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Jab 2200 ?

KeithO

Well Known Member
Given the cost of the Rotax at nearly 25k, has anyone contemplated the sacrilegious thought of slipping in a Jab 2200 for half the price and a lot less complexity ?

There are no preview plans for this airframe, so I have no point of reference to make a determination of just how much work would be involved. I also do not know of anyone close to where I live who owns one that could be inspected.
 
I'm a big fan of the Jabiru engine. Unfortunately the way the RV-12 has been completely designed around the Rotax, it would be very difficult to modify it for the Jabiru. If you used the 2200, you would be sacrificing 15 hp and the 3300 is heavier than the Rotax.
I would really like to see some research on this type of project, but you need to be aware, it would NOT be an easy task.
 
Hello Mel. I have heard that the 12 is a highly integrated design. Does this mean it has no conventional engine mount ? The Hummelbird, for instance, had rails that were part of the fuselage which formed a bed mount for the VW engine. The 2200 has 15-20hp less than the rotax and thrust would be lower due to the smaller prop and higher RPM. It should save about 30lb on overall weight though. The 12 has a very satisfactory climb rate with the 912S and some may be satisfied with slightly less stellar performance for a substantial reduction in cost.

Another alternative is the BMW R1200 with a reduction drive which would swing a decent size prop and of course in the meanwhile there is the Egenfeller HF 110 which Honda Based and they are claiming >100hp at <$13k. The R1200 engine can be found for less than $1000 and the redrive from Air Trikes in canada is about $2500, so there is still a lot of margin before one hits the price of the Jab 2200 or the alternatives. Many of these engines are flying in Europe.

I think it is hard to beat the price and convenience of the airframe from Vans, but more affordable powerplants are needed...
 
not an apples to apples comp...but I could only find $4000 diff between the 912 and the Jab. But I don't know what is included with either engine
 
The 912S has quite a bit of hardware in the FWF kit. There is a radiator, hoses, oil cooler, hoses, external oil reservoir, coolant header tank and a bunch of other stuff.

Its possible that Vans includes the prop and spinner in the powerplant kit for just over $26k but that is more money than a zero time Lycoming O235 or even an injected IO360. Either the Lycoming or the Jab would do fine with a simple wooden prop, but of course the 0235 would be far too heavy. The problem is simply that Rotax is king of the hill in the small engine division and are charging what they think the market will bear. It seems absurd that it costs more than double for the engine compared to the innumerable parts for the airframe.
 
FWF kit- no way to compare

Keith:

The RV-12 FWF kit does include the prop and spinner plus many other items that are not part of the 912 itself. Just a few examples are all FWF wiring harnesses, cooling shroud for the cowling, battery, exhaust system, and the list goes on. I don't think anyone has yet made an attempt to separately price all of these individual items but I do know that a few overseas builders that sourced the 912 elsewhere and then tried to obtain everything else separately have found it to be a losing proposition. Not to say it could not be done but the underlying point is that I have yet to see a true apples to apples full cost analysis of another option.

Jeff
 
I'm with Mel on this one. Not easy. The engine footprints are quite a bit different and the large step in the RV12 firewall creates problems for the low mounted carb on the Jab. Looks like you might need a prop extension to make the Jab fit under the cowling plus mod the cowling a lot for the air inlets and maybe even reshape the whole top to clear the starter. The offset gearbox on the 912 allows the engine itself to be mounted lower than the direct drive Jab.

Certainly no standard Jab mounts I've seen could be easily adapted to the RV12.

Probably a lot harder than putting a Subaru in a 6, 7 or 8.

Lots of work I think and it might not fit at all without moving the carb or seriously modifying the front structure of the aircraft.

There are some drawings here: http://www.jabirupacific.com/specs/2200.htm

http://www.rotaxservice.com/documents/912Sdraw.pdf
 
Reality...

Based on the number of views, these engine option threads are popular. But I question the economical outcome of adapting a less expensive engine to the RV-12. Assuming that a few thousand could be saved (doubtful), by using a different engine, fabricating new mounts, obtaining a different propeller, accessory package, Dynon sensors, etc.

Then you have to consider the resale value of an E-AB plane with lots of modifications vs. a fully compliant Van's E-LSA.

And there is the aggravation factor in having to engineer the changes and shop out the parts fabrications. It is doubtful that Van's will offer engine options on the -12.

Then there is the reduced performance with a lower HP engine. You would have to throw the RV-12 POH out the window and write your own.

Gosh, it is really worth it? I think not.

The few thousand that could possibly be saved in construction would be offset by hours of frustration and ultimately by 10s of thousands of lost resale value...in my opinion.

