Diesel V8 flys
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But that will put Jaba out off bussiness. See what the future holds. Think Avgas will be around for a long time yet.
It will?
I think all of GA can disappear along with all the LAME's, the airlines get robots to fix their jets……..and it will have zero affect on my business. When all food production, water, sewage, power generation, road building, construction materials, mining, brewing, hospitals, <keep adding every industry sector you can dream of> and all the other industries in between disappear, then I am in trouble.
Just a quick look at Diesel Aviation engines and fuels, the calorific values, mass etc. For the comparison lets look at the pick of the Diesels so far, the SMA 230HP in the C182, and a typical GA engine the 260HP IO540.
Remember the Diesel burns Jet A, with a SG of about 0.81 and 128K BTU's / gallon. Avgas is about 0.71 and 114K BTU's / gallon. Lets for arguments sake assume tank volume is not an issue, because you can get more kg of Jet n the same tank and MTOW is, the Avgas KG=160.56K BTU's. The Jet A is 158.0K BTU. The Avgas has about 1.6% more per kg.
BSFC, the key diesel strength is impressive and the SMA quoted figures are 0.36 and compared to say a typical IO540 at 0.39-0.395 or even a TNIO550 at 0.385 you can say it is roughly 10% better. If you look at the lower compression engines such as many TC's then the BSFC gap is even greater.
I have not compared the SMA to any lower compression TC engines because while you could argue the SMA is turbocharged, and it is….it is not comparing real world apples with apples as it has to be TC just to match the N/A 540/550 as is the nature of the beast. In fact that is also its achilles heel.
Next is the weight of the power plant 455 lbs to 410 lbs, naturally the SMA is heavier, and this will affect the fuel payload assuming all other things are equal, as to what the net affect is will depend on the mission.
One advantage is the SMA will hold its HP up to 10,000' and that has a TAS benefit as the IO540 will be around 60-65% of its power at those kind of heights. The squared law comes into affect of course so it is not going to be quantum leaps faster. The C182 is about 11% faster for the same fuel flow, so there is a lot to like about it.
The downside is the cost, however the fuel is roughly 11-13% at the Shell pumps around Oz more for Avgas so that can have an impact when there is a 10% less burn. Makes the MPG about 24% more in dollar terms.
There is a lot to like, but this is a niche machine for one, and it is not going to be across the fleet any time soon. The STC process alone to convert the fleet is prohibitive for a start. Let alone all you folk who want EO's even with the STC.
The other down side is many GA pilots have had many intake leaks……and most never know about it (but that is another story) and this is my main concern. Look at the lovely picture here http://www.smaengines.com/IMG/pdf/Fi...Engine_BAT.pdf and ask your self what happens with those pretty blue couplings when all is not 100% right. On your typical IO540 or even a TC/TN engine you have a manageable albeit non conforming engine. The SMA you have silence.
Pick ya poison!
Disclaimer: Numbers quoted are approximates and all is "back of beer coaster" calculation and analysis. In true PPRUNE tradition ;-)
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Most folk don't know they have an induction leak. Where is your data on that. That's another I pull that out of the blue sky. What a crock. Induction leak is the quickest thing you will know about may take some time to find where it is. So Jaba are you a master of every thing I take it. Ga will always be around. Maybe be not for private but there still a lot of work out there besides private work.
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Hempy….myself being a conservative kind of guy would opt for LOP, but I can imagine some out there telling us ROP is the only way to go 
You are funny whoever you are
You are funny whoever you are
The real problem is that aviation in general and general aviation in particular wants to keep itself mysterious and elite. If it were democratised, like the auto industry, it would be able to generate the sales and use volumes that would bring prices down. Unfortunately, between the regulators and the epaulette brigade, there is some resistance to doing this. Sad really, because for point-to-point transport it is pretty efficient on a passenger-mile and infrastructure cost basis.
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I don't have to grasp at any straws at all. The point is I'm making is that people like to have a dig yet they don't have the qualifications to have it. Like he has told me I've and we all been issuing M/R we on yet he has never issues one. He also dosnt understand a burnt valve and how it happens.
No one besides the regulator dosent won't GA. The damage is the legal profession like it or not. When tcm can make a whole new engine from paper with the cost of their insurance each year there lies the main proplem.
No one besides the regulator dosent won't GA. The damage is the legal profession like it or not. When tcm can make a whole new engine from paper with the cost of their insurance each year there lies the main proplem.
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Oh and then all what I've been taught learnt and found out myself is all wrong because Jaba and his clones say so. To be told I was dangerous was quite liable lucky I not pressured I. That way to have taken action for that coment. But what I've been told is true after the acciedent in Melbroune this week some things may be up for change as they going to be very closely looked at.
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I don't have to grasp at any straws at all.
Most folk don't know they have an induction leak. Where is your data on that. For once that is not a DATA POINT i have collected but it is anecdotal and accurateThat's another I pull that out of the blue sky. What a crock. Induction leak is the quickest thing you will know about may take some time to find where it is. No it is not, massive leaks yes, but I really do wonder how many engines you really have first hand diagnosis experience on when you make comments like that. Most leaks (by number) are not the massive ones that are dead easy to feel and easy to find. However, the majority are for the non LOP and data analysis nerds insidious and sneak up slowly over time, and without an EMS and knowing what it is showing you, will go undetected for ages, and even years, even after an annual inspection. There is one in my hangar right now, recently back from one of the better maintenance shops around. They simply could not explain the pilots question other than its a carby distribution thing.
Jaba
For the record exactly what aviation qualifications do you have.
For the record exactly what aviation qualifications do you have.
But just like asking who knows more about the design of a B747, the engineers who designed it or the lady screwing the Hyloc's in the aft section of the fuse? And yes I know that answer to that one in more detail than you can imagine 
The point is I'm making is that people like to have a dig yet they don't have the qualifications to have it.
I think if we divided Andy RR's qualifications by mine numerically we would still have a numbers exceeding yours…..but really in the end that is just a pi$$ing contest and means little. So quit while you are not so far behind on that, and we might drop it too.
But what I've been told is true after the acciedent in Melbroune this week some things may be up for change as they going to be very closely looked at.
If it were democratised, like the auto industry, it would be able to generate the sales and use volumes that would bring prices down.
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We'll I can say a whole lot more dyicnoics than you Jaba. I've had to remove 5 engines in the last 3 months for various reasons. And I can tell you an induction leak really is not common and when you do have one it's quite simple to know what it is.
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And I can tell you an induction leak really is not common
it's quite simple to know what it is.
19th Oct 2014 16:34
19th Oct 2014 16:34
But let me say this, regardless of what you think you know about intake leaks (the easy ones) the Turbo diesel ones will be REALLY easy to detect
So, please tell us all how and what tools you would use to find an intake leak (that is very easy for me to detect), that offers no rough running and no visible stains or anything visible to the naked eye. And it still ran fine LOP, which normally is one give away, and started and ran at idle quite happily too.
I am genuinely keen to learn (no doubt others also), as I am prepared to admit I do not claim to know everything and there is always a chance I could learn from you on this topic apparently.
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We'll Jaba you proclaim to be the super hero here you quite often told me how my training is inadequate and my text books are all wrong.
You still not told us all what aviation qualifications you have or how many days this year you spent in a maintenance shop.
You still not told us all what aviation qualifications you have or how many days this year you spent in a maintenance shop.