stall number. Anyone have a good idea on how many knots the -3's flaps are good for?

Charlie

I have never weighed anything in knots....:eek: but, maybe you are onto something.....
 
Back
Top