Supercharging

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LJS1993

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LJ Savala
Hey guys first off let me say if I am way off on this forgive me. However I have noticed a lot of turbo's in aviation but no supercharging. I know turbos have a lot of lag so why not use supercharging in aviation?
 
Weight, heat and crankshaft load to name a few.

Lag is irrelevant in fixed power applications.
 
LJS1993 said:
Hey guys first off let me say if I am way off on this forgive me. However I have noticed a lot of turbo's in aviation but no supercharging. I know turbos have a lot of lag so why not use supercharging in aviation?
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Simple, lag doesn't matter to us as we run fairly constant power and a second or two for MP to spool up is fine and predictable plus it is more energy economical as it is being driven by the 75% btu value of the fuel that would be thrown away out the exhaust rather than the 30hp that could be going to the prop. Get it? Turbocharging is the more elegant and efficient system.

Now, if you want to talk about stacking systems, we can do that too.:yesnod: for when two turbo's just ain't enough air...:rofl:
 
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LJS1993 said:
Hey guys first off let me say if I am way off on this forgive me. However I have noticed a lot of turbo's in aviation but no supercharging. I know turbos have a lot of lag so why not use supercharging in aviation?
Click to expand...

Many engines in Aviation have supercharging, and some have power recovery turbines (PRTs) too.
 
Also, just a a phraseology note, "supercharging" refers to boosting manifold pressure above sea level atmospheric. You can have a turbo-normalized engine, which just compensates for altitude, or a turbo-supercharged engine (eg TSIO 360) which boosts well above 32 inches to deliver full power.
 
Tom-D said:
Many engines in Aviation have supercharging, and some have power recovery turbines (PRTs) too.
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It's worth noting that none of them have been produced or supported since before Reagan was in office. In many cases, as far back as when he was an actor.

As has been said, turbos are more efficient than superchargers, and ultimately proved more reliable. Power recovery turbines proved to be pretty unreliable, as well.
 
As has been said, turbos are more efficient than superchargers, and ultimately proved more reliable. Power recovery turbines proved to be pretty unreliable, as well.
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PRT's weren't unreliable. Superchargers were quite efficient, and standard on most large radials. Most large radials, in fact were both turbocharged and supercharged, with the most advanced of them being the R-3350, which was turbo supercharged with power turbine recovery.
 
DouglasBader said:
PRT's weren't unreliable. Superchargers were quite efficient, and standard on most large radials. Most large radials, in fact were both turbocharged and supercharged, with the most advanced of them being the R-3350, which was turbo supercharged with power turbine recovery.
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And ultimately they were so great that everyone switched to turbines.

Turbos are more efficient than superchargers by a good margin. If you don't believe it, look at some engine specs and BSFC at rated power. IGSO-540 is the worst BSFC I've ever seen for a piston engine at rated by about 15%.
 
Ted DuPuis said:
And ultimately they were so great that everyone switched to turbines.

Turbos are more efficient than superchargers by a good margin. If you don't believe it, look at some engine specs and BSFC at rated power. IGSO-540 is the worst BSFC I've ever seen for a piston engine at rated by about 15%.
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"efficient" isn't what I'd call a small turbine,
 
Tom-D said:
"efficient" isn't what I'd call a small turbine,
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I'd agree. However, operating costs have to do with more than simply fuel burn. It's also reliability and maintenance costs. And, well, turbines have won that battle for the planes on the order of what used to have R-3350s.
 
kyleb said:
Which is why nobody made that claim...
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Post #6

"
As has been said, turbos are more efficient than superchargers, and ultimately proved more reliable. Power recovery turbines proved to be pretty unreliable, as well."

That's what prompted my statement.
 
Exhaust turbocharging is a lot easier to do than re-designing the engine case to add add a supercharger, the TSIO evolved from the non "T" engines in most cases.
 
