DonRamsay Posted November 27, 2014 Posted November 27, 2014 Oh yea ok. Most pilots dont even notice the rough range, and as you say, if it not in a 'spot' where your likely to leave it, its not a concern.. Hmmm, It is hard to tell if someone is being a little "funny" in just black and white text. Just in case there was a slight tone of well meant sarcasm there Motz, we do keep our L2 advised of the rough running just in case it happens to be something more life threatening. Engine is smooth as at >5,000 rpm.
motzartmerv Posted November 27, 2014 Posted November 27, 2014 No don. No sarcasm there at all. I wouldn't joke about something like that. :) 1
pylon500 Posted November 27, 2014 Posted November 27, 2014 Regarding rough running with 912's, you'll probably find it occurs as you throttle down through the 'zero thrust' rpm. At this point there is no load through the gearbox and the crankshaft impulses will excite the backlash in the box. Below that, the aircraft is pushing the prop.
DonRamsay Posted November 27, 2014 Posted November 27, 2014 Don You still have to watch things on the 912 They have a dog's breakfast cooling system and rubbers that crack on the Carbs and carb balance difficulties. True Nev. At our last 100 hourly, we went through the 5 year total rubber replacement on our 912. It was reassuring that the rubber that came off looked as good as the rubber going on except of course for the carbies. Not everyone want's a water cooled system because air is there and you don't need radiators, hoses pumps and some way of regulating the temps. You SAY certain things are not acceptable in this day and age. They sell cars on the basis of the owner never lifting the bonnet and half the time you can't even find a dipstick. It doesn't logically follow that we should, in our aero engines , just accept the view that it is the best for us in our aircraft. They sell all things mechanical (excluding aero engines) on that basis nowadays and the general level of understanding of machines has dropped close to zero. Young pilots have it thumped into them that they cannot afford that attitude if they are planning on leaving the ground and have a bit more awareness but, without a few courses, they are not in a position to be trusted maintaining an aircraft engine beyond the most basic items. Obviously, I'm not talking about the bulk of RA-Aus grey-beards who do have an affinity with and some experience working on engines. But, the next generation? I wonder. Do we apply the same logic to the airframe and tyres and brakes? No you don't you replace and inspect components. Same as in a Jabiru motor. How many people these days could do (or do do) a simple pad inspection let alone change on their cars? Not saying they couldn't be trained to but most have never done it or been shown how to. Do you want the Rotec Radial to be subject to the same criteria? because it may need the same attention. If Not Why not? and we go on from there do we? No, these are heritage engines not mainstream. The only people who buy them must appreciate that. Like as if you bought a T model Ford the engine is not going to have to meet 21st Century roadworthy standards (other than for glass). We are dumbing down things is we go this way. Get the information out about the DETAILS of the problems with Jabiru and let the people and the companies decide what the market is. You make your own luck to a great extent, by your approach not the engine you fit. No one's forcing anybody to buy any particular engine. I HOPE Nev. Not forcing you to buy but certainly restricting your options. I've made the personal decision that Jabiru motors are not for me. My risk assessment and my choice. Everyone should do that but many are just attracted by the lower up front cost and think they can manage the reliability risks. Fact is some can and some don't. It is a pity Jab don't offer the Rotax option for those that are happy to spend the money up front because for me it means I can't buy a J230 which is probably the best aircraft in Australia for general purpose touring. 1
DonRamsay Posted November 27, 2014 Posted November 27, 2014 Microman if we did a 912 $3000 overhaul our engine would be on condition for the next 1,500 and potentially not able to be used in a flying school. This is one of the frequent arguments here as the cost of the 912 full overhaul is circa $20,000 whereas a new one is not that much more than this. Jab engines cost closer to $14k, plus overhaul then at 2,000 hours they receive a full overhaul. In "theory" this works out much cheaper than the Rotax. Deborah, If you were to start with the cost of a new engine and work out the cost of, say, 2,000 h0urs over 10 years to a scrap value of the engine I would be amazed if a Jab engine were the lower cost per hour. If what I've read and have heard of Jabiru engines (not authoritative), you would have to include the price of two Jabiru engines and two significant overhauls plus attention every 25 hours or so. Add on the oil burned and incidentals plus ANs for through bolts and the like. Then do the same for a Rotax 912ULS. You would have the rubber replacement, a gearbox overhaul, possibly but not necessarily a sprag clutch and possibly (probably) carby overhaul. The Rotax donk in reasonable condition at the end of 2,000 hours would be worth more than $5,000 so deduct that. I don't know what a Jab engine is worth at the end of 2,00 or even 1,000 hours (twice) but you'd need to deduct that as well. No question Rotax spares are expensive and you can't do the gearbox or engine overhaul yourself. Perhaps that's the key, if you are a L2 you might with a lot of your own time be able to operate a Jab engine for a moderate cost and with acceptable reliability - I know L2s that do. But, if all your maintenance except oil and spark plug changes are done by a L2/LAME then I think you'd be in front with the Rotax. But, clearly as somebody said above, this is all off thread and we really should get back to the thing we all agree on - bagging out CASA for an unreasonable response to the Jab engine issues. 1 1
