PC-12 vs. Turbo Commander
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Hi :-)
I think the eternal discussion about Twin versus Single is just going into the next lap...
Twin vs Single is - IMHO - a quiet personal question: I prefer not having to swith to "glider mode" in an instance, especially whilst near the mud. Someone else might fear the asymmetry more than "gliding into the night". For each one his own...
Question: Is a turbine running on its design goal, thermodynamically speaking, more prone to failures than a de-rated, larger turbine? I do remember reading a tech article about the de-rated turbines being more prone to carbon residues etc. - literally negating the benefits of lesser thermal strain...?!
Btw, I would never try to fly from Seattle to Miami NONSTOP in a PROP *shudder* :-)
Kind regards,
Peter
I think the eternal discussion about Twin versus Single is just going into the next lap...
Twin vs Single is - IMHO - a quiet personal question: I prefer not having to swith to "glider mode" in an instance, especially whilst near the mud. Someone else might fear the asymmetry more than "gliding into the night". For each one his own...
Question: Is a turbine running on its design goal, thermodynamically speaking, more prone to failures than a de-rated, larger turbine? I do remember reading a tech article about the de-rated turbines being more prone to carbon residues etc. - literally negating the benefits of lesser thermal strain...?!
Btw, I would never try to fly from Seattle to Miami NONSTOP in a PROP *shudder* :-)
Kind regards,
Peter
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DBW
You obviosly know your PC-12, and this debate has been done before.
But a couple of points you make I can't agree on. If you could expand on them it may be helpful.
Can you back this up. I have never seen this published. I've seen claims alluding to this but per flying hour etc etc is it better than caravans, TBM's or even a Bonanza?
Disagree entirely. If one has an engine failure in a turbine twin I wouldn't consider it an emergency. I am not landing now. I will continue my climb at 600fpm or so minimum, get to msa, consider my options and then make an approach somewhere and land on the runway where there are emergency services on hand. Contrast that to any single, 300' ceiling, engine fails just as you pass over the end of the runway on departure. What are you going to do. Or indeed anytime. You are going down.
Rubbish, I'd like to see the evidence of this!!
Google pc-12 engine failure. More than two.
You mention more than double the fuel consumption. Again I disagree. I flew a 200GT this morning at FL290, TAS 292 burning 600lb/hr.
You clearly know the PC-12. Can you confirm the inspection interval is 100hrs? Surely this is a major negative compared with a machine at 200hrs.
What effect does runway contaminant or icing conditions have on your performance? I have seen the numbers, not very good.
As I said before I think they are great machines, but the original post asked about safety. There is no competition for the twin on this criteria. And I get frustrated reading comments such as there have only been two engine failures on PC-12s. There have been many more. I hope they sell many more airplanes but only to informed customers, not people who are being told they have no worries about engine failures as they don't fail and if they do they'll reach a field but they are no safer than twins anyway as both are going down regardless.
You obviosly know your PC-12, and this debate has been done before.
But a couple of points you make I can't agree on. If you could expand on them it may be helpful.
The PC-12 has a far lower probability of failure than any single engine made
And engine failure in a twin is everybit the emergency in a single, you are landing...now.
A twin (fact) has 4 times the risk of engine failure than a single engine PC-12...
when I last checked there have been 2 documented failures, both were low time aircraft.
You mention more than double the fuel consumption. Again I disagree. I flew a 200GT this morning at FL290, TAS 292 burning 600lb/hr.
You clearly know the PC-12. Can you confirm the inspection interval is 100hrs? Surely this is a major negative compared with a machine at 200hrs.
What effect does runway contaminant or icing conditions have on your performance? I have seen the numbers, not very good.
As I said before I think they are great machines, but the original post asked about safety. There is no competition for the twin on this criteria. And I get frustrated reading comments such as there have only been two engine failures on PC-12s. There have been many more. I hope they sell many more airplanes but only to informed customers, not people who are being told they have no worries about engine failures as they don't fail and if they do they'll reach a field but they are no safer than twins anyway as both are going down regardless.
I also understand that the RCMP had a engine failure out of YZF, they turned around and landed safely on the reciprocal runway. No accident ergo no paperwork. Can any CDN PPruner's confirm or deny
Safety first
I would say how the plane is operated has to be taken into account.
There is a difference between a two man crew full time professional crew versus a lower time single pilot owner operator situation.
Another factor is age of the airplane. You are more likely to have problems in an older, more complex plane. Who is managing the MX is also a legitimate factor. An out of the box PC-12 under factory support is going to be less work that an older twin. Who is going to be doing that work?
If it is single pilot owner operated I'd be inclined to go for a new PC-12.