Tom-D said:
Post #6

"
As has been said, turbos are more efficient than superchargers, and ultimately proved more reliable. Power recovery turbines proved to be pretty unreliable, as well."

That's what prompted my statement.
Click to expand...

Turbos is turbo chargers, not turbines, although it is lol.
 
Ted DuPuis said:
TIO-540 is more efficient than IGSO-540 by a good margin.
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And as I have said they are still out there, quoted from the Lycoming Flyer

"A supercharged, geared, opposed, fuel-injected Lycoming engine with cylinders of 540-cubic inch displacement is desig- nated an IGSO-540 model. “S” represents supercharging."

Good bad or in deferent, I made no statement to that.

I simply said
"Many engines in Aviation have supercharging, and some have power recovery turbines (PRTs) too."

and like always, this board took a turn to thread creep.
 
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Tom-D said:
Exhaust turbocharging is a lot easier to do than re-designing the engine case to add add a supercharger, the TSIO evolved from the non "T" engines in most cases.
Click to expand...
You can bolt on superchargers as well and shaft, gear or belt drive them. the 20-645-E7 EMD had an interesting spur and dog hybrid that had a through shaft that attached to a spur gear off the crank through a dog clutch. Since they were 2 strokes they could barely run without a supercharger; at idle and low RPM it acted as a gear driven centrifugal supercharger. As soon as enough pressure builds in the pipe it over runs the dog and functions as a turbo. Pretty slick, huge though and ungodly loud when putting out 3600hp*2.:eek:
 
Henning said:
Turbos is turbo chargers, not turbines, although it is lol.
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Do you know what a PRT is? what does the "T" stand for?

But as a point, the turbocharger is recovering lost power by converting the heat and velocity of the exhaust gases to power a compressor.
 
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There's a company that has an STC for an aftermarket supercharger for the Cirrus SR-22. I think it fits where the air conditioner would fit, if the plane had one, making it easy to add the belt drive and mount the compressor.

I suspect that fitting the plane with the supercharger might hurt the resale value, judging from what I've seen in the asking price in SR22 ads on Controller -- the handful of supercharged planes I've seen advertised are certainly not commanding a premium. Maybe buyers aren't sure what it's about, or worried that the engine might not last as long due to detonation or some other problem if it had the supercharger, and there's nobody to support the owner regarding the supercharger other than the little company that owns the STC, assuming they stay in business.
 
Tom-D said:
Do you know what a PRT is? what does the "T" stand for?

But as a point, the turbocharger is recovering lost power by converting the heat and velocity of the exhaust gases to power a compressor.
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Yeah I know what the hydrostatic PRT system on the 3350 is, I'm familiar, it's cool, it's another way to do it. With a 4360 you get to split it.;)
 
NoHeat said:
There's a company that has an STC for an aftermarket supercharger for the Cirrus SR-22. I think it fits where the air conditioner would fit, if the plane had one, making it easy to add the belt drive and mount the compressor.

I suspect that fitting the plane with the supercharger might hurt the resale value, judging from what I've seen in the asking price in SR22 ads on Controller -- the handful of supercharged planes I've seen advertised are certainly not commanding a premium. Maybe buyers aren't sure what it's about, or worried that the engine might not last as long due to detonation or some other problem if it had the supercharger, and there's nobody to support the owner regarding the supercharger other than the little company that owns the STC, assuming they stay in business.
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Also fits Cessna 182. DA40 in the works too.

Supercharges are great, don't get me wrong. I like the unit on my car. However when they replaced the blower with a little turbo the power went from 205 to 260
 
And ultimately they were so great that everyone switched to turbines.
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Which is a ridiculous statement.

One could say the same thing about the gnome rotary being eventually overshadowed by bigger and better.

The R3350 was the most advanced radial in it's time, and the PRT in combination with the turbocharging and supercharging was the most advanced, efficient power available for an aircraft.

