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Jabiru mixture

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Go back to the starting point of this forum for what I think. I haven't talked to Jabiru, but I think the April 1 theory could be correct.

Spacesailer. How do you fly at 100mmph? Surely micro miles per hour is too slow to support flight

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5 hours ago, turboplanner said:

Forget the engines; what are your thoughts on the Automotive Mixture Control System? There's a description and a mockup here: https://jabiru.net.au/    Scroll down the main page.

 

Sounds a bit odd to me -  Does that mean you set your carb to deliver a high fuel mixture & the gizmo then corrects it by admitting more air? The fail safe back to carbi will then run rich for how long? 

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. I'm not much the wiser from anything there.

    . As said you can only lean an already rich mixture and also the manifold (vacuum? ie suck) is higher at low throttle openings. (not mentioned anywhere I can seeing the bumph. but it's something to take into account .I agree getting even mixtures to multiple cylinders is a difficult task from  a single point "anything". "Gami" injectors did this with the common old mechanical injection systems  quite satisfactorily and you don't need an auto system as it's a totally different environment it's tailored to work to with multiple and rapid throttle changes at mostly low power and lots of NO power (idle) with short periods of high power.. I question whether they are actually as trouble free as some allege. They are certainly not easy to troubleshoot when they are playing up.  Nev.

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So my real questions are with the GEN 4, and where do you get real information from.

1. How many gen 4 engines have been put into aircraft to this date. Number IS ?

2. How many high  hour  engines  are operating without failure  say at 500 , 1000, 1500?

3. If any failures what are they and WHEN??

 

Anything else is pure smoke and mirrors or guess work here.   

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3 hours ago, SSCBD said:

So my real questions are with the GEN 4, and where do you get real information from.

1. How many gen 4 engines have been put into aircraft to this date. Number IS ?

2. How many high  hour  engines  are operating without failure  say at 500 , 1000, 1500?

3. If any failures what are they and WHEN??

 

Anything else is pure smoke and mirrors or guess work here.   

If you're looking at cost of life analysis, for example if you were running a flying school, you would be looking for this sort of information albeit probably using 1000, and 500 increments to 2500.

If you're looking at the reason for the CASA Instrument you'd be asking how many forced landings per year, bearing in mind the issues reported publicly, although generally related to combustion chamber were random, some reported to have occurred on return from the factory. 

 

Because the issues were at random hours the telling evidence will be the record virtually from zero, becoming more compelling with every 500 hours.

 

 

 

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3 hours ago, turboplanner said:

If you're looking at cost of life analysis, for example if you were running a flying school, you would be looking for this sort of information albeit probably using 1000, and 500 increments to 2500.

If you're looking at the reason for the CASA Instrument you'd be asking how many forced landings per year, bearing in mind the issues reported publicly, although generally related to combustion chamber were random, some reported to have occurred on return from the factory. 

 

Because the issues were at random hours the telling evidence will be the record virtually from zero, becoming more compelling with every 500 hours.

 

 

 

No Turbo don't twist my post it is a fair and straight question -  I am looking at the gen4 engine, how many are flying now, and hours on them, and if any problems as per my post above. Shpuld not Raa have all these numbers as well?

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2 hours ago, SSCBD said:

No Turbo don't twist my post it is a fair and straight question -  I am looking at the gen4 engine, how many are flying now, and hours on them, and if any problems as per my post above. Shpuld not Raa have all these numbers as well?

You could contact RAA, but I haven’t seen data collected for general use in analysing  life cycle costs. I’ve always had to interview owners one by one and build a spreadsheet, and there are always some apples and pears issues to discard.

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16 hours ago, SSCBD said:

So my real questions are with the GEN 4, and where do you get real information from.

1. How many gen 4 engines have been put into aircraft to this date. Number IS ?

2. How many high  hour  engines  are operating without failure  say at 500 , 1000, 1500?

3. If any failures what are they and WHEN??

 

Anything else is pure smoke and mirrors or guess work here.   

SSCBB, these are fair questions that I feel need to be asked.

Maybe someone might have to ask Mr Jabiru himself and whilst they are at it confirm if this original thread is a 1 st April hoax or not.

Are there any CASA standards or testing regimes these engines go through before they are used for aviation use, especially commercial use, flying schools ?

 

 

 

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Posted (edited)

All nice ideas, Bald Eagle. If implemented, who would consider manufacturing an aero engine? The market is tiny, and now you want to greatly incease the set up costs.

Edited by Old Koreelah

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you sort of imagine that the Gen 1,2 and 3 engines will continue to hurt Jabiru's reputation for another 15-20 years

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On 4/14/2019 at 5:25 PM, turboplanner said:

If you're looking at cost of life analysis, for example if you were running a flying school, you would be looking for this sort of information albeit probably using 1000, and 500 increments to 2500.

 

Just helped replace the Rotax 912 in the club aircraft at 1500tt. Sold the old engine with 500 to run, our capital cost worked out at $12 per hour. The new owner even if he takes the engine to the tip at 2000 is up for $17 per hour with a lot less capital outlayed, I don't think this is expensive. Haven't had any previous 912 experience but the plumbing was very simple.    

20190420_102756.jpg

 

Jab 200/400 with a 915 at 700kg MTOW would be an absolute world beater.

Edited by Thruster88

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 Time will tell with a lot of this..  In service experience is always important  but the way they are used is very variable . I have no reason to think the New Jab engines will be more of a problem than the earlier ones. and there's quite a chance they will be much better .. To regard 2,500 hours as  a time to consider and compare is a bit of an EXPECTATION, of a fairly high order as practically no IC  aircooled aero engine goes that far and when and IF it does it's  how it's serviced  and operated becomes of the most significance. It won't go that long without attention to the Valves and you shouldn't expect it to..Nev

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7 minutes ago, facthunter said:

 Time will tell with a lot of this..  In service experience is always important  but the way they are used is very variable . I have no reason to think the New Jab engines will be more of a problem than the earlier ones. and there's quite a chance they will be much better .. To regard 2,500 hours as  a time to consider and compare is a bit of an EXPECTATION, of a fairly high order as practically no IC  aircooled aero engine goes that far and when and IF it does it's  how it's serviced  and operated becomes of the most significance. It won't go that long without attention to the Valves and you shouldn't expect it to..Nev

There have been plenty of lycoming's that have done 2500+ I know of one personally. The 0-235 has had  a 2400 tbo  for a long time. That's the 152 engine, sure they may have problems but they nearly all ways make it back to  the shop.

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I don't know of any that make over 2.000 hours without top work The basic engine does that FIGURE often. They have tried hard to get the valves etc to go for that time but it's unusual (if ever) and there are often bore rust problems in little used engines.. or engines left unused for even short  times and not inhibited. Having a TBO of 2500 hours doesn't say it won't need top work during that time. You do a compulsory Comp. check every annual or 100 hours and continued use is subject to that being satisfactory. Nev

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