Tony
 
Tony, I respect your point of view as someone looking for a "turnkey" package. If one has the financial means to write the check for a $26k powerplant for a $12k airframe, that is all very well. Unfortunately, about 80% of the US population and probably 99% of the rest of the worlds population simply doesn't have that amount of disposable income, nor would they be able to afford the long term care and feeding of such a unit.

Used Rotax engines are pretty scarce. Used or unused Jabs are to be found. There are some 2200's listed for $8500 which was the price paid when bought and the kits they were purchased for were never built.

The rest of the challenges are well within the scope of an "experimental" airplane project and it is nothing unusual to fabricate one's own engine mount and cowling. I know few people who look at an airplane like this as an "investment", if I did, I would be buying stock on wall street or foreclosed homes instead...

What is unfortunate is that this is one of the few sport pilot class airframes out there that is produced with this level of sophistication, but offering just the 1 expensive engine option. I can't blame Vans, since they are pretty much forced to work with off the shelf engines. Given that the basic RV12 development is meanwhile complete, I hope Vans re-visits the engine question, since times have changed since the start of this project.
 
Jab 2200

Then there is the Eggenfellner Honda Fit HF-110 engine which is just coming online. Though the engine weighs slightly more, it produces more horses and the weight can be compensated by moving things like the battery aft. There may be other weight savings with elimination of the oil tank, cooling duct, rectifier, etc.

Jan promises a new cowl, a three blade Sensenich propeller gear reduction and engine mount. I have concern about the location of the engine mount on the firewall. Will it be a direct fit or new design as this could add more weight.

But at about one half the cost of a Rotax, It's aweful appealing. Just think, no carburators to balance; no oil warm up; no engine burping; no high cost parts.

The down side is a little added weight; relocation of the pitot tube to the wing; a new heating system; a different avionics package; certification to Amature Homebuilt.

The up side is low engine cost; more power; sexy prop; ability to add an angle of attack pitot; your choice of avionics; less costly avionics packages; no locks on the avionics software.

Looks good to me, but I need more info before putting down the money.

Art Pennanen
 
Another Engine Option to consider

To really build an inexpensive flyer it does seem that using all the kits except the firwall forward and avionix plus a Greatplanes VW based engine with a redrive would be feasable.
Of course you would have to develop a custom cowling, mount etc but thats not a show stopper. Its what most people had to do before the age of cad produced kits.
I wouldnt consider it on any other airplane really but with such a docile airframe and removeable wings the ineveitable forced landings would be non events :)
You get what you pay for is sure true here.
Rick
 
Hey Keith,
I think I misunderstood your original post. I totally agree that the RV-12, as designed, is a turnkey package, although there is 1000 hours of work before you turn the key;). But yes, that was the reason I chose the -12.

Your reference to the $12K airframe does not include avionics, finish kit, nor any of the fancy options like autopilot, interior, lights, or wheelpants. Without any of this, and with a different engine, maybe you could build something for $25-30K, about half the price of well equipped RV-12 ELSA. It would be a challenge and time consuming.

But, many, if not most of us 12 builders are "senior", do not need a lot more challenges in life, and do not wish to spend 5 or more years on the build. And we want a nice ride when it is done. I don't know if that kind of thinking was behind the design of the 12, but it sure fits.

Actually, if I were a younger guy, I would be looking at building something more exciting than the 12. And, if I were younger, resale would still be an important consideration, so that I could upgrade to an even better future project.

Tony
 
Hey Keith,
I think I misunderstood your original post. I totally agree that the RV-12, as designed, is a turnkey package, although there is 1000 hours of work before you turn the key;). But yes, that was the reason I chose the -12.

Your reference to the $12K airframe does not include avionics, finish kit, nor any of the fancy options like autopilot, interior, lights, or wheelpants. Without any of this, and with a different engine, maybe you could build something for $25-30K, about half the price of well equipped RV-12 ELSA. It would be a challenge and time consuming.

But, many, if not most of us 12 builders are "senior", do not need a lot more challenges in life, and do not wish to spend 5 or more years on the build. And we want a nice ride when it is done. I don't know if that kind of thinking was behind the design of the 12, but it sure fits.

Actually, if I were a younger guy, I would be looking at building something more exciting than the 12. And, if I were younger, resale would still be an important consideration, so that I could upgrade to an even better future project.

Tony
I'm buildng the -12 fo all the reasons Tony T mentioned. Thanks Tony. Amen

Gary -
 
ditto on the turnkey package

Me as well- the turnkey package was the most attractive feature to me and I am not senior!

