Twin piston or single turboprop?

Insane

Insane

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Insane
So which one would you prefer? Piston engines are notoriously unreliable and unfortunately light piston twins are unsafe when one of their old junky piston engines quit. On the other side of the coin flying over the ocean or at night with only one old junky piston engine sounds even more scary.

So what is the next best option? A single turboprop? I think I'd prefer to be in a jetprop bonanza rather than a light piston twin flying in the mountains at night.

Opinions?
 
I think Progressive's claim that you can get the cheapest car insurance is overstated.
 
Which one is free?
Either would be fine with me
 
Lot's of opinions, and all contain the words, "it depends". :D
Depends on: the mission, the purchase price, the operating budget, the pilot's experience, the distance/passenger load, and how cool the pilot wants to look at cocktail parties. :D
 
Which one is going to win in a race to final?
 
A hanger mate of mine had one of those "jetprop Bonanzas". The last annual involved a $100,000 hot section teardown. And on the first flight after the rebuild, the engine lost power and he had to set it down in a corn field.

I'll stick with my Rotax 912.
 
OUCH:mad2: :eek:
Old Geek said:
A hanger mate of mine had one of those "jetprop Bonanzas". The last annual involved a $100,000 hot section teardown. And on the first flight after the rebuild, the engine lost power and he had to set it down in a corn field.

I'll stick with my Rotax 912.
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Over tall rocks day or night? Neither.

Over water? The junky piston twin.

If I didn't have dependents? A piper arrow for all the above. :D
 
Hmm, was that a PT6 or some other turbine?
 
PT-6 engine reliability is grossly overstated.

I'll take a well maintained piston twin any day.
 
dans2992 said:
Hmm, was that a PT6 or some other turbine?
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I think they are Allison or Rolls Royce, but $100K for a hot section seems pretty high, but a lot of very expensive parts can get trashed with improper operation. :eek:
 
knock on wood, I've had pretty good outcomes as I inch into 1000 hours voluntarily gambling with my life sitting behind a pedestrian who in turn is sitting in front of a -68 variant. Of course, it's uncle sam throwing gobs of money at it and R2ing engines like they're Lego pieces. I can't speak for the single owner/operator maintenance reliability. I would assume that'd be lower.

When pax are concerned, I'd still be inclined to fly a piston twin overwater, over a single of any kind.
 
Neither. I use the sun. Starpower is the only way to fly.
 
Insane said:
So which one would you prefer? Piston engines are notoriously unreliable and unfortunately light piston twins are unsafe when one of their old junky piston engines quit. On the other side of the coin flying over the ocean or at night with only one old junky piston engine sounds even more scary.
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enu7ygeg.jpg
 
B-52, so when the excrement hit the fan I will have to do the dreaded seven engine approach. :yes:
 
Insane said:
So which one would you prefer? Piston engines are notoriously unreliable and unfortunately light piston twins are unsafe when one of their old junky piston engines quit. On the other side of the coin flying over the ocean or at night with only one old junky piston engine sounds even more scary.

So what is the next best option? A single turboprop? I think I'd prefer to be in a jetprop bonanza rather than a light piston twin flying in the mountains at night.

Opinions?
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Depends on how far you want to go. Very short trips, a jet prop Bonanza is nice, but the problem with all the turbine conversions is the fuel specifics combined with their horsepower ratings end up leaving you with a short legged bird unless you add significant fuel tankage.

Turbines without pressurization are seriously handicapping the engine to operating outside its zone of peak efficiency. If I was going turbine single TBM, Meridian, or PC-12 for larger capacity w/ lav option, is where I would be looking.

Reality is the piston engines we operate are very reliable when correctly maintained and operated, they are designed to keep running with a lot of stuff wrong.
 
Henning said:
Reality is the piston engines we operate are very reliable when correctly maintained and operated, they are designed to keep running with a lot of stuff wrong.
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If you had to guess, how much greater would you say the odds of a failure on a piston engine are than a turbine engine?
 
