Oscar Posted September 15, 2015 Share Posted September 15, 2015 Superficially what you say is right but the Jabiru while looking like a conventional flat aircooled engine is built an a few ways quite different from the "standard" aviation engine. UL is probably closer but better than the ConLyc designs. Nev The Jab. engine has a lot of good points - simplicity being one of the major ones, as well as low weight allowing strength to be added to airframes within the mandated limits for MTOW and stall speed - both of which have, in reality, no direct link to real-world operating. They are both figures pulled out of a hat as a lazy (and frankly, a bloody stupid) way of attempting to generate a 'class' of aircraft, when a simple :' no more than 2 people / 150 kts cruise / piston engine with fixed-pitch prop and fixed gear' would have been completely sufficient. Maybe add 'Take-off and land on a 400-metre strip", to ensure they did not become ridiculously optimised to one type of operation. The Jab. engine's Achilles heel has always been detail design problems and an intransigent attitude from its designer to accepting improvements, and frankly, very rudimentary attention paid to cooling efficiency design and effective engine management reporting installation. Despite that, Jab. engines have served many, many careful and mechanically sympathetic owners and operators faithfully - and that includes FTFs that develop an intelligent approach to engine management. CAMit has spent years researching the 'detail design issues' and is (in my opinion) in the box seat to utilise that expertise to improve on the Jab. basic engine. Recent events in the commercial relationship between CAMit and Jabiru will, in all probability, see further changes by CAMit with further improvements on certain aspects of the basic Jabiru design, and work on cooling effectiveness design is also ongoing. CAE engines will, inevitably, trade off supreme light weight for reliability compared to Jab engines, but I believe even with that penalty, they will be highly competitive on price+performance+reliability for this class of aircraft. No. CAMit won't topple Rotax - no way. But the CAE engine has the potential to be a very serious contender in the U/L aircraft class market. 1 3 1 Link to comment Share on other sites More sharing options...
Oscar Posted September 15, 2015 Share Posted September 15, 2015 I just watched Tony Abbotts last press conference as PM.......It was inspiring.....I felt for him and got a feel for the man as he is, not as his advisors and slogan writers have parroted through him......What a shame that was hidden from us! Andy - I have to disagree. That Press conference was entirely scripted with more than 12 hours of time for his minders to develop the response. However, one's own response to Abbott is completley incidental to our interests as Aviators - what I want to see is a Minister for Transport who will kick CASA right up the backside and get changes done - and Truss is, I fear, not that person, based on his performances over the years. Neither did Labor do anything useful, let me quickly say. It would be nice to think that we might get a Minister with some intelligence into the Transport role, but I am certainly not holding my breath. 2 Link to comment Share on other sites More sharing options...
fly_tornado Posted September 15, 2015 Share Posted September 15, 2015 Oscar, Jabiru and Camit are now splitting that market for an agricultural aircraft engine. Link to comment Share on other sites More sharing options...
Oscar Posted September 15, 2015 Share Posted September 15, 2015 Oscar, Jabiru and Camit are now splitting that market for an agricultural aircraft engine. You are so monumentally ignorant in the comment that either engine is 'agricultural', that it beggars belief. Link to comment Share on other sites More sharing options...
Guest Maj Millard Posted September 15, 2015 Share Posted September 15, 2015 Superficially what you say is right but the Jabiru while looking like a conventional flat aircooled engine is built an a few ways quite different from the "standard" aviation engine. UL is probably closer but better than the ConLyc designs. Nev The big difference being of course that Lycoming, Continental and Rotax use cast or forged alloy cases while Camit and Jab use billet alloy. Link to comment Share on other sites More sharing options...
Oscar Posted September 15, 2015 Share Posted September 15, 2015 Which is completely irrelevant to the reliability or performance of the engines, other than Jabiru / CAMit engines do not develop cracking. Link to comment Share on other sites More sharing options...