Frankly, I would submit that if the goal is to build something for less, then the RV-12 is probably not the right plane. Can you do it- I am sure it is possible. But there are other sport planes out there that were not designed as turnkey packages and have FF configurations that make them much more suitable to a variety of engines. Having said that, not many are produced by manufacturers that have the same level of experience and reputation as Vans. However, there are still some good ones.

Regarding engines- I have to agree with hydroguy2. I just did my first engine run last weekend and I found the carb sync no more difficult than setting the timing on a set of mags. The burping takes a few seconds. It does not take all that long to warm up. Yes- the 912 does take some adjustment for those like me that have always flown behind a Lycoming or Continental (I forgot to turn off the choke for several minutes!!!). However, it is a proven design, has a long TBO now, and I am hoping that as it becomes increasingly popular in the US, parts will become available from other vendors and perhaps will lead to some drops in parts prices. Being accustomed to the prices of replacement parts for my old Skyhawk, I guess I have not been quite so shocked by parts prices anyway!

Jeff
 
Given the cost of the Rotax at nearly 25k, has anyone contemplated the sacrilegious thought of slipping in a Jab 2200 for half the price and a lot less complexity ?

Since the Jabiru factory has in the past offered firwall forward kits for various airframes I would suggest that they may have already given this question some consideration.

Give them a call and ask - I'd be interested in the response you receive.

Personally I am not considering another project for now but if I was building the 12 I would at least ask the same question. Note: I have no preference for Rotax or Jab, nor do I work for either company.

Doug Gray
 
Some here have reacted to the cost of the Van's Rotax engine package, yes it is an expensive package but it is good value for the money.

If I were trying to build a RV-12 for the lowest cost that I could it would be an EAB with the 80 HP Rotax 912 purchased used and the rest of the needed parts from Van's. This would still make a fine flying aircraft for anyone living below 2000 feet above sea level and you could save over $ 10,000.

You could also find older instruments and radios do a good bit more work to work out a safe installation and perhaps save another $ 5,000.

If you fly it with out paint or paint it like Van did his, by your self or with spray cans you could save another $ 5,000.

You would still have a fine aircraft, not quite as nice as one built to the ELSA requirements but a very nice aircraft and you would only have about $ 45,000 in it.

My first RV-12 had almost $ 70,000 in it and it had every option except the second Dynon and wheel pants. So it is up to each person to build what is in their price range and an aircraft that will meet their needs.

The Jab engine is a fine engine but as others have pointed out the engineering required to make it work on the RV-12 would be costly and take a lot of time to sort out. It could be a fine combination.

I think $ 70,000 for a very well done out LSA aircraft is a real bargain given the price of off the shelf LSA aircraft, which run between $ 120,000 and $ 140,000 for an aircraft of similar quality with about the same equipment. A RV-12 for around $ 45,000 would be fine if money was that tight. Personally I would just stay with my Luscombe 8A if the RV-12 was more than I could handle.

Have a good day.

Best regards,
Vern
 
Jabiru

Doug I spoke to the Jab factory yesterday while thay are not interested in doing any development work for fitting their engine (either 2200 or 3300) to the RV-12 they of coarse could supply. The only comment he said is that the 3300 6 Cyld. engine is 20 kgs heavier then the Roatx setup so boys if you can work around that way ya go!


UOTE=Doug;453531]Since the Jabiru factory has in the past offered firwall forward kits for various airframes I would suggest that they may have already given this question some consideration.

Give them a call and ask - I'd be interested in the response you receive.

Personally I am not considering another project for now but if I was building the 12 I would at least ask the same question. Note: I have no preference for Rotax or Jab, nor do I work for either company.

Doug Gray[/QUOTE]
 
Tony, exciting may be good, but I'm sure we all remember the days that Auto gas cost $5/gal and 100LL is at $4.88/gal right now. I don't think we will have to wait too long before India and China start ratcheting up consumption and the price begins climbing again. While there are still people with money, statistics are showing that the ratio of the have-nots continues to increase. So part of my long term planning does not include a fast thirsty sport plane that I will no longer be able to afford to fly in a few years. If a Utopian world with a "higher standard of living for all" were to magically arrive, I guess I may indeed consider something faster and more expensive to run when everything else is paid for...

Fuel cost is one of the largest expenses on a per hour basis (providing one actually flies the airplane of course). I had to laugh at the references to carburetors, since I have no intention of flying behind a carburetor, ever. In fact the only vehicle I have ever owned with a carb was a 70's model Datsun. So I will not be using magnetos nor carburetors on anything that I fly, period. I develop injection systems in my current job, which includes the design of the injector itself as well as the drive circuits and associated test equipment, both for atomization and durability. So, at least I have the advantage of not being a novice in this field... My plan is to use primarily Mogas, which by itself is a saving of nearly 40%. Waiter IFLYEZ.com has a pretty extensive summary of several years of operating costs and even then, fuel came to $12/hour against engine overhaul costs of $6/hour. Even Hanger rent came to $6/hour, one of the other large expenses. In the meantime, fuel is 2.x the price, the hanger rent is only slightly higher and of course overhaul cost on Lycomings and other engines has risen by about the same scale as the fuel price. I think it says something about the devaluation of the currency, more than anything else.