The P2V operated with both R3350's and turbojets on the wings; it had avgas-powered J34's. The J34's, however, burned far too much fuel; each consumed as much fuel independently as both R3350's combined, and didn't put out nearly the power. Fuel consumption tripled upon lighting them off; hence, they were used for takeoff, with hydraulic doors blocking the inlet in flight to reduce drag...where they became mostly dead weight.

Certainly turbine engines have advanced reliability and performance. We don't fly large radials high into the flight levels today; we fly turbines, and we generally fly turbofans, not turbojets. Technology takes us higher and faster, but I don't see many turbines being installed on piston airplanes these days. We're not going to see them replaced. Your'e not likely to see the O-320 replaced with a turbine motor any more than the 0-470, or even the TSIO-520. In a few rare cases, perhaps, but not many.

Yes, turbines replaced the R3350 and other radials, though they're still in use today, too. We even had an STC to replace the R3350's on the P2V with T-56A9 turboshaft engines. In the end it didn't happen, largely because the T-56's were harder to come by and a lot more expensive than the R3350's.

And, well, turbines have won that battle for the planes on the order of what used to have R-3350s.
Click to expand...

Not really.
 
DouglasBader said:
The R3350 was the most advanced radial in it's time, and the PRT in combination with the turbocharging and supercharging was the most advanced, efficient power available for an aircraft.
Click to expand...
The 3350 had a 2 speed 2 stage supercharger, and 3 PRTs (power recovery turbines) they were never turbocharged.

get the terms correct so every one will understand.

The 3 PRTs each collecting exhaust from 120 Degrees of the engine, positioned at 2-6-10 o'clock positions ran at 90,000-105,000 RPM and were directly coupled to the rear of the crankshaft assembly and recovered about 800 horse power. they did not produce and air pressure to the carb or intake system or act as a turbocharger to boost MAP.

we ran 65 inches of MAP for 5 minutes with ADI on full. torque meter usually read 3650 horses (+-)

and Ted was right...... we got about 400-600 hours out of a rebuild.
 
Henning said:
Simple, lag doesn't matter to us as we run fairly constant power and a second or two for MP to spool up is fine and predictable plus it is more energy economical as it is being driven by the 75% btu value of the fuel that would be thrown away out the exhaust rather than the 30hp that could be going to the prop. Get it? Turbocharging is the more elegant and efficient system.

Now, if you want to talk about stacking systems, we can do that too.:yesnod: for when two turbo's just ain't enough air...:rofl:
Click to expand...

Okay I get it. I need to quit looking at aircraft engines in the same was as auto applications. In auto apps I KNOW supercharging is much better then turbos unless you go twin turbos in imports.
 
DouglasBader said:
PRT's weren't unreliable. Superchargers were quite efficient, and standard on most large radials. Most large radials, in fact were both turbocharged and supercharged, with the most advanced of them being the R-3350, which was turbo supercharged with power turbine recovery.
Click to expand...

Nice!!! Those must have been some awesome sounding radials with some high HP numbers.
 
Any radial sounds nice. The R4360, however was a symphony. The R3350 is a smooth running engine when tuned and operating properly.

Can anyone name a plane that is supercharged?
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Almost any large airplane with a radial engine.
 
LJS1993 said:
Okay I get it. I need to quit looking at aircraft engines in the same was as auto applications. In auto apps I KNOW supercharging is much better then turbos unless you go twin turbos in imports.
Click to expand...

Use multiple small turbos in car apps. Materials science has come a fair ways to reducing lag and a squirt of N2O2 will do the same especially when oxidizing nitromethane.
 
LJS1993 said:
Okay I get it. I need to quit looking at aircraft engines in the same was as auto applications. In auto apps I KNOW supercharging is much better then turbos unless you go twin turbos in imports.
Click to expand...

You know wrong
 
King Air 90, A90, B90.................supercharged for cabin pressurization!
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Bleed air on a turbine engine isn't quite the same thing as supercharging on a piston engine.
 
