CASA 292/14 - Conditions and direction about Jabiru engines

[ieadave]

That is in part (at least) a recognition that there is a legal difference in status: Jabiru ( or specifically, Aerotec, it's engine company

Oscar. Please explain Aerotec for the benefit of this discussion. Who holds the Intellectual Property Rights on the Jab engine?

 

 

[Oscar]

Hi, iedave.

 

Sorry, slightly faulty memory there, it's Avtech, not Aerotech. It's the legal entity that Jabiru use for their manufacturing, so e.g. the TCDS for the type-certificated aircraft and the engines is legally held by it. The IP on the Jab. engine is a complicated issue and really doesn't affect the legal responsibility for the engines.

 

 

[Old Koreelah]

 

 

Some of the 2210 features are attractive, especially the Nikasil bores and castings. The pic they released shows a very different induction system:

 

 

[facthunter]

The "new" cylinder would no doubt permit closer clearances to be used in the piston/cylinder dimensions, which should reduce blow by and hot spots. A still can't work out why the spigotting into the head is so deep. There would have to be some problems with heat transfer in that area unless it's a close fit, making dismantling a bit more complex. Nev

 

 

[Jaba-who]

Hi, iedave.Sorry, slightly faulty memory there, it's Avtech, not Aerotech. It's the legal entity that Jabiru use for their manufacturing, so e.g. the TCDS for the type-certificated aircraft and the engines is legally held by it. The IP on the Jab. engine is a complicated issue and really doesn't affect the legal responsibility for the engines.

So how does Camit fit in - not as the fabricator of genuine Jabiru bits which they pass back to Jabiru - but as the maker of knock-off clones (with some slight variations).

 

I remain totally astounded that Camit are legally able to produce an engine using anything that looks even remotely like a Jabiru engine. Its a completely bizarre situation where one company who has been contracted to build something for someone else is able to build their own version it.

 

Its all very weird.

 

 

[Oscar]

Firstly, the CAE engine is not a 'clone', it (in the 'core rebuild) configuration, is different in most respects with the exception of the shaft and rods. Secondly, you do not know the shared IP situation.

 

 

[David Isaac]

I had always believed there was a shared IP arrangement.

 

 

[Geoff13]

There was a reason that Ian went back to the solid lifter engine and worked from there. If you ask him I am sure he would tell you.

 

 

[jetjr]

A lot of faith being put in new 2210 with just a few going. Thats sure some big changes.

 

 

[Jaba-who]

Firstly, the CAE engine is not a 'clone', it (in the 'core rebuild) configuration, is different in most respects with the exception of the shaft and rods. Secondly, you do not know the shared IP situation.

No I don't that's why I asked.

 

 

[gandalph]

Jabba-who, You are probably asking the wrong people. I doubt that even Oscar knows all the details of the IP agreement that Jabiru and CAMit have, and even if he was full bottle it would be irresponsible of him to share those details here. You should seek enlightenment from Rod Stiff or Ian Bent not from us lesser folk.

 

 

[Jaba-who]

Jabba-who, You are probably asking the wrong people. I doubt that even Oscar knows all the details of the IP agreement that Jabiru and CAMit have, and even if he was full bottle it would be irresponsible of him to share those details here. You should seek enlightenment from Rod Stiff or Ian Bent not from us lesser folk.

Probably but I thought it might be public knowledge.

 

 

[Oscar]

Jw, Gandalph is absolutely correct - I don't know the details and it would not be my place to discuss them even if I did!

 

 

[Jaba-who]

Duly chastised. Climbing back into my box.

 

 

[gandalph]

Duly chastised. Climbing back into my box.

No no no no no! No chastisement at all. I apologise if you read my response as a put down. It was not.

There is a shared IP agreement, and that's about the extent of the public knowledge. As far as I know it relates only to the engines not the airframes. I assume that like most similar agreements it would be commercial-in-confidence.

 

 

[Oscar]

Jw - not meant to chastise at all! The whole story of the Jabiru / CAMit engine development is quite complex - as I understand it - and I am sure it would make for a fascinating study of how there came to be successful Australian companies producing aero-engines from what were, realistically, humble and rather speculative beginnings - it's not as if there was any known path to tread for those guys in the early days!. Seriously, one has, I believe, to admire both Rod (and Phil Ainsworth) and Ian Bent for everything that has been achieved - especially when one takes into account that neither Bombadier nor Textron have managed to actually get a successful aircraft AND engine package for this class of aircraft despite their huge resources and experience.

 

 

[facthunter]

You certainly don't want a monopoly in "suitable" engines for our types of aircraft. It's useful to read the history of Jabiru's engine situation and Philosophy when the original engine makers KFM? went out of business. The whole plane was a package requiring a simple light weight motor and explains the reason why the "easy" fix (fitting the ubiquitous Rotax 912 wasn't the answer. Nev

 

 

[Old Koreelah]

Both Jab and CAMit seem to have viable improvements to the original engine. I'd like to be able to mix and match:

 

Cast heads and barrels, Nikasil bores, belt-driven alternator, and maybe Geoffreywh's symmetrical intake system (post No. 1236).

 

 

[geoffreywh]

Dont forget the dry sump too. Thanks.

 

 

[Old Koreelah]

Dont forget the dry sump too. Thanks.

Probably can't have a symmetrical intake system with that sump in the way.

 

 

[Jaba-who]

I'm not familiar with dual carb systems - a question for the masses. Are dual carb systems typically split to have 1 carb feeding just half the cylinders or do they mix their outflows and feed all cylinders.

 

 

[turboplanner]

I'm not familiar with dual carb systems - a question for the masses. Are dual carb systems typically split to have 1 carb feeding just half the cylinders or do they mix their outflows and feed all cylinders.

You can use them on a plenum chamber or you can use paired plenum tubes or you can use one carb per cylinder on a tuned length tube, which will produce the most power and avoid starving any cylinder.

 

 

[jetjr]

Jabiru are working on dual carb for 3300, one carb feeds each side. Not sure how serious or successful but it looked ok.

 

As with Rotax and other multi carb setups Id say balancing is necessary and a bit tricky

 

Carbs sit higher and use runner, you can actually see it in the 2210 photos i think with induction pipe for third cylinder facing out front forward of engine

 

 

[Old Koreelah]

...you can actually see it in the 2210 photos i think with induction pipe for third cylinder facing out front forward of engine

The 90 degree bend in that pipe wouldn't be conducive to good gas flow. I thought it might be part of a cabin heat system.

The photo also shows the little springs used to secure the ram air ducts. Why don't they just use a fence around the engine like everyone else?

 

 

[facthunter]

It depends on how the pulses of the cylinders happen. One on each side of a flat four is not good, as it's suck suck pause pause. This is the set up on the Rotax912. If you examine the crucifix up draught on the Continental fours it's pretty good from the distribution point of view. A flat six could be even enough depending on the crankshaft and firing order to have one carb each side. Smooth flow on branched manifolds looks good but is notoriously hard to get even mixtures over a varied flow. Power/ rpm range. The oil sump is in the way of updraught manifolding. It's also a structural part of the motor and a deep one is weaker as it's like a box with no top on it and no bracing. Nev