The attraction to the 12 is the fact that it is the only airframe from Vans that has been designed for <100hp. The 9 really has 115hp as the minimum and going up from there. I have looked at the offerings from Zenith and others and they simply don't hold a candle to an RV, even though a lot of people have been critical of the exposed rivets and other features on the 12. A Sonex would be a really tight fit for me at 6'6" and it is pretty narrow too. I won't even comment on the styling and there is virtually no difference in price. I'm looking to build an UltraVair engine (2 cylinder Corvair conversion) for a legal part 103 Ultralight, but I don't think I want to fly behind a VW conversion in a 2 seat airplane. When experts like Bob Hoover claims that one cannot make more than 60hp reliably from a VW, I am inclined to pay attention.

I intend to have a pretty spartan cockpit and will not buy any avionics until every other detail has been taken care of, since this is still a rapidly evolving market and what used to cost $40k 5 years ago is now available from reputable sources for $12k. Even better, entry level moving map GPS with weather overlay is offering more bang for the buck year after year. EAB means I get to change what I want, when I want and do all my own maintenance.

I have followed the saga of the BK1 now for several years and had this project been wrapped up 2 years ago, I might have had 1 built by now. It is a perfect example of getting ahead by sweat equity, since Bruce King only had a little over $5k in the prototype (single seater of course). Now that I have waited this long, I need to do a 2 seater so that my wife can get some enjoyment out of it too...
 
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Vern, just as a point of reference, you can go and write a check right now for a brand new Flight Design CTSW for $89k New Flight Design CTSW and that will not take bucking a single rivet, in fact you get a nice sleek composite fuselage.... I have a hard time believing that an RV12 is going to hold its value better in a restricted category compared to a factory built composite airframe.
 
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Vern, just as a point of reference, you can go and write a check right now for a brand new Flight Design CTSW for $89k New Flight Design CTSW and that will not take bucking a single rivet, in fact you get a nice sleek composite fuselage.... I have a hard time believing that an RV12 is going to hold its value better in a restricted category compared to a factory built composite airframe.

Hi Keith,

The aircraft you pointed out is a 2007 aircraft that is still for sale and it does not include the avionics package which they list at a minimum of $ 6,500. You are right it is less than the $ 120,000 I indicated but it is not a true new aircraft and it is over $ 96,000.

Then there is the CTSW flight issue to be dealt with, a good number of them have crashed due to stalling the elevator near the ground, we had one here at Spruce Creek that was crashed at Oshkosh three years ago, spent almost a year being repaired (new fuselage from Europe) and was crashed again about three months later and totaled that time. The pilot was a very experienced pilot with a good record until this. I also know of a flight school in Michigan that one of my friends taught at and it had to close as they had purchased four CTSW's and they were all crashed by clients in the same way on low speed attempts to go around. I do not know all of the details and am not an expert on flight characteristics but I do know that the RV-12 has very nice flight characteristics and some other factory built LSA aircraft do not have the same quality of safe flight handling.

The RV-12 is very good value for the money and a safe, fun to fly aircraft.

Best regards,
Vern
 
Vern, I was really not aware of the issues with the CT. I am really surprised, since they have been very popular in the European Ultralight category and I believe that requires a 35kt stall speed and was the reason why the wing was initially longer and the gross weight was lower. It sounds like when they did the clip wing and increased gross airframe changes they didn't get it quite right which is a very sad state of affairs. The discounted prices must be reflective of sales not going the way they wanted...

Looking at the Vans Aircraft cost estimator the lowball number for the RV9A is $42k. In the case of the RV12, which obviously isn't in the cost estimator, there is $39k listed just for the avionics and powerplant.

I guess there has been a fair exchange and the nature of the majority of replies illustrates what has become of a substantial part of the experimental aircraft community. I would not be surprised if the experimental (or at least kit built) category were to morph into something more closely resembling the new ELSA category with all of its restrictions, since no-one seems to be designing and fabricating anything of their own design anymore. Few seem alarmed by the cost of getting in at the low end of the spectrum with a very basic airplane devoid of bells and whistles. If I forgo the Jab 2200 and look at the Suzuki G13/G16 with a geared redrive, I would like to believe that one could build the RV12 for $24k, especially when Bruce King feels that the BK1 can be built for 10k complete.

