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RV-4 LSA ?

SwoonCraft

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RV-4 "style" LSA petition please sign.

We the people of EAA and AOPA, in order to perform a more perfect union of aerodynamics and shoulder room, domestic tranquility, provide for the common LSA pilot, and secure the Blessings of the FAA to ourselves and our posterior, do humbly request you ordain and establish an RV-4 LSA for the unaltered states of flying nirvana.

Click this link if you would like to see an RV-4 "style" LSA:

http://www.ipetitions.com/petition/rv-4-style-lsa/
 
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Couldn't happen

The RV-4 is way too fast to ever be flown under sport pilot rules.
120kts max..... Maybe an old C-65 engine would work? :D
 
Have you seen the Lightning? Supposedly this is a redesigned airplane but it's bones look an awful lot like the Lancair 320. Just stick a serious climb FP prop on the nose :)
 
You've thought it. Admit it.

My original post was meant to be a fun way to continue the discussions of an RV-4 ?style? LSA. We the customer need to make sure that the demand is documented. If anyone has a better way to convince those in power that there is a demand for a RV-4 ?style? LSA; I'm all ears.

How many people have thought to themselves wouldn't it be great if Van came out with a new wing for the RV-4 that would make it sport pilot legal or maybe the new Lycoming IO-233-LSA would work? You've thought it. Admit it.
 
continuous power limitation?

I don't really keep up with LSA rules. But would it be possible to write in some continuous power limitations like Cub Crafters has done with the Super Sport Cub to keep cruise speed down? There is probably more to it than that...:eek:
 
I don't really keep up with LSA rules. But would it be possible to write in some continuous power limitations like Cub Crafters has done with the Super Sport Cub to keep cruise speed down? There is probably more to it than that...:eek:

CubCrafters had their engine manufacturer make up that continuous power limitation. As builder of your own engine, you could do the same, but if something happened and you ended up in court for some reason, I think you might have a difficult time with defense.
 
Have you seen the Lightning? Supposedly this is a redesigned airplane but it's bones look an awful lot like the Lancair 320. Just stick a serious climb FP prop on the nose :)

This seems to be one of the most misunderstood LSA perfomance requirements. The requirement is that the airplane meets the 120 kt max. speed requirement at max continous power, not max continous RPM. Because of this you must meet the speed requirement when operating at max contious RPM and a manifold pressure that at the RPM you are using, provides max rated continous power.
Putting a flatter prop on that requires a throttle reduction to stay within the engines RPM limit and the resultant limit in speed, does not meet the ASTM requirement for LSA

I don't really keep up with LSA rules. But would it be possible to write in some continuous power limitations like Cub Crafters has done with the Super Sport Cub to keep cruise speed down? There is probably more to it than that...:eek:

This is probably the only possible way to do it, but as Mel already metioned, I think anyone doing so is walking a very fine line. If an identical engine is also rated at a higher power output in another aircraft I would think the FAA will likely have some raised eyebrows eventually.
Over the years there have been different type certificated airplane models that have used different models of an engine with it rated (or derated) at different power outputs so maybe they are ok with it.
 
I'd buy it!

I have posted the same idea at least a couple times in the past. There is not a single LSA out there that gets my attention like an RV-4 style LSA would. I think that the O-233 would be a good fit and possibly help with W/B issues for the GIB.

Ironically this idea has been bouncing around my head more lately... and I had planned on posting something similar - but more based on a question of feasibility. For the engineers and armchair aircraft designers...

What are the possibilities or hindrances in this idea? Can a tandem, aerobatic, LSA specification aircraft be built in aluminum (meaning Van's of course) that would not weigh much more than the RV-12 - and thus allowing for 3 hours fuel (incl. reserves) and carry a couple 200 lb. passengers and 50 lbs. baggage. What say ye... can it be done?

dj
 
DJ, you nailed it when you said “There is not a single LSA out there that gets my attention like an RV-4 style LSA would.”
 
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It's clear there is an interest in this type of RV and so although this has been discussed in another thread in the past it's perhaps worth keeping this thread alive.

I am a Newbie and don't know how an RV goes together, but on the basis of weight and stall speed it appears that an RV4 with a longer nose, lighter powerplant (UL260, 912, Jab 3300) and larger wings (perhaps from another RV and available as a quicklbuild?), could be made to comply. The sticking point seems to be the speed under max. continous power. The idea of a flat prop or making it artificially draggy is so counterproductive. The origin of the problem seems to be the way the available power units are specified. It would appear one wants as much power as possible to enable you to get off in the shortest possible distance and at high density altitudes, but then to have a more modest continuous power spec for cruise. This is easily solved if you were to use an experimental engine, as you can then specify the max continous power. Furthermore, the philosphy of derating an existing engine is not out of whack with the LSA theme as it all helps to keep the operating costs down via lower fuel burn and longer TBO. In fact the speed limitation is a real impediment to developing really slippery, efficient LSAs to achieve low fuel burn during cruise, unless you can have an engine with this sort of reduced max. contiuous power rating, otherwise they will just blow through the speed limit.

