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-   -   Jabiru 3300 RV-3 (https://vansairforce.net/community/showthread.php?t=92301)

Lucky Clover 10-21-2012 03:57 PM

Jabiru 3300 RV-3
 
Just ordered my rv3 kit. Will mostly be using it for cross country trips. The jabiru is 120hp but is much lighter than the other suggested engines. Will I have to worry about my cg?

gasman 10-21-2012 04:33 PM

Quote:

Originally Posted by Lucky Clover (Post 709692)
Just ordered my rv3 kit. Will mostly be using it for cross country trips. The jabiru is 120hp but is much lighter than the other suggested engines. Will I have to worry about my cg?

Yes. So why don't you just use an 150 Lyc?

Lucky Clover 10-21-2012 04:35 PM

Having to build on tight budget. Can get a new jabiru with fwf for $24000

Alschief 10-21-2012 04:46 PM

RV3 FWD
 
Suggest you give the UL Power a look
It is a fine power plant.

David Paule 10-21-2012 04:48 PM

You can get a used Lycoming for less....

I flew behind a Jabiru 3300 recently and was impressed by it. The only part I didn't like was its Aerovee carb. Can't see any reason to have one of those. But the engine was smooth and powerful, light and small. Started instantly.

It's roughly 80 to 100 pounds lighter than the Lycomings, and that's bound to introduce some CG issues. If you move the engine forward, you're moving the prop forward and that reduces stability. It's not exactly a slam dunk. But if you can bring it off, you'll find a number of people interested in it.

Dave

Lucky Clover 10-21-2012 05:08 PM

The jabiru is highly supported and easily installed. Have been looking over the rv3 layout. Considering the ways to move the cg forward without having to relocate the engine forward.

N941WR 10-21-2012 06:16 PM

Quote:

Originally Posted by Lucky Clover (Post 709692)
...Will I have to worry about my cg?

Yes but since you will need a custom engine mount anyway, have it made longer
Your bigger issue will be controlling the high CHT's the Jabirus are becoming known for.

rph142 10-21-2012 06:37 PM

Moving the cg forward wont be too tough. If I were you I would extend the .032 front side skins, floor, and top skin. You have to cut all of these pieces to size anyway, so it won't take any longer to cut them longer.

cubdriver 10-21-2012 07:50 PM

Engine Choice
 
If you want to build light, you might consider Lycoming's new o-233 116 HP engine. It is a great engine, should solve CG issues and can use a factory supported engine mou t from Vans. I have one in an RV9 and it works great. Plane is light and nimble.

highflight42x 10-22-2012 12:23 AM

RV3 CG w/Jabiru engine
 
There would be a *severe* cg problem in a standard RV3 with an engine 80-100lbs lighter than a Lycoming.

With such an engine, the engine mount will need to be re-designed and the fwd fuselage possibly extended. Either way, you'll have a very different structure fwd of the cockpit, implying some serious structural analysis and design work. The flight characteristics could change drastically - the farther fwd the engine, the more different the inertial characteristics will be.

This engine will require an entirely new cooling solution, new cowling, baffling, fuel and exhaust systems. These secondary tasks alone will be quite expensive. Is there a propeller for the Jabiru with the pitch/diameter needed for the RV3's speed envelope?

In short, to install an engine that the aircraft was not designed for, you will become a true experimenter. I'm not trying to persuade you not to do this, just be aware that with a new untried engine installation, it will cost much more than you originally intend, and will take 2x (or more) time to do it.

good luck!

- Steven
RV3 builder/pilot
(700+ RV3 hours)
(... 1.5 more today!)

Yen 10-22-2012 01:38 AM

Jab 3300
 
The 3300 Jab will come with all the cooling shrouds necessary, also fuel plumbing and exhaust. I found fitting a Jab engine to the Corby I built to be far far easier than fitting the 0-320 Lycoming to the RV4 i am building. The cooling shrouds are a right pain in the butt. The fuel plumbing fouls the engine mount, exhaust anf firewall. The actual engine mounts look as if they ere designed to be difficult, had to turn the bolts to torque them up.
If you do go with the jab, don't use mogas, unless you are very sure of its quality. I had a detonation problem when I couldn't get avgas.

madhun 10-22-2012 03:23 AM

I'd be inclined to have a good read up on the issues surrounding Jabi engines, which I wasn't too familiar with prior to attending a recent RA-AUS fly in at Monto (QLD); there wasn't too many complimentary discussions regarding what I thought was a widely accepted engine.

KatieB 10-22-2012 06:48 AM

Quote:

Originally Posted by madhun (Post 709814)
I'd be inclined to have a good read up on the issues surrounding Jabi engines, which I wasn't too familiar with prior to attending a recent RA-AUS fly in at Monto (QLD); there wasn't too many complimentary discussions regarding what I thought was a widely accepted engine.

The "issues" are due to improperly designed cowlings. Jabiru USA figured this out a decade ago. Cooling a Jabiru in a fast airplane such as the RV-3 would be easy. The CG would be the biggest challenge because it's such a light engine.

Good luck, I think it would look awesome with a long, sleek nose. Like a mini-Rocket.