Thanks for the comments and good luck all. If there is anyone near Jackson, MI who is building one of these birds, I would appreciate the opportunity to measure up the firewall to create a mockup for the sake of FWF engine/mount development. Please send me a PM if interested.
Keith
 
I've had my 2007 CTSW for 3 years and 210 hours. There is nothing wrong with that plane. As with any plane, a proper check out is important. This is especially true for pilots coming from cessnas and Pipers who are not used to light controls and light weights. If the CT is such a disaster, why is it the #1 S-LSA seller in the USA?
 
If the CT is such a disaster, why is it the #1 S-LSA seller in the USA?

Hi John,

Yes the CTSW "WAS" the best selling SLSA in the USA because it has many fine features and the best is the ease of access for people who may have trouble getting in and out of other aircraft. Like many aircraft it has some flight control issues (note I did not call it a disaster) like my Luscombe it requires good training or check out and then real respect for how it is flown or it has the potential to bite. The Luscombe is very demanding or it will ground loop the MU-2 has such interesting flight controls that the FAA had to get involved and they required special training, in the case of the CTSW if it is well handled it is a fine aircraft but if you are slow near the ground and add a lot of power as in a go around and then get abrupt on the controls you are likely to end up a Lawn-dart. They have come out with two or three new models with the same great general features and they say they have fixed this control issue and there do not seem to be so many crashes with the new models. I think this is why the 2007 "New" CTSW was being offered at $ 89,000 instead of its normal list price for a near new aircraft.

Fly your CTSW with respect for its issue and it will serve you very well.

Best regards,
Vern
 
Light control forces?

I've got a little time in a CT and I'd have to say it has poor control harmony. The ailerons are like a DC3 and it has quirky pitch response, especially at low speeds. The wing seems to give up flying rather suddenly. Challenging to land and not a nice flying airplane like an RV at all.

I was impressed with a lot of the design features and construction but the CT is not on my list of airplanes to own.

Once you've flown RVs, most other light aircraft's handling qualities don't seem very nice by comparison.
 
Kind of hard to see how a person could end up with a flyable RV-12 for only $24k, given that the airframe kits cost almost $23k.

If you want a cheap plane, there are any number of successful homebuilts from plans and kits that you can build. Most of them are single-seaters but a fair number are two-seaters. They won't have the performance or the handling characteristics of the RV-12, and probably not its durability, either, but they'll be cheap and they'll fly.

Or you can browse on one of the airplanes-for-sale sites like Barnstormers, and often find perfectly decent airplanes for under $10k. I've seen Kolbs, Druines, Pietenpols, Fishers, all finished and flying, for that sort of price, and for less than you can build one for yourself. If your budget is $20k, there's lots more airplanes, many with decent capability.

They aren't RVs, though. But they fly.

On the other hand you can modify the heck out of an RV-12. You'll add a lot of time to the build and you'll reduce its value and you won't be able to call it an RV-12. Also you won't save a lot of money - what you don't buy from Van's you'll need to buy somewhere else. Since things of about the same function, for airplanes, often seem to have a floor price: steam gauges plus avionics cost about as much as Van's avionics package, for example.

Seems to me that if you're serious about building an inexpensive airplane you might do better than choosing a highly integrated, thoroughly engineered one as a starting point. Find one that you build from plans, or design your own. The changes won't be as costly.
.
 
Here is the NTSB report of the CTSW accident at Oshkosh 3 years ago. Draw your own conclusions.
****************************************************************
NTSB Identification: CHI07CA228.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Accident occurred Tuesday, July 24, 2007 in Oshkosh, WI
Probable Cause Approval Date: 10/31/2007
Aircraft: Flight Design CTSW, registration: N377CT
Injuries: 2 Uninjured.
The airplane was damaged during landing. The airplane was landing at the annual Experimental Aviation Administration Airventure fly-in. The pilot reported that he was cleared to land on runway 18R and when he was about 3 feet above the ground the controller advised that he needed to extend to the blue dot. The pilot stated that he reacted and the airplane ballooned up 25 to 30 feet and the airplane stalled. He stated that a "tiny bit" of throttle would have been all that was required to extend to the blue dot and "all would have been well." The pilot reported no mechanical failure or malfunction of the airplane. The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot's failure to maintain adequate airspeed during landing which resulted in an inadvertent stall and subsequent impact with the ground.

*********************************************************

I do agree it does not have the control harmony of an RV. Very few airplanes do. They have springs to resist aileron movement and that sucks.
 
Jab Engines

Since the Jabiru factory has in the past offered firwall forward kits for various airframes I would suggest that they may have already given this question some consideration.