The aircraft engine market is small and the market potential of a tandem RV LSA significant, so would it not be possible to approach one of the established companies and ask for them to build a special `RV4 LSA' variant that provided a maximum power for a few minutes and a lower continuously rated power? Perhaps they could offer it at a lower cost, or with a longer TBO as a result of this spec.?

mike
 
It's clear there is an interest in this type of RV and so although this has been discussed in another thread in the past it's perhaps worth keeping this thread alive.

I am a Newbie and don't know how an RV goes together, but on the basis of weight and stall speed it appears that an RV4 with a longer nose, lighter powerplant (UL260, 912, Jab 3300) and larger wings (perhaps from another RV and available as a quicklbuild?), could be made to comply.

Then it wouldn't be an RV-4. ;)
 
It's clear there is an interest in this type of RV and so although this has been discussed in another thread in the past it's perhaps worth keeping this thread alive.

I am a Newbie and don't know how an RV goes together, but on the basis of weight and stall speed it appears that an RV4 with a longer nose, lighter powerplant (UL260, 912, Jab 3300) and larger wings (perhaps from another RV and available as a quicklbuild?), could be made to comply.

mike

It could work with an RV3. Extend the tips 18" each and use 100 hp. Add drag to limit top speed...................Done deal.
 
You wouldn't need to add much wing. The stall speed would appear to be pretty close just by dropping the weight down. The lighter enigne would need to be shoved forwards a bit, but I dont really have a good idea as to how much - at a guess you could lose >100lbs off the installed engine weight.
So it wouldn't be an RV4 but it might not be miles off.

Lastly, it just seems nuts to add drag to limit the speed (and increase the fuel burn) - may as well have a biplane!
 
RV-4 "style" LSA

Then it wouldn't be an RV-4. ;)

You are correct it wouldn't be an RV-4 but it would be the highest evolution of the species LSA.

Read the whole thread and you will see that the intent was to request the engineering power house of Mr. Richard VanGrunsven design an RV-4 "style" LSA.
 
To make it work, you would have to build a RV4 that weighed 780#. This won't happen.

Does a tandem seat RV-12 have to weigh more than a side by side RV-12? Bet it will happen.

You can call it whatever you like: RV-4 LSA, RV-12 Tandem, RV-13. How about we start a new thread; "What is Van going to call the new tandem seat LSA?"
 
You are correct it wouldn't be an RV-4 but it would be the highest evolution of the species LSA.

Read the whole thread and you will see that the intent was to request the engineering power house of Mr. Richard VanGrunsven design an RV-4 "style" LSA.

I read the whole thread (I'm a forum moderator :) )

Does a tandem seat RV-12 have to weigh more than a side by side RV-12? Bet it will happen.

You can call it whatever you like: RV-4 LSA, RV-12 Tandem, RV-13. How about we start a new thread; "What is Van going to call the new tandem seat LSA?"

I have no idea if Vans will ever produce a tandem-seat LSA (wonder what kind of problems would arise with the necessity of a wide CG range on a light aircraft? Seems most tandem LSAs are pusher configurations.) but I suspect in keeping with the conservative and deliberate pace of product development the very well-received RV-12 will be the LSA focus at Vans for several years.
 
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Agreed, but if you don't ask....

There is a demand for all kinds of aircraft. If there wasn't Van would have stopped at the RV-3.

I believe that given enough time an RV-4 style LSA would out sell all other RV(s).

I also believe that Mr. VanGrunsven is a business man, but inside that business man heart lies the heart of a dreamer and a tinker. Who ells thinks I can make a better wing and then proceeds to rip the wings off their plane? Mr. VanGrunsven is one of those fortunate few that has found the job or more to the point created the job he would gladly do for free. That is why I believe we will one day see an RV-4 style LSA.
 
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New to the group and found this discussion interesting understanding the original post.

Goals for my homebuilt project: Capable of recreational aerobatics, two seater (tandem is better), all metal, fly under LSA rules, taildragger, useful load of 410 lbs or more, content to throttle back & fly @ best economy cruise.

I do not want get another medical and my flying will be local in North Carolina.