Rolf Posted November 27, 2014 Posted November 27, 2014 The question was asked of me re sending various people solo in a Jab. . I would be more concerned about their flying standard than the engines reliability. Nev Sorry Nev I admire all your knowledge you bring to this forum. But facthunting is pretty useless if You go into denial accepting them. I experienced 2 J230 engine failures during my training 1 shortly before the takeoff roll. If it had happen 20 sec later I am not so sure what the outcome would have been even with my instructor by my side. By the way just for the record 1 engine failure happened only a few hours after the engine came back after a rebuilt from the factory. 4
jetjr Posted November 27, 2014 Posted November 27, 2014 The L2 vs self maintained is a good point Don, sure makes a big difference in costs No doubt CASA will review this too. Id be onterested in 914 purchase and service pricing Also need to watch the life issue wih Rotax engines, plenty of private owners going to run out of time well before 2000 hrs 1
bexrbetter Posted November 27, 2014 Posted November 27, 2014 Id be interested in 914 purchase and service pricing 2 years ago in Oz, I was standing next to a 914 being fitted to a plane and then the total price was mentioned for everything to the last nut and bolt .... $37,000. I genuinely thought I heard wrong. I nearly fainted, WTF is wrong with some of you blokes. 5
Geoff13 Posted November 27, 2014 Posted November 27, 2014 2 years ago in Oz, I was standing next to a 914 being fitted to a plane and then the total price was mentioned for everything to the last nut and bolt ....$37,000. I genuinely thought I heard wrong. I nearly fainted, WTF is wrong with some of you blokes. Less than twice the price of a 6 cyl Jab for more power. But apart from that what price the safety of your family. In my case price is the last consideration. If I can be convinced that a Jab is safe then I may buy one, but if I were not convinced they were safe no price saving in the world would get me behind one. In my case the jury is still out on that issue. I do think they can be built to be safe, but I am not convinced that Jabiru are doing that yet. Cheers Geoff13 4
DonRamsay Posted November 27, 2014 Posted November 27, 2014 Bex, that is about the current price. Around $27k for the injected 912 and $23k for the 912 ULS. Interestingly, if you started with a new factory built J230 for less than $100k and the factory agreed to put in a 914 instead of the 3300, you'd have a damn good aeroplane for around $120k - a lot less than your typical Euro import. There would be a big line up for such an aircraft. And if you went with the 912 with an IVP prop you'd have 3300 performance at the operating cost of a 912. So much potential - so little potential realised :-( 2 4 2
bexrbetter Posted November 27, 2014 Posted November 27, 2014 But apart from that what price the safety of your family. In my case price is the last consideration. Geoff, I 100% appreciate your comment, but it does not remove in anyway the fact that many people just don't have that sort of money. Makes me hope and support CAMit to a decent result even more. 1 3
Guest Maj Millard Posted November 27, 2014 Posted November 27, 2014 The 912 can be more efficient and more powerfull because a greater range of prop combinations are possible......there's a lot in the right prop....
deadstick Posted November 27, 2014 Posted November 27, 2014 Current 3300's are almost 130hp. The 914 is 115 for 5 minutes. They are not the same "power." Hi, where are you getting these figures from? 1
bexrbetter Posted November 27, 2014 Posted November 27, 2014 What about at 5000ft? Jabiru = 110 Rotax = 115 1 1
nong Posted November 27, 2014 Posted November 27, 2014 Would you send your horny teenage son up in one solo? Yes. I did.
jetjr Posted November 27, 2014 Posted November 27, 2014 Not as concerned at 5000 ft Its 0-800 ft asl Im needing extra 15 hp Props cant make power, if your talking IFA then is heaps more money and weight. GA props, if you have set fine for heavy take of is it not going to perform at cruise Anyway all that means is IFA on 3300 is going to be better still By the way what does a 914 with IFA cost and weigh? $50K?? Dont forget plenty of Jab 2/430 are Ok to 700 or 750 kg, 115 hp isnt doing very well with that behind it. Dyno runs on CAE 3300 see over 128 hp ive heard 1
Keith Page Posted November 27, 2014 Posted November 27, 2014 Good idea, but be careful, CASA could be watching just waiting to pounce What have you got to hide? Regards KP.
vk3awa Posted November 27, 2014 Posted November 27, 2014 Well it is now the 28th.......Any news as to whether I can take a passenger in my aircraft today or not? 1
Guest Maj Millard Posted November 27, 2014 Posted November 27, 2014 The 912 can be more efficient and more powerfull because a greater range of prop combinations are possible......there's a lot in the right prop.... No props don't make power...but they sure as hell turn it into thrust !...power alone doesn't get us anywhere.
Guest Maj Millard Posted November 27, 2014 Posted November 27, 2014 Well it is now the 28th.......Any news as to whether I can take a passenger in my aircraft today or not? I've heard there is a meeting with CASA at 4PM. I'm sure Michael Monck will give us any news soon as he feels its appropriate.
dazza 38 Posted November 27, 2014 Posted November 27, 2014 Well it is now the 28th.......Any news as to whether I can take a passenger in my aircraft today or not? I would just keep flying with a pax until you are informed otherwise. 2 1
planesmaker Posted November 27, 2014 Posted November 27, 2014 Jetjr I invite you to come for a ride in my j400 at gross 700kg I think you will be very surprised. Tom 1
Guest Ornis Posted November 27, 2014 Posted November 27, 2014 Cost is relevant for private ownership but it is completely irrelevant to public safety. You don't do the wrong thing to save money. And that's the crux CASA is addressing. Young people and their parents see what looks like an aeroplane and they assume it has an aeroplane engine, which they kind-of-know must be safe. They're promised cheap training. What could be wrong? The mystery is: Some people are claiming a good run with Jabiru engines. I have never met one. Is this just statistics, just as someone wins Lotto but not me, or you? Part of the answer may be at what point in the development you made your purchase. If you have a Jabiru engine that reached 2000 hours you won Lotto.
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