Give them a call and ask - I'd be interested in the response you receive.

Personally I am not considering another project for now but if I was building the 12 I would at least ask the same question. Note: I have no preference for Rotax or Jab, nor do I work for either company.

Doug Gray

Hi Guys have spoken to the Jabiru factory and they will NOT be offering any F/F kits for either the 2.2 or 3.3 engine installation for the RV-12. However of coarse they will supply engines to anyone willing to engineer up a package installation taking account of the 20 kg increase of weight of the 3.3 engine... love to see this done somtime as it sure is a Sweet engine!
 
W&B

I think all the comments about about the difficulties and reasonableness of adapting a Jab to the RV-12 are true. As someone who carefully watched the development of the -12, I think that you better do some preliminary W&B calcs on your conversion. The -12 was designed with seating forward of the main spar - and is dependant on the lightweight Rotax up front. Having flown and closely examined the 12... I don't think there is much space to pull an Jab rearward to try to overcome much increased weight in the nose. I guess you could put some bricks in the tail. ;)

That said... my hat's off to all the true "experimenter's" in Experimental aviation. If you think you can make it work... go for it. :eek: That's how advances are made. I like the simplicity of the Jab. While my ability to build is on hold for a bit, I am peeking at the Jabiru powered LSA Arion Lightning.

Personally... my current fantasy is for Van's to design a new LSA version of the RV-4 with a Jabiru 3300 or the new Lyco O-233. I'd love to see it open cockpit... like the old PT-19... :D
 
Jabaru 3300

If someone is seriously interested in putting a 3300 in a 12 they should contact Pete at JabaruUSA in Tennessee. He has a very good and complete firewall foward kit for the Zenith series aircraft. It includes everything, Cowling, Spinner, Prop, hoses, ect. Everything is bolt on, almost no fabrication is needed. They might be interested in working with someone in developing a kit for the 12.
 
Jabiru Engine install

Gentlemen and ladies,,

Jabiru USA Sport Aircraft LLC. of Shelbyville, Tennessee is interested in creating an installation for the rv-12 with the 2200 and the 3300 engine. if there is anyone out there in RV land that is near the middle Tennessee area that is near completion of the fuselage, and is willing. We would like to borrow it to make up the engine mount and cowl plugs to begin the R & D of the installation. If anyone is interested please give us a call. 931-680-2800.

Thanks

Ben
 
Somebody ought to explain to them that they'd also need to set up the Dynon with the characteristics for their engines, since the avionics package, which includes it, comes with it set up for the Rotax.

Will their installation let the builder qualify those airplanes for the E-LSA category? Or will they be E-AB?

Will they issue a new POH to cover the different performance and operating characteristics? How about a revision to the Maintenance Manual, too?

It's not merely the engine installation, it's the whole system.

Just askin'....
 
David

The easy answer to the avionics setup up is that the Jabiru engine is already being used with the Dynon system so there is not an issue there. The airplane would have to be EAB because there won't be an SLSA constructed with the Jabiru engine to make the it legal to do the ELSA. Also being an EAB you would not be restricted to using the Dynon. It would open up the ability to use GRT, AFS, or any of the electronic stuff that YOU want. Or nothing at all, just a few round gauges. The airframe will not change, so if there is a maintenance manual from Vans for the plane that is all that is needed. Obviously the engine will be different and that is easily solved when you open your new engine crate and remove the CD that contains the maintenance, installation, and parts book for the engine. Making a POH for your experimental is not that hard to do.. and determining the performance and operating characteristics is the entire reason that the FAA requires a 40 hour flight test period for experimental airplanes.

Ben
 
Phase I Test Period

Making a POH for your experimental is not that hard to do.. and determining the performance and operating characteristics is the entire reason that the FAA requires a 40 hour flight test period for experimental airplanes.

Note that if built as an E-LSA, the required flight test period is only 5 hours. Thus, with the introduction of E-LSA, not all experimentals require a 40 hour flight test period. I am guessing this is part of the reason David asked the questions that he did. Not saying that some would not mind a 40 hour flight test period in exchange for the flexibility of building E-AB. However, others might prefer the more limited Phase I that comes with the E-LSA route.

Jeff
 
The Jabiru guys have already done a FWF for the Rans S-19. You can see it at their site here http://www.usjabiru.com/ranss-19.html .

It is only a matter of time before they do one for the RV-12. As you can see Ben is soliciting a volunteer now. It would be interesting to see what a 3300 does to the performance specs on the -12. Whoever goes this route can save money on both powerplant, and also have the option of simplifying the panel, less expensive radio/transponder, etc... potentially cutting a good chunk of change off the overall build cost. But they'd have to be prepared for a lot more work... working outside of the RV-12 instructions - and papering it as an E-AB

But then... having seen the superb build manual those folks did for the Lightning... I would have to think they'd have that well covered for their FWF kits.