Nice problem to have either way.
20driver
There is a difference between a two man crew full time professional crew versus a lower time single pilot owner operator situation.
Another factor is age of the airplane. You are more likely to have problems in an older, more complex plane. Who is managing the MX is also a legitimate factor. An out of the box PC-12 under factory support is going to be less work that an older twin. Who is going to be doing that work?
If it is single pilot owner operated I'd be inclined to go for a new PC-12.
Nice problem to have either way.
20driver
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A Twin turbine has to use the smallest engine possible running at the highest power close to its maximum thermo dynamic rating in order to offset the inefficiency of having TWO engines.
A twin turbine most certainly doesn't have any need to use the smallest engine possible. Neither is there any need nor requirement to run at "maximum thermodynamic rating," and neither is there an inefficiency associated with two engines.
I gather you have little or no multi engine time, and certainly no turbine multi-engine experience. Is this so?
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Are you asking a question that you can answer?
I don't fly the PC-12. If you have a point to make, then make it.
When you ask about a thermodynamic rating, are you referring to the maximum ITT, or are you referring to the maximum torque/horsepower output at maximum ITT at that altitude, under a given set of environmental conditions?
I don't fly the PC-12. If you have a point to make, then make it.
When you ask about a thermodynamic rating, are you referring to the maximum ITT, or are you referring to the maximum torque/horsepower output at maximum ITT at that altitude, under a given set of environmental conditions?
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These debates are usually fought by those that don't fly over water, in the clouds, over mountains, or in places where an un-powered landing means certain death.
Only an idiot pays $3 mil for a single engine aircraft, thinking that some how years later, after 5000 hours of hoping that he doesn't have to ditch his aircraft...NOW he can reap the benefits of only having to pay for one engine to overhaul.
Reminds of doctors buying a $450,000 Bonanza, when a $150,000 Cessna 340 would have been a much better choice, but hey, they thought it was a good idea to not have to spend a week, and $1000 working on a twin rating.
This argument would be mute if everyone in here had to take off from Bagdad to Kandahar, knowing that ditching at anytime meant you would get your head cut off on the internet. Amazing how all the statistics would go right out the window.
Carry on.
Only an idiot pays $3 mil for a single engine aircraft, thinking that some how years later, after 5000 hours of hoping that he doesn't have to ditch his aircraft...NOW he can reap the benefits of only having to pay for one engine to overhaul.
Reminds of doctors buying a $450,000 Bonanza, when a $150,000 Cessna 340 would have been a much better choice, but hey, they thought it was a good idea to not have to spend a week, and $1000 working on a twin rating.
This argument would be mute if everyone in here had to take off from Bagdad to Kandahar, knowing that ditching at anytime meant you would get your head cut off on the internet. Amazing how all the statistics would go right out the window.
Carry on.
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I don't know about that. I've got plenty of time flying in very hostile terrain in single engine and multi engine airplanes, including flying both at low level in active wildfires in very cut-up terrain, as well as flying in places where lots of people are shooting.
My interest here are the false claims made thus far. Certainly if one wishes to fly single engine in the mountains or over the sea, so be it.
Afghanistan is another animal. Contractual requirements, as well as performance requirements dictate that most operations are multi engine.
There are operations conducted there using PC-12's, however, as well as Cessna 208's.
My interest here are the false claims made thus far. Certainly if one wishes to fly single engine in the mountains or over the sea, so be it.
Afghanistan is another animal. Contractual requirements, as well as performance requirements dictate that most operations are multi engine.
There are operations conducted there using PC-12's, however, as well as Cessna 208's.
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Twin or Single?
Not sure about the pc-12 or the twin commander. But I love the twin commander. Though just flew as a passenger.
I fly singles over the mountains(the highest ones in the world). It sure does lack the performance and they is always a thing in the mind. An engine failure can occur anytime. And its rare that you have a flat field around to land (one would need atleast 1500 ft of flat land, that is like 3 lenths of football field, that is rare to find). So I wished I were flying a twin and not worry about the only engine I have.
I guess multi engine aircrafts were build for the fact they could carry more and provide additional safety.
For 3 million, you can get a DO-328.
I fly singles over the mountains(the highest ones in the world). It sure does lack the performance and they is always a thing in the mind. An engine failure can occur anytime. And its rare that you have a flat field around to land (one would need atleast 1500 ft of flat land, that is like 3 lenths of football field, that is rare to find). So I wished I were flying a twin and not worry about the only engine I have.
I guess multi engine aircrafts were build for the fact they could carry more and provide additional safety.
For 3 million, you can get a DO-328.