JDRhodes 10-22-2012 10:22 AM

Quote:

Originally Posted by Lucky Clover (Post 709699)
Having to build on tight budget. Can get a new jabiru with fwf for $24000

:eek: We spent $10K on a mid time FWF Lycoming WITH and prop and baffle and exhaust. And it fit right on the RV mount and inside the RV cowling with no engineering. Is it brand new? No, but I haven't given it a second thought since it went on, the CG was right from Day 1, and with 1,100 hours to TBO, it'll probably give 10-15 years of flying.

I wouldn't consider a $24,000 engine if I was "building on a tight budget." Especially not an "alternative" engine.

David Paule 10-22-2012 10:42 AM

The Sonex props might be reasonable starting places.

The cooling can be dealt with. A friend flies the 3300 and has had oil cooling issues but not cylinder head issues.

The main issues will be the CG and the new cowling.

Dave

RV3b Pilot 10-22-2012 12:58 PM

Engine weight
 
I have a RV3b with a Corvair engine in it and it is much lighter than a Lycoming so I did several things to make it work out:
1st I used a RV4 cowl which is longer and I fitted it to the RV3 fuselage as far forward as I could get it and have it fit good. Then I fitted the engine to the cowl, that is backwards as most will mount the engine and then the cowl.
Then I made sure that every heavy object was as far forward as I could get it, even my battery is against the firewall.
I wanted to turbo charge my engine so that added some weight.
I made my own propeller hub out of 3/8" thick solid steel.
I made my own motor mount and added extra heavy pipes and weld plates.
My Corvair engine is only 178 cubic inches and I cruise at 190 MPH at 7,500 MSL and being turbo charged it goes even faster up higher! It is very smooth because it is a 6 cylinder engine like the one you want to put in your aircraft.
My weight and balance was right on but my aircraft is heavy becasue I wanted all the heavy gauges and radio, GPS, etc... 852 pounds empty...
You can do it if you want to and it will work out if you take your time and plan carefully. It took me 10 years and just over 3,000 hours of build time, about a 1,000 or so of those hours where just getting the engine to fit! It will add about one year to your building time to go with something other than a Lycoming.
With a Lycoming you can just purchase the parts and bolt them on. With any other engine you make all the parts, exhaust, intake, motor, mounts, accessories, etc....
Right now I am flying off my 40 hours and have had several mechanical issues that are specific to my engine installation. Today I lost an alternator belt in flight and because everything is such fit in the back of the engine it takes me about 5 to 6 hours to put on a new belt.
But there is nothing like having a true experimental aircraft and have it fly.

dicel87 10-22-2012 01:47 PM

Can you post some pictures of your corvair powered RV? Sure sounds interesting and truly experimental. Congrats on seeing your hard work pay off.

Lucky Clover 10-22-2012 07:02 PM

Thank for all the great advice. It gives me a lot to think about. As for the tight budget I only have about $35,000 set aside for engine and avionics and the misc. costs of the project.

YellerDaisy 10-22-2012 07:14 PM

Quote:

Originally Posted by Lucky Clover (Post 710115)
Thank for all the great advice. It gives me a lot to think about. As for the tight budget I only have about $35,000 set aside for engine and avionics and the misc. costs of the project.

:eek: Wowsers!! Apparently "tight" is another one of those subjective words. I don't have that much in my ENTIRE RV-3B (with +200 hours in her).

I've done the experimental engine thing (successfully) and I've done the aircraft engine thing. My only advice is to consider very, very carefully how you really want to spend your time because there is no comparison. Take your most pessimistic estimate, double it, and add 50%. Head scratching time adds up really quick!

David Paule 10-22-2012 07:40 PM

Quote:

Originally Posted by RV3b Pilot (Post 709965)
I have a RV3b with a Corvair engine in it....
Right now I am flying off my 40 hours....

Congratulations! That's very impressive. How about some photos and more description?

Thanks,
Dave
RV-3B, on rudder now

Yesterdays-3's 10-31-2012 10:58 AM

Original plans allowed for use of O-200
 
Van's original RV-3 plans allowed for a Lycoming engine or a Continentel O-200 configuration. The plans modified the cockpit seat pan and engine mounts (not only mount, but dimension changes) if I remember correctly.

There have been several O-200 powered -3's built, but I have not actually seen any of them first hand. I have a picture and an RVator wright up of one if you are interested.

If you are interested in seeing the modified plans for the lighter O-200 engine let me know. It would most likely have to have further mods for the Jabiru but would give you some known starting points.

Rob Reece

jim miller 10-31-2012 04:25 PM

You can find a 0235 C series engine core for 1500-3000. With a premo
overhaul including new Lycoming cylinders and Cam you will have less
than 15K maybe 12-13K and have for all practical purposes a "New"
engine good for 2400 hours TBO. I have such a engine in my RV3 that
was overhauled like I just described to use in my Colt about 400 hours
ago. The only cooling problem I have with my installation is the oil
temp is hard to get up enough to boil off the moisture from the engine.
I have yet to see more than 180 degrees with the oil cooler blocked off.

Jim Miller

RV3bpilot 11-01-2012 09:34 AM

Pictures of my RV3b with the corvair engine is on the RV3 registry and also on Van's web site, click on the first flights.

10 G 01-03-2014 06:14 AM

Quote:

Originally Posted by Lucky Clover (Post 709692)
Just ordered my rv3 kit. Will mostly be using it for cross country trips. The jabiru is 120hp but is much lighter than the other suggested engines. Will I have to worry about my cg?

so did you decided to go with jab 3300?


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