DJ
 
Will be interesting to see how all that fits in there given the very different firewall shape the -12 has to the other aircraft where Jabs have been used.

Power to you all for the will to do it but the 2200 is 20hp short and the 3300 is a lot heavier than the 912S...

If you follow the Jabiru engine forums, there are still issues with these engines especially in the head, head bolts and valvetrain. The older engines had even more issues and the heads have been considerably redesigned 3 or 4 times now. The 912 has few problems by comparison if operated by the book.

People might want to research this one more before they jump on the bandwagon. http://groups.yahoo.com/group/jabiruengines/
 
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Putting the Experiment back in EAA

I been talking to Ben about the 2200 for a few months and I think he has a good handle on this. The engine assembly is about 35 lbs lighter and will cause the engine to move forward about 4 inches to keep the cg correct. This should help the stubby look of the RV12.The 2200 is less then 10 hp short at cruse rpm. The fuel consumption and rpm will be less then the rotax. The forty hour fly off should be no problem after 1000 +- hours of construction time. It will also allow you to use any radio system you would like, or none.
This looks like a good substation for those who want to save up to $20,000. The Rate of Clime and Cruse will be a little less. In my deduction the rate of clime 775 to 800 fmp and the cruse 125 to 127 mph if kept on the light side, empty weight 720.
I will build my 12 to the plans and document the construction and leave this option open.

Joe dallas
www.joesrv12.com
 
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I was looking at a Jabiru LSA at one point and when searching for planes I was noticing this a lot, "300 TT airframe and 100 SMOH engine". ADDED - This was 3 or 4 years ago and the 2.2 engine. I am sure things have improved.

Just my input.
 
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The easy answer to the avionics setup up is that the Jabiru engine is already being used with the Dynon system so there is not an issue there. The airplane would have to be EAB because there won't be an SLSA constructed with the Jabiru engine to make the it legal to do the ELSA. Also being an EAB you would not be restricted to using the Dynon. It would open up the ability to use GRT, AFS, or any of the electronic stuff that YOU want.
Ben

The Rotax engine parameters are already programmed into the Dynon when the Van's avionics package is used. It's a good implementation. Either the Jabiru developers or the builder would need to go in and change all that.

If it's the Jabiru developers, well, there's a bunch of other parameters which are unique to the RV-12 which have been integrated into that Dynon, and they all need to be included.
 
There are many airplanes out there that have AFTT different than the ENGTT. Many of them had the engines replaced for many different reasons. Of the jabiru engines that come through our shop for service or repair most are from Prop Strikes or an incorrect installation. There are not many engines out there that when properly installed have issues. Jabirus are no different. I spend much of my time on the phone helping builders correct their engine installation so the engine will work right and last. This is the reason that we do the firewall forward kits that we do. 601s,701s, 750s, S-7Ss, S-19s, to name a few. It gets the hard parts of an engine install done for the guy building the plane.

Ben
 
I been talking to Ben about the 2200 for a few months and I think he has a good handle on this. The engine assembly is about 35 lbs lighter and will cause the engine to move forward about 4 inches to keep the cg correct. This should help the stubby look of the RV12.The 2200 is less then 10 hp short at cruse rpm. The fuel consumption and rpm will be less then the rotax. The forty hour fly off should be no problem after 1000 +- hours of construction time. It will also allow you to use any radio system you would like, or none.
This looks like a good substation for those who want to save up to $20,000. The Rate of Clime and Cruse will be a little less. In my deduction the rate of clime 775 to 800 fmp and the cruse 125 to 127 mph if kept on the light side, empty weight 720.
I will build my 12 to the plans and document the construction and leave this option open.

Joe dallas
www.joesrv12.com

Since you would be doing EAB rather than ELSA, you could possibly do some things to reduce drag that would result in a few mph gain, giving you the same cruise speed. Things such as flush blind rivets rather than full head rivets on the exterior should give you a few knots. Additionally, you could reduce the size of the nose wheel to be more like the one on the 6/7. With the new engine, you could potentially reshape the front cowl to be more aerodynamic.

Finally, if you were willing to give up a bit on the stall speed, you could shorten the wings a rib. That would decrease drag a bunch and SHOULD only affect your stall speed.
 
As some points for comparison:

912S- 100hp for 5 minutes, 95 hp max continuous. Weight of our UL EFI test engine with plenum, pump, reg, injectors, ECU, exhaust/ muffler, rads, oil cooler, tank etc. 138 lbs. No oil or coolant. If we assume 1 gallon of coolant, say 148 lbs. for a weight to power ratio of 1.48 lbs./hp.