DouglasBader said:
Bleed air on a turbine engine isn't quite the same thing as supercharging on a piston engine.
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Actually he was referring to the cabin being supercharged, ie above ambient, because the OP stated supercharged airplane rather than supercharged engines I believe.
 
Henning said:
Actually he was referring to the cabin being supercharged, ie above ambient, because the OP stated supercharged airplane rather than supercharged engines I believe.
Click to expand...

OK now we have gone from engine's that are supercharged, to cabin pressurization.

That's a stretch
 
DouglasBader said:
Which is a ridiculous statement.

One could say the same thing about the gnome rotary being eventually overshadowed by bigger and better.

The R3350 was the most advanced radial in it's time, and the PRT in combination with the turbocharging and supercharging was the most advanced, efficient power available for an aircraft.

The P2V operated with both R3350's and turbojets on the wings; it had avgas-powered J34's. The J34's, however, burned far too much fuel; each consumed as much fuel independently as both R3350's combined, and didn't put out nearly the power. Fuel consumption tripled upon lighting them off; hence, they were used for takeoff, with hydraulic doors blocking the inlet in flight to reduce drag...where they became mostly dead weight.

Certainly turbine engines have advanced reliability and performance. We don't fly large radials high into the flight levels today; we fly turbines, and we generally fly turbofans, not turbojets. Technology takes us higher and faster, but I don't see many turbines being installed on piston airplanes these days. We're not going to see them replaced. Your'e not likely to see the O-320 replaced with a turbine motor any more than the 0-470, or even the TSIO-520. In a few rare cases, perhaps, but not many.

Yes, turbines replaced the R3350 and other radials, though they're still in use today, too. We even had an STC to replace the R3350's on the P2V with T-56A9 turboshaft engines. In the end it didn't happen, largely because the T-56's were harder to come by and a lot more expensive than the R3350's.



Not really.
Click to expand...

I agree, the cacophony of sounds made by round engines makes my heart sing. But personally, I think the turbo-compound 3350s did more to advance the jet age than any previous engine. Yes, it was a technical marvel, 18 cylinders, 2-stage, 2 speed blowers, 3 power recovery turbines, fuel injection, anti-detonation injection, (water methonal) all added up to an extraordinary amount of moving parts per cowling. And because it made more horsepower (per cubic inch) than earlier engines (in some cases, up to 3,500hp)...and ran lean of peak, it was the engine of choice for manufacturers of eras long haul, high speed airliners.

However, it wasn't long before the turbo-compound engines developed a reputation for ventilating the cowling - what with all the moving parts and high power per cu.in. Which is why one almost never sees those kind of airplanes around anymore. DC-6s are still operating, but no DC-7s, no 1649 Connies, very few C-119s. There are airplanes still flying with R-3350s...just not turbo-compound 3350s. P2V, for example.
 
what engine, how did you tell?
 

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j1b3h0 said:
I agree, the cacophony of sounds made by round engines makes my heart sing. But personally, I think the turbo-compound 3350s did more to advance the jet age than any previous engine. Yes, it was a technical marvel, 18 cylinders, 2-stage superchargers, 3 power recovery turbines, fuel injection, anti-detonation injection, (water methonal) all added up to an extraordinary amount of moving parts per cowling. And because it made more horsepower (per cubic inch) than earlier engines (in some cases, up to 3,500hp)...and ran lean of peak, it was the engine of choice for manufacturers of eras long haul, high speed airliners.

However, it wasn't long before the turbo-compound engines developed a reputation for ventilating the cowling - what with all the moving parts and high power per cu.in. Which is why one almost never sees those kind of airplanes around anymore. DC-6s are still operating, but no DC-7s, no 1649 Connies, very few C-119s. There are airplanes still flying with R-3350s...just not turbo-compound 3350s. P2V, for example.
Click to expand...

FTFA.
 
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