It is impossible to guess the odds, since nobody is counting the times a twin turbine comes in with a dead engine. Remember the VAST majority of PT-6s are on King Airs, and a failure of one is almost a non event.
 
Insane said:
So which one would you prefer?
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I would prefer a single turboprop over a twin piston but I don't agree with a sweeping statement that piston engines are 'notoriously' unreliable. I like smoothness and power behind the turboprops plus I might not trust a pilot (or myself if I am the pilot) to handle an engine failure on a twin piston.
 
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kgruber said:
It is impossible to guess the odds, since nobody is counting the times a twin turbine comes in with a dead engine. Remember the VAST majority of PT-6s are on King Airs, and a failure of one is almost a non event.
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Well, it's impossible to _know_ the odds, but it's always possible to guess at them.

;)
 
Flown piston and turbines, had a few failures, turbine (even single) is just more reliable IMO
 
Henning said:
If I was going turbine single TBM, Meridian, or PC-12 for larger capacity w/ lav option, is where I would be looking.
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I like the new interior on the TBM 900. Multiple quick configuration options. That's nice flexibility in an airframe that size.
 
Richard Collins once observed that statistical probability of failures and fatal outcomes is such that you are better off flying a King Air without a multi rating than flying any kind of piston twin with such. Let it sink for a moment.

Basically what it comes to, people crash twins a lot and their stats are awful. Why is a different matter. Can you beat the stats? Possibly. Have to know the hardware better than your mechanic and sit in simulator every month, and voila.

Turbines undoubtedly fail. I remember one old case when a guy ditched a PC-12 off Kamchatka. Those seas are so cold that you have consciousiness time of something like 1 minute. He managed to climb into a raft and was rescued, but man. What an adventure. That PT-6 just quit in flight with no warning.

Even so I would rather fly behind a PT-6. I just don't trust my training enough and I'm too busy with stuff.
 
zaitcev said:
Richard Collins once observed that statistical probability of failures and fatal outcomes is such that you are better off flying a King Air without a multi rating than flying any kind of piston twin with such. Let it sink for a moment.



Basically what it comes to, people crash twins a lot and their stats are awful. Why is a different matter. Can you beat the stats? Possibly. Have to know the hardware better than your mechanic and sit in simulator every month, and voila.
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I actually like and respect Richard Collins, but what he wrote about twins vs singles is rather dated. ME training has improved greatly over the last few decades. While recent stats aren't necessarily great, they are not as dismal as when Collins was examining the twin vs single debate.
 
I'd take the twin. Lower acquisition cost. Fuel burn comparable or less. Overall maintenance likely less.

As mentioned, a turboprop only makes sense with pressurization so you can fly it where they want to be flown. I'd take a turbo normalized Bo over a jetprop conversion. More bang for the buck.
 
LDJones said:
I'd take the twin. Lower acquisition cost. Fuel burn comparable or less. Overall maintenance likely less.
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I agree with your logic but applying the same logic to a twin, it is better to take a single piston. Because it would have "Lower acquisition cost. Fuel burn comparable or less. Overall maintenance likely less"
 
Biggest differences in piston and turbine maintenance are: turbines are more reliable, require less unscheduled maintenance and produce more hp for a given weight. Pistons are cheaper to buy and operate in most cases, easier to get serviced, simple repairs compared to turbines, generally less systems on a piston airplane vs a turbine.
The real difference is the cost of the surprises! A piston engine surprise is $500-2000.00 a turbine surprise can be $2500-50,000.00 :mad2::mad2:
 
LDJones said:
As mentioned, a turboprop only makes sense with pressurization so you can fly it where they want to be flown. I'd take a turbo normalized Bo over a jetprop conversion. More bang for the buck.
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Yep. For an unpressurized airplane, you pretty much want to be going about 20nm for each 1000 feet you're going to climb. If you're only going 300nm, it doesn't make sense to go above 15,000 and you won't get the full speed advantage of either a turboprop or a turbo piston.
 