2200- 85hp at 3300 rpm. 132 lbs. stated on website. Not sure what that includes. 1.55 lbs./hp. The engine won't provide 85 hp at under 3300 rpm where most people seem to operate them.

3300- 107hp at 2750 rpm/ 120hp at 3300 rpm. Weight 180 lbs. 1.5 lbs./hp. at 3300 rpm and 1.68 lbs./hp at 2750 rpm.

It should be noted that the center of mass position on the Rotax is further aft in comparison to the Jabiru due to the gearbox and oil tank. I'd be surprised if the 2200 would be moved 4 inches further forward with regards to the prop flange to maintain the same aircraft C of G.

Cool project. Very interested to see one mounted up, W&B and performance comparison!:)
 
Since you would be doing EAB rather than ELSA, you could possibly do some things to reduce drag that would result in a few mph gain, giving you the same cruise speed. Things such as flush blind rivets rather than full head rivets on the exterior should give you a few knots. Additionally, you could reduce the size of the nose wheel to be more like the one on the 6/7. With the new engine, you could potentially reshape the front cowl to be more aerodynamic.

Finally, if you were willing to give up a bit on the stall speed, you could shorten the wings a rib. That would decrease drag a bunch and SHOULD only affect your stall speed.

You are on the money except for the stall speed to be light sport
Joe Dallas
www.joesrv12.com
 
I assumed that you wouldn't necessarily be aiming for LSA if you were going EAB, but if you were, shortening the wings would be a bad idea unless coupled with something to offset the reduced stall speed. I know of some things the cherokees do (from a post on the red board) to lower the stall speed, such as different wing tips, vortex generators, or those little tabs that go on the wings.

Additionally, if you wanted to gain a few knots, I suspect you could reshape the canopy a bit. It is quite a bit bulbus, and shortening it could give you a bit of speed. I seem to remember there being more than enough headroom in the 12 I was in, so a few inches there could possibly help.
 
Cool project

As some points for comparison:


It should be noted that the center of mass position on the Rotax is further aft in comparison to the Jabiru due to the gearbox and oil tank. I'd be surprised if the 2200 would be moved 4 inches further forward with regards to the prop flange to maintain the same aircraft C of G.

Cool project. Very interested to see one mounted up, W&B and performance comparison!:)

I think the gearbox moves the cg of the rotax forward
The 2200 is lighter a will use a smaller diameter prop
as the prop speed will be higher.
I think the three to four inches is correct.
Also very interested to see one mounted up.

Joe Dallas
www.joesrv12.com
 
Finally, if you were willing to give up a bit on the stall speed, you could shorten the wings a rib. That would decrease drag a bunch and SHOULD only affect your stall speed.

Wingspan directly affects the power required to fly, and longer is better. Since it's only the excess power available that lets an airplane climb, the climb rate and the service ceiling, already low, will both suffer if the wings are shortened.

This is very, very basic.
 
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Basics...

I may regret jumping into this furball, but I want to summarize the Jabiru idea before this thread gets out of hand.

Jabiru 2200 mounted on a perfectly stock, out-of-box RV-12 airframe.
Jabiru USA is interested in creating a firewall-forward kit for the airplane. This will include engine mount, cowlings, cooling baffles, carb heat, battery box, exhaust, prop, spinner, and more. The 3300 is a more challenging option due to the geometry of the firewall, but will also be considered.

Jabiru 2200 engine costs significantly less than Rotax, is lighter, simpler, burns 3.5-4 gph, and will probably cruise a little slower due to a few less horses. (Slow down and enjoy the scenery through that big bubble canopy.)

Aesthetically, it will stretch the nose a little to make the airplane look more grown-up (Less "cute," more "RV"). You will also have a wood prop turning at 2600-2900 rpm most of the time. It does sound pleasant. Again, a matter of personal preference.

It would be registered as Experimental-Amateur Built. Its max gross weight and flight characteristics all fit the definition of a Light-Sport aircraft, so it can legally be flown by a Sport Pilot or a Private/Commercial Pilot with an expired medical. The builder is free to use any avionics package he or she wants to, because it is no longer bound by Van's E-LSA design limits.

That's it.

PS-- I also work at Jabiru USA. This is what we do.
 
Like I said, cool project and can't wait to see it in the air.:cool::)

For those interested, we have a couple 3300s flying in OZ now with EFI. The carb and mags are retained as backups. Fuel burn, mixture distribution and power are all improved according to pilots testing them and several more systems are on order now. The results surprised me quite frankly.
 
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