Guest Andys@coffs Posted September 15, 2015 Share Posted September 15, 2015 <cough> Fret about it though! <cough> Link to comment Share on other sites More sharing options...
eightyknots Posted September 16, 2015 Share Posted September 16, 2015 Oscar, Jabiru and Camit are now splitting that market for an agricultural aircraft engine. I haven't seen a CAMIT or Jabiru engine used in any crop dusting plane. Link to comment Share on other sites More sharing options...
fly_tornado Posted September 16, 2015 Share Posted September 16, 2015 I was reffering to the magneto/carb setup. Everyone else can see that FADEC is the key selling feature now. Jab and Camit are selling to the home builder who wants something he can tinker with and improve Link to comment Share on other sites More sharing options...
facthunter Posted September 16, 2015 Share Posted September 16, 2015 You have your views ft, and I doubt you will change them. Are they based on experience? An aeroplane carburettor could be one of the simplest devised and still work well if manual mixture control fitted .A floatless one would be safer or a mechanical injection system to each cylinder. Been done before. Simple and owner serviced.. Nev Link to comment Share on other sites More sharing options...
gandalph Posted September 16, 2015 Share Posted September 16, 2015 The big difference being of course that Lycoming, Continental and Rotax use cast or forged alloy cases while Camit and Jab use billet alloy. Link to comment Share on other sites More sharing options...
jetjr Posted September 16, 2015 Share Posted September 16, 2015 FADEC appears to add ~ $10K to the price. At this point only slim fuel savings to be seen Im guessing any of the 120hp euro options will shortly be double the price a new 3300 CAE. Once you include IFA prop and setup Link to comment Share on other sites More sharing options...
fly_tornado Posted September 16, 2015 Share Posted September 16, 2015 Rotax are quoting a huge fuel saving over a 3300 something in the order of 16% Link to comment Share on other sites More sharing options...
jetjr Posted September 16, 2015 Share Posted September 16, 2015 Yeah, quoting for what engine? The one which doesnt exist yet? You can save more than that by slowing down, hardly huge. That would take around 1300 hrs to even out and your money is spent for 20+ years. Im not saying FADEC and Rotax are bad things, they are not. Just the value is debatable. 1 Link to comment Share on other sites More sharing options...
Guest Andys@coffs Posted September 16, 2015 Share Posted September 16, 2015 Rotax are quoting a huge fuel saving over a 3300 something in the order of 16% And for the recreational aviator who flys that average of 50hrs a year will only take 19 lifetimes in fuel savings to pay for the delta in cost between the 2 different engine types.....noting always that the more expensive of the 2 engines has an elapsed engine life of 10 years........ The cheaper one, assuming you get one that lives that long has no such elapsed years life...... If we were honest and applied sound financial analysis to our aviation decision making then none of use would have taken it up at all...... Its not that I doubt your claim, or indeed the one who originally made the claim, what I doubt is the real world usefulness of such a claim Link to comment Share on other sites More sharing options...
Oscar Posted September 16, 2015 Share Posted September 16, 2015 Rotax are quoting a huge fuel saving over a 3300 something in the order of 16% WOW!. The average private usage of a RAA-class aircraft is around - or less than - 80 hours/year. At say 20 litres/hour / 75% cruise for a 3300, that equates to 1600 litres of fuel per year.. A saving of 16% on that, is 256 litres. At an average cost of $1.50/litre for 98 Ron Mogas, that's a saving of about $400/year. Of course, we are talking about the comparison between a 100 hp engine - the 912 iSc, to be comparable with the Jabiru 3300 certified 120 hp engine as used in the 230/430 series, not some cramped featherweight Euro device. 16% fuel savings for 20% less hp doesn't seem such a magnificent trade-off to me. But: let's look at that with reference to the extra cost of the Rotax offering the additional 16% fuel economy of the Rotax with FADEC system, at only (another conservative estimate) $10k. It will take 25 years to break even. But, of course, there is an age limit on Rotax engines, beyond which they have to be replaced. A busy FTF averages around 400 hours/year for its training fleet. So that 25 years is reduced to about 5 years. But: the 2000-hour life on the engine acceptable for 'training/hire' use is now expended ( for both) so for the Rotax replacement, just as you get your extra money back from the fuel savings, you have to spend the extra $10k on a new engine vs. the 3300. Looks to me as if the $$ savings from the economy, is effectively zero in real costs. And the maintenance costs of the comparable airframes in FTF usage between a Jabiru/CAMit engined aircraft and any Rotax-powered aircraft are proven to be in the favor of Jabirus - since 60%+ of the FTFs use Jabirus. So: just quoting 'fuel 'economy' figures is a complete load of tripe for comparing the REAL operating costs. But - let me not dissuade you from constructing a convincing argument that buying a Rotax 912 iSc that delivers 20% less hp is is better economy in $$ terms than buying a Jabiru/CAMit 3300. Show us the equivalent aircraft powered by a 912 iCs to a Jab. 230 D - the ASTM certified ones - that use the 3300 engine. Come on, lad: convince those of us with effective cognitive capability, that you have a cogent argument. Link to comment Share on other sites More sharing options...
