Diesel V8 flys
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yr right - I for one, also love the KISS principle. Unfortunately for us dinosaurs, substantial amounts of electronics that control a wide range of engine control inputs are here to stay.
If it wasn't for modern electronics, engines would still be relying on very imprecise engine fuelling setups, imprecise and less reliable ignition systems, and an inability to adjust a wide range of other important combustion controllers.
The main problems with electronics come with the "cheapest arrangement we can purchase" mentality, and the lack of knowledge of actual operating conditions by engine designers which results in poor positioning of electronics, and less-than-ideal-design wiring connectors and wiring harnesses.
Electronic components often have a huge profit margin in their selling price that is designed to recoup design and research costs.
If competition via aftermarket manufacturers is introduced, prices rapidly fall to realistic levels.
Unfortunately, aviation is still full of the "captive customer" or "captive market" production principle, that ensures high costs for owners.
If it wasn't for modern electronics, engines would still be relying on very imprecise engine fuelling setups, imprecise and less reliable ignition systems, and an inability to adjust a wide range of other important combustion controllers.
The main problems with electronics come with the "cheapest arrangement we can purchase" mentality, and the lack of knowledge of actual operating conditions by engine designers which results in poor positioning of electronics, and less-than-ideal-design wiring connectors and wiring harnesses.
Electronic components often have a huge profit margin in their selling price that is designed to recoup design and research costs.
If competition via aftermarket manufacturers is introduced, prices rapidly fall to realistic levels.
Unfortunately, aviation is still full of the "captive customer" or "captive market" production principle, that ensures high costs for owners.
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Remember flat screens TVs that where upwards of 20k when it's first here now you can get them for $100. Now why is that. Mass production. Aviation isn't like that. It's a unequivocal low production where 500 aircraft is a great deal.
Now nothing in aviation is cheap. Nor dose it ever get cheaper. Litagation insurance is the main reason. Yet what is developed in aviation finds it's way to the greater public in other areas. Carbon fibre is a prime example.
I change a turbine disc just recently. At $2000 each turbine blade and 54 in a disc they use to be around $550 ea. that's over 100k just in blades.
Fadec fine but in GA I have to ask why. What happens when it stops. Now remember it breaks. Who has spares. Equipment to look after it. Who then pays for that. What happens if it stops in the middle of no where. I'm not against change but the cost is going to hurt. I've heard flying schools removing glass screens and going back to dials because they can't afford the cost of a break down at arond $25k a hit for a replacement. Won't hurt my pocket but may hurt yours.
Now nothing in aviation is cheap. Nor dose it ever get cheaper. Litagation insurance is the main reason. Yet what is developed in aviation finds it's way to the greater public in other areas. Carbon fibre is a prime example.
I change a turbine disc just recently. At $2000 each turbine blade and 54 in a disc they use to be around $550 ea. that's over 100k just in blades.
Fadec fine but in GA I have to ask why. What happens when it stops. Now remember it breaks. Who has spares. Equipment to look after it. Who then pays for that. What happens if it stops in the middle of no where. I'm not against change but the cost is going to hurt. I've heard flying schools removing glass screens and going back to dials because they can't afford the cost of a break down at arond $25k a hit for a replacement. Won't hurt my pocket but may hurt yours.
onetrack
A good simple carby setup is more efficient than a good EFI set up in a modern car. Only problem is the carby set up will go out of tune quicker. Manufacturers plump for the less efficient EFI as it helps guarantee them a known state of tune and therefore known level of emmissions. Electronics are not universally better. Yr right makes some very good points as well.
A good simple carby setup is more efficient than a good EFI set up in a modern car. Only problem is the carby set up will go out of tune quicker. Manufacturers plump for the less efficient EFI as it helps guarantee them a known state of tune and therefore known level of emmissions. Electronics are not universally better. Yr right makes some very good points as well.
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Yr right - you're right. The cost is going to hurt, and it'll hurt more if an integrated circuit board dies in the middle of nowhere.
However, it's the way of the future. AFAIK, general aviation is now the only place where we buy 1950s technology with 2010s dollars. No disrespect intended to that technology of course - it's rugged and durable. But cars, boats, trucks, racing cars, all have moved to fuel injection, electronic ignition, hi-tech fuel economy, replace-it-don't-fix-it.
It's getting harder to buy avgas too, although that's a different argument.
However, it's the way of the future. AFAIK, general aviation is now the only place where we buy 1950s technology with 2010s dollars. No disrespect intended to that technology of course - it's rugged and durable. But cars, boats, trucks, racing cars, all have moved to fuel injection, electronic ignition, hi-tech fuel economy, replace-it-don't-fix-it.
It's getting harder to buy avgas too, although that's a different argument.
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FADEC is used quite successfully on light turbine helicopters, operating in very remote locations.