Can a flat prop be used with an 0-290 or 0-235 to meet the LSA Vh 120 Knot rule in the RV-4 retaining a decent climb rate?

Can a RV-4 with minimum instruments be built weighing 900 lbs?

It looks like the stall speed might be around 51 mph @ 1320 lbs in the RV-4.

Always admired Van's designs but have not flown one. Most of my time is in Cessna/Piper aircraft with J-3 time and aerobatics in the 100HP Cessna Aerobat.
 
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LSA -4

The Sonex with the 3300 jabb is SP,aerobatic, aluminum has 500 lbs usefull load 400 mile range and builds in half the time of a RV. It flies like a RV but heavier ailerons
It looks ...well differant, but is a heck of alot more like the RVs we all love than the -12? I guess you've figured out I built one. You can see it at www.flycleanex.com . the -9 always had me scratching my head then the -12 comes along, I aggree a LSA -4 Dan Weseman
 
danweseman;391915 I guess you've figured out I built one. You can see it at [url said:
www.flycleanex.com[/url] . the -9 always had me scratching my head then the -12 comes along, I aggree a LSA -4 Dan Weseman
That link doesn't work for me. Is it supposed to be the Sonex site? www.flysonex.com
 
Hmm My website is down now for some reason try again later? Dan

Dan,

Googled flycleanex.com and came up with this video link:

http://www.youtube.com/watch?v=U8nQ0VCNlig

Is this your bird? Nice looking and sounding airplane!

My wife & I were at a Oshkosh fly-in in the early 80s and she told me I "had" to see this airplane, so she took me back to see an RV-4. It made the cover of "Sport Aviation" after the fly-in and was named Candy Apple Red. Since then we have always liked the RV-4 design.

Will consider the Sonex if the RV-4 looks like it will not work out operating under LSA rules.
 
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That u tube link was for my good friends Cleanex,(red and white) mine is polished and blue) i built his engine mount etc. I have some video on utube, try " dan's fly by " (the only one i could think of) my site should be up soon? Several freinds on VAF have seen flown ,and dog fighted with me, its about as close to RV as you can get and still be LSA Dan (would still love a LSA RV
 
That u tube link was for my good friends Cleanex,(red and white) mine is polished and blue) i built his engine mount etc. I have some video on utube, try " dan's fly by " (the only one i could think of) my site should be up soon? Several freinds on VAF have seen flown ,and dog fighted with me, its about as close to RV as you can get and still be LSA Dan (would still love a LSA RV

Found your flyby:

http://www.youtube.com/watch?v=Ps3cbICtq_A

You probably got grass on your prop during that flyby. Guessing an immelmann to get turned around at the top.
Nice job! :D

You got me thinking about the Sonex for "sure" if it does not work out with the RV-4! They now have acro ailerons with increased span ailerons and decreased span flaps for a faster roll rate:

http://www.sonexaircraft.com/aircraft/sa.html
 
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cleanex website up

Hi Guys my website www.flycleanex is now working . On the home page in the upper middle you can click on "newly polished album" for some good pics last time i polished it up. I should add that i built from plans and i have $16,000 in to date! i have about 950hrs building including design and building the engine install/cowl. Thanks Dan
 
RV4 LSA

This may be a different topic,but I am investigating one of Subaru engines that range in HP from 120-160 without doing anything crazy.Possibly a direct
drive ? ? I am trying to finish RV 4 as light and simple as possible,similar to what DR is doing with 3B.I don't need a rocket ship,but even a slow RV 4 would be faster than most production airplanes I have flown.( Cessna-Piper )
I would not be surprised If by time I finish (old slow build -4) and need engine
the Chinese will have an electric one.
 
This may be a different topic,but I am investigating one of Subaru engines that range in HP from 120-160 without doing anything crazy.Possibly a direct
drive ? ? I am trying to finish RV 4 as light and simple as possible,similar to what DR is doing with 3B.I don't need a rocket ship,but even a slow RV 4 would be faster than most production airplanes I have flown.( Cessna-Piper )
I would not be surprised If by time I finish (old slow build -4) and need engine
the Chinese will have an electric one.
This does not compute. A Subaru engine in a light airplane is an oxy-moron.
 
CubCrafters had their engine manufacturer make up that continuous power limitation. As builder of your own engine, you could do the same, but if something happened and you ended up in court for some reason, I think you might have a difficult time with defense.

Mel,

I realize this is an old thread but could you expand on this some. My understanding is their engine is custom and as such, warrants the max power rating. Do you think a Carbon Cub owner would have a problem, or do you just mean an individual? If just an individual, then why so?

Luke,
 
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