Geoff13 Posted September 16, 2015 Share Posted September 16, 2015 WOW!. The average private usage of a RAA-class aircraft is around - or less than - 80 hours/year. At say 20 litres/hour / 75% cruise for a 3300, that equates to 1600 litres of fuel per year.. A saving of 16% on that, is 256 litres. At an average cost of $1.50/litre for 98 Ron Mogas, that's a saving of about $400/year. Of course, we are talking about the comparison between a 100 hp engine - the 912 iSc, to be comparable with the Jabiru 3300 certified 120 hp engine as used in the 230/430 series, not some cramped featherweight Euro device. 16% fuel savings for 20% less hp doesn't seem such a magnificent trade-off to me.But: let's look at that with reference to the extra cost of the Rotax offering the additional 16% fuel economy of the Rotax with FADEC system, at only (another conservative estimate) $10k. It will take 25 years to break even. But, of course, there is an age limit on Rotax engines, beyond which they have to be replaced. A busy FTF averages around 400 hours/year for its training fleet. So that 25 years is reduced to about 5 years. But: the 2000-hour life on the engine acceptable for 'training/hire' use is now expended ( for both) so for the Rotax replacement, just as you get your extra money back from the fuel savings, you have to spend the extra $10k on a new engine vs. the 3300. Looks to me as if the $$ savings from the economy, is effectively zero in real costs. And the maintenance costs of the comparable airframes in FTF usage between a Jabiru/CAMit engined aircraft and any Rotax-powered aircraft are proven to be in the favor of Jabirus - since 60%+ of the FTFs use Jabirus. So: just quoting 'fuel 'economy' figures is a complete load of tripe for comparing the REAL operating costs. But - let me not dissuade you from constructing a convincing argument that buying a Rotax 912 iSc that delivers 20% less hp is is better economy in $$ terms than buying a Jabiru/CAMit 3300. Show us the equivalent aircraft powered by a 912 iCs to a Jab. 230 D - the ASTM certified ones - that use the 3300 engine. Come on, lad: convince those of us with effective cognitive capability, that you have a cogent argument. Your figures are flawed, Jab recommend using Avgas whereas Rotax recommend Mogas so you really need to use those costs. I have no real opinion about the rest of it other than I am comfortable with my decision to remove the Jab motor from my plane and fit a Rotax. 1 Link to comment Share on other sites More sharing options...
planesmaker Posted September 16, 2015 Share Posted September 16, 2015 If only Jabiru would fit 912s to their j230 they would be on a winner on the world scene! My 2 cents 3 Link to comment Share on other sites More sharing options...
jetjr Posted September 16, 2015 Share Posted September 16, 2015 912is on a j170 maybe, would make a great trainer but it isnt going to happen. Once you get to that price point theres lots of good options Link to comment Share on other sites More sharing options...
planesmaker Posted September 16, 2015 Share Posted September 16, 2015 Yes a j230, the best airframe that jab produce. Link to comment Share on other sites More sharing options...