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These debates are usually fought by those that don't fly over water, in the clouds, over mountains, or in places where an un-powered landing means certain death.
Only an idiot pays $3 mil for a single engine aircraft, thinking that some how years later, after 5000 hours of hoping that he doesn't have to ditch his aircraft...NOW he can reap the benefits of only having to pay for one engine to overhaul.
...
Carry on.
Only an idiot pays $3 mil for a single engine aircraft, thinking that some how years later, after 5000 hours of hoping that he doesn't have to ditch his aircraft...NOW he can reap the benefits of only having to pay for one engine to overhaul.
...
Carry on.
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Fickle,
Not sure about that. The US Air Force operates approximately 20 PC12's in multiple roles. Some of the missions are in some very inhospitable places. I have a bit over 1,000 hours in a Pilatus, and while I'm not going to get into the multi-single argument, I can say that the PC12 is built stout.
Not sure about that. The US Air Force operates approximately 20 PC12's in multiple roles. Some of the missions are in some very inhospitable places. I have a bit over 1,000 hours in a Pilatus, and while I'm not going to get into the multi-single argument, I can say that the PC12 is built stout.
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This argument would be mute if everyone in here had to take off from Bagdad to Kandahar, knowing that ditching at anytime meant you would get your head cut off on the internet.
You did say that the conversation would draw quickly to a close if others were forced to make that trip or fly from those locations. I've certainly done it, and don't agree; have you?
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IŽd guess all pro and contra single vs.multiengine had been exchanged.
I also guess that an individual wealthy enough to have to make such a choice is probably intelligent enough to understand them.
Could you please remind me, whats the point in continuing?
I also guess that an individual wealthy enough to have to make such a choice is probably intelligent enough to understand them.
Could you please remind me, whats the point in continuing?
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There is no debate. Those that have flown planes long enough, have probably been around to have seen a few engines go out on them....but don't take my word for it....
When a PC12 went down in the Sea of Japan, I am pretty sure everyone on board was very happy to only have had one engine, confident that the ditching to ensue really wasn't that big of a deal. And as they sat there in the life rafts freezing to death waiting for the SAR aircraft arrive, they all felt confident that single engine ops were really a great thing.
I wonder if Sully would have liked to have a few more engines before going into the Hudson? Nah....
When a PC12 went down in the Sea of Japan, I am pretty sure everyone on board was very happy to only have had one engine, confident that the ditching to ensue really wasn't that big of a deal. And as they sat there in the life rafts freezing to death waiting for the SAR aircraft arrive, they all felt confident that single engine ops were really a great thing.
I wonder if Sully would have liked to have a few more engines before going into the Hudson? Nah....
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The debate rumbles on. If cost/money was not an issue, would we not all prefer/fly multi's?
If a PIC of a twin had an engine failure taxying to take off, he would not take off. Yet millions take off with a single engine, single generator.....
Asked my wife if money no object would she prefer a G550 or 7x - the 7x. Passengers like more engines - but then when has a passengers needs come before profits.
If a PIC of a twin had an engine failure taxying to take off, he would not take off. Yet millions take off with a single engine, single generator.....
Asked my wife if money no object would she prefer a G550 or 7x - the 7x. Passengers like more engines - but then when has a passengers needs come before profits.
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If a PIC of a twin had an engine failure taxying to take off, he would not take off. Yet millions take off with a single engine, single generator.....
You really can't compare a twin engine airplane attempting to takeoff with assymetrical thrust and an engine failed, to departing in a fully functioning single engine airplane with one generator.
Did you think this out before you made the argument?
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(When a PC12 went down in the Sea of Japan, I am pretty sure everyone on board was very happy to only have had one engine, confident that the ditching to ensue really wasn't that big of a deal. And as they sat there in the life rafts freezing to death waiting for the SAR aircraft arrive, they all felt confident that single engine ops were really a great thing.)
Nonsense! In a Turbo Commander, the same scenario after an engine failure and feathering the prop in the affected engine the twin will KEEP FLYING at 200 KTAS instead of gliding. thus making it to destination or diverting to a safe landing in another airport. Simple as that.
By the way, in that accident SAR they were never dispatched, they were picked up by a cargo ship. And If a Russian SAR helicopter was going to do the rescue would have been a TWIN engined Mi-8.
Nonsense! In a Turbo Commander, the same scenario after an engine failure and feathering the prop in the affected engine the twin will KEEP FLYING at 200 KTAS instead of gliding. thus making it to destination or diverting to a safe landing in another airport. Simple as that.
By the way, in that accident SAR they were never dispatched, they were picked up by a cargo ship. And If a Russian SAR helicopter was going to do the rescue would have been a TWIN engined Mi-8.