Insane said:
I agree with your logic but applying the same logic to a twin, it is better to take a single piston. Because it would have "Lower acquisition cost. Fuel burn comparable or less. Overall maintenance likely less"
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But the point of the exercise was improving safety/reliability over piston single.
 
flyingcheesehead said:
Yep. For an unpressurized airplane, you pretty much want to be going about 20nm for each 1000 feet you're going to climb. If you're only going 300nm, it doesn't make sense to go above 15,000 and you won't get the full speed advantage of either a turboprop or a turbo piston.
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True, but the turboprop is going to be burning fuel at a higher rate at 10,000 ft than it will at 20,000 ft. The turbo piston has essentially the same GPH at 3000 and 20,000 ft.;) Speeds of course increase with altitude, turbo props need to fly above 15,000 ft to be economical........OK economical isn't a good word in that sentence. ;)
For example I flew my 421 from FTY to AHN, 60 nm, 5-6,000 ft, TAS 180-185 knots@ 42 GPH, same trip in Conquest same altitudes, TAS 200-210, 80 GPH! :eek:
Longer trips 421 still burns 42 GPH, at 16,000 ft I would get 195-200 knots, the Conquest at 20,000 ft burns 70 GPH and trues at 255-260. The 421 still burns more fuel for the trip, but the gap is closer as the altitude increases. For my money, turbines need pressurization to make them practical traveling machines. ;)
 
Insane said:
I agree with your logic but applying the same logic to a twin, it is better to take a single piston. Because it would have "Lower acquisition cost. Fuel burn comparable or less. Overall maintenance likely less"
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HP Single lower acquisition cost than comparable twin? On what planet?
 
Henning said:
HP Single lower acquisition cost than comparable twin? On what planet?
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Go back and look at what I wrote and tell me what extra word you inserted then tell me the ramifications of that. ;)
 
Insane said:
Go back and look at what I wrote and tell me what extra word you inserted then tell me the ramifications of that. ;)
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If we're going to compare airplanes, we do need to at least make them a little bit similar. A 150 is cheaper to buy and operate than a Baron, you win!:mad2:
A better comparison is a Baron 58 and an A-36 Bonanza for piston single vs twin. Hard to compare simple single pistons to all sizes of piston twins to turbine singles, both factory and conversions. :dunno:
 
N747JB said:
True, but the turboprop is going to be burning fuel at a higher rate at 10,000 ft than it will at 20,000 ft. The turbo piston has essentially the same GPH at 3000 and 20,000 ft.;) Speeds of course increase with altitude, turbo props need to fly above 15,000 ft to be economical........
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Yup - But that's exactly why they need to be pressurized. When they're pressurized it's OK to climb and descend at thousands of feet per minute (if capable). Unpressurized, that's not OK ever.

OK economical isn't a good word in that sentence. ;)
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:rofl: True! Maybe the insertion of "relatively" before it would have helped. ;)

For example I flew my 421 from FTY to AHN, 60 nm, 5-6,000 ft, TAS 180-185 knots@ 42 GPH, same trip in Conquest same altitudes, TAS 200-210, 80 GPH! :eek:
Longer trips 421 still burns 42 GPH, at 16,000 ft I would get 195-200 knots, the Conquest at 20,000 ft burns 70 GPH and trues at 255-260. The 421 still burns more fuel for the trip, but the gap is closer as the altitude increases. For my money, turbines need pressurization to make them practical traveling machines. ;)
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Yep, that's exactly the point Loren was trying to make, and I was trying to emphasize. A turbine Bonanza is a waste of a good airplane, just to say you've got a turbine engine and can burn fuel faster than your Bo brethren (with decreased range etc etc).

Turbines are worthless unless you're either pressurized or have a specific need for the kind of excess power they can provide.

Turbos on a piston engine are only really worthwhile if the majority of your flights are in the hundreds of nautical miles or you regularly need to fly IFR over the Rockies. There have been times where I wished the Mooney had turbos on it, but I make frequent enough $100 burger flights and short <100nm hops over to see my parents that it'd kind of be a waste for the couple of times I really could have used them.
 
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