Oscar Posted September 16, 2015 Share Posted September 16, 2015 Your figures are flawed, Jab recommend using Avgas whereas Rotax recommend Mogas so you really need to use those costs. I have no real opinion about the rest of it other than I am comfortable with my decision to remove the Jab motor from my plane and fit a Rotax. OK, fair point. I just looked up the latest figures for Shell 100LL, that of course varies by location (as does Mogas) but a rough average price at a regional airport decently accessible to RAA aviation is around $1.80/litre ( Caboolture, top of the list, 1.79.9, Sept. 12 figures from the Shell list at: http://www.ppp.shell.com/prices.aspx I don't see Mogas 95 (minimum for Jabs, 98 preferred, though personally I believe 95 is the better, safer choice) for much less than about $1.40 on average. So, let's say 100LL on average $0.40/litre dearer. That adds up at a higher cost over 256 litres difference of about $102/year. Not sure that that is really going to knock the ball solidly into Rotax's court as a major factor... I'm not trying to promote Jab/CAMit engines to those who prefer Rotax, but I do think that the arguments pro and con each brand should be based on a sensible appraisal of the facts pertaining to each - and especially, the suitability of each for the airframe and intended usage. 1 Link to comment Share on other sites More sharing options...
K-man Posted September 16, 2015 Share Posted September 16, 2015 OK, fair point. I just looked up the latest figures for Shell 100LL, that of course varies by location (as does Mogas) but a rough average price at a regional airport decently accessible to RAA aviation is around $1.80/litre ( Caboolture, top of the list, 1.79.9, Sept. 12 figures from the Shell list at: http://www.ppp.shell.com/prices.aspx I don't see Mogas 95 (minimum for Jabs, 98 preferred, though personally I believe 95 is the better, safer choice) for much less than about $1.40 on average.So, let's say 100LL on average $0.40/litre dearer. That adds up at a higher cost over 256 litres difference of about $102/year. Not sure that that is really going to knock the ball solidly into Rotax's court as a major factor... I'm not trying to promote Jab/CAMit engines to those who prefer Rotax, but I do think that the arguments pro and con each brand should be based on a sensible appraisal of the facts pertaining to each - and especially, the suitability of each for the airframe and intended usage. I couldn't believe that price as I don't think I've ever paid less that $2.00 for AvGas, at least in recent times.What you missed was ... Note: For all domestic flights within Australia, please note that (as per Government Legislation, effective 01 July 2014) Excise of 35.56AUD/1000L for both Jet fuels and Avgas, as well as 10% Goods and Services Tax (GST), must be added to the listed price. That adds another 20c per litre to your calculation. Flying in the major city areas may give you cheaper AvGas but once you fly into remote areas the price of AvGas can go through the roof whereas MoGas is much cheaper. Birdsville is a great example of that. Link to comment Share on other sites More sharing options...
Oscar Posted September 16, 2015 Share Posted September 16, 2015 Aha - I certainly didn't know about the extra imposts, the table I found did not indicate either extra charge, but I should certainly have figured it was GST+ at least. However, even at an average of $0.60/litre dearer for the 100LL and rounding up a wee bit, let's say the Mogas savings for the Rotax comes to $600/year for 80 hours flying. that makes it a bit over 16 years to get to $10K of savings: 1280 hours total. Link to comment Share on other sites More sharing options...
facthunter Posted September 16, 2015 Share Posted September 16, 2015 And by then the engine is elapsed on a time basis. Nev Link to comment Share on other sites More sharing options...
jetjr Posted September 16, 2015 Share Posted September 16, 2015 Mogas in regional areas becomes more and more risky too. Its often much older and prone to problems. For myself, and my depressingly low flying hours in recent times, Mogas would just be yellow goo in the tanks by now. Higher hours and fresh fuel it may be OK. Plenty of Jabs run mogas, with the lower price comes risk. I think the average aircraft hours is lower than 80 per annum too. Oh and that $0.36 isnt really a cost, we get it back in services etc from CASA............ The similar tax on Mogas goes to general govt funding.....charter flights for pollies. 1 Link to comment Share on other sites More sharing options...
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