The EPS Vision 350 engine has a bosch general aviation technology control system so backup shouldn't be an issue.
CI is the way to the future, as long as initial costs can be lowered.
The EPS Vision 350 engine has a bosch general aviation technology control system so backup shouldn't be an issue.
CI is the way to the future, as long as initial costs can be lowered.
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A carby has a better mixture of the fuel to the air. That's why a 500ci prostock car can run at over 200 mph and mid 6 sec runs. This is not new information just everyone thinks cause it the latest it must be the greatest
cheers
cheers
I have heard that about NASCAR engines from several engineers, but cant get my head around it. Obviously the NASCAR engines are built to perform well at a precise rpm and have a very narrow operating rpm range. Below 4000 rpm they buck like horses but come on song at 7500. The intakes, heads and valves are optimised for a specific rpm.
So why wouldn't fuel being squirted through an injector at 27,000 psi atomise even better than a simple pressure drop through the venturi of a carburettor?
So why wouldn't fuel being squirted through an injector at 27,000 psi atomise even better than a simple pressure drop through the venturi of a carburettor?
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Plus the carby engine has the added advantage of being immune to carburettor icing ! Makes you wonder why they ever mucked about with this new dangled fuel injection stuff in the first place
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Constant Mass Flow
A carby is very good at mixing fuel and air at the appropriate ratio when mass flow is constant, eg an aircraft engine at constant RPM. When you change the RPM constantly such as in a car in traffic the carby cant keep up and this is when fuel injection comes into its own.
I would be interested to see if petrol direct injection would improve combustion/atomisation/metering over a carby in an aircraft engine
I would be interested to see if petrol direct injection would improve combustion/atomisation/metering over a carby in an aircraft engine
yr right is spouting so much ignorant ****e here, I'm surprised that everyone didn't pick up on 27/09's subtle satirical post...
Yr right...now you're gilding the Lilly! You know full well the only reason that prostocker is running a carbie is because the rules tell them to!
I can tell you it used to take me half a morning and two runs for a plug chop to get my 250ci tripple SU powered XP hardtop to run into the 13s...with a little nitrous...any late model car will stay in tune months longer. Mine would change with the weather! My son's car will run tens any day of the week on a factory turbo and electronics with only a different wastegate and intercooler.
To quote a movie line..."His grandmother wouldn't be scared to ride in it" where my car ran a huge cam solid lifters and a 9inch that was more locked than it needed to...electronics are the go!
I can tell you it used to take me half a morning and two runs for a plug chop to get my 250ci tripple SU powered XP hardtop to run into the 13s...with a little nitrous...any late model car will stay in tune months longer. Mine would change with the weather! My son's car will run tens any day of the week on a factory turbo and electronics with only a different wastegate and intercooler.
To quote a movie line..."His grandmother wouldn't be scared to ride in it" where my car ran a huge cam solid lifters and a 9inch that was more locked than it needed to...electronics are the go!
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Bus driver having crewed on a pro stock car I know the rules. Yes that is true but then have a look at any other class and then look at what is achived with just 8 thoarts. Mid 6s at over 200 mph I think it's impressive then consider what initro cars where running with them times. A carby tune at the right end will produce more power than an injection in a N/A environment.
Cheers
Cheers
Yes, it is impressive what performance can be had out of a carbie that resembles four buckets tied together and over 500cubes of highly tuned induction system...enough to suck the air out of a 20ft container in a minute.
Okta, thanks for that. Pilots are so use to revs held static by the prop and having to watch manifold pressure where diesels fuel up the instant the load comes on...counterintuitive.
Okta, thanks for that. Pilots are so use to revs held static by the prop and having to watch manifold pressure where diesels fuel up the instant the load comes on...counterintuitive.
Quote:
A good simple carby setup is more efficient than a good EFI set up in a modern car.
Do you have a source for this?
A good simple carby setup is more efficient than a good EFI set up in a modern car.
Do you have a source for this?
Going back to aero-diesel engines, mechanical injection is simple and reliable, however it is common rail (electronic) injection which gives the real gains in performance, economy and engine longevity, as the forces in the engine can be controlled so much better.
Piezo injectors give even better control and can allow more power to be extracted from an engine, but are, or at least were recently, prone to unreliability.
With electronics on a diesel aero engine, you have a choice between mounting the electronics on the engine or engine mount and have them shake around with the engine, or mount them in the airframe and run the risk of the wires fatiguing with the relative movement to the engine.
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The reason for a carby preformance is it better atomises the fuel into the whole volume of intake air. It's down size is it harder to control than efi.
It the hymomics of the desiel that's the worry for me.
It the hymomics of the desiel that's the worry for me.
Most phased port injection systems are injecting on the back of a closed inlet valve - immediately after valve closing for sequential systems - so a large part of mixture preparation is by evaporation.
You worry about some strange and irrelevant stuff...