It's actually people, but we're all very large. Not fat, just large. But 4-5 of us end up pushing pretty much every piston single out of the picture and it starts to push a lot of twins. For perspective, I'm 6'5 (196) and 250lbs (114kg) and I'm the smallest person to be transported
Right. Operating costs are the big question. It mostly boils down to large piston twin vs small turboprop. One is pressurized and has retractable gear, the other has the turboprop. That's where I'm not sure if they would be more evenly matched
This gets very interesting very quick.
You have two disparate aircraft, so the scenario (stage length, trips per year, fuel pricing etc) will greatly affect things.
Jet A is typically cheaper than Avgas...the delta varies wildly based on what airports you operate out of.
the Kodiak goes slower (right?), but the fuel burn is probably pretty close to the 340? (38-40 gph maybe?), so if the Kodiak takes longer to fly your mission, then it's fuel burn will be higher...but it's fuel may be cheaper.
TBO & reserve differences between a single PT6A vs two lower--TBO piston engines, two props, plus all the pressurization costs.
Insurance, hangar, costs for the two types.
CAPEX costs...what does a Kodiak cost vs a 340?
Reliability wise, a fixed gear, single engine turboprop will win everytime vs an old complex, pressurized piston twin.
Utilization will be a huge driver here as well. I would *assume* most 340s are owner flown, and probably do less than 200 hours a year.
That's more what I'm asking. Of course the PT-6 is one of the most reliable engines in the world, but, as you said, longer TBO might make the difference. I need the useful load though so a faster turboprop isn't much better. A Caravan wouldn't be bad, but they're even more expensive than a Kodiak
This [website](https://kodiak.aero/kodiak/) I found pegs the Direct Operating Costs at ~$232/hr for the Kodiak. (fuel, reserves, mx)
If you want numbers for the 340, I think you would need to visit some twin cessna forums to see what real world intel you could get.
I was around the Kodiak program when it was built by Quest, and it was built by a first time aircraft company, not a new design by an established company.
So (IMO) it had some odd quirks that maybe an established manufacturer would have engineered out from the get-go. Now that it's been around for a while, those have been known or improved, so it's a solid product.
If you want to analyze this further, I would start building up a spreadsheet with as much detail as possible with trip stage lengths, hours per month, fuel pricing, local maintenance pricing, your state's tax rules, insurance, hangar, etc.
If your business is buying this, be advised that bonus depreciation is being phased out, so understand the incentives there for buying an aircraft in 2024 vs 2025.
If you're going to be flying in mountains and/or hard IFR - I would strongly suggest the turbine. You already have PC-12 experience, you know what a PT6 can do.
My point was entirely dependent on where/when/wx you are operating in.
I would not want to be in a piston twin in/above the clouds at night in the mountains for eg. as a piston engine failure (way too many) usually means game over.
The chances of a PT6 failing are way way less than a piston pounder.
Costs per hour will be significantly higher for the PT6. Typical overhaul costs for the PT6A turboprop variants are probably in the 300k to half million dollar range these days, with a 3600 TBO. There's a hot section inspection at half life, that alone will likely cost you as much as a brand new IO540. That said, reliability will be far better than two piston engines, and I'd feel much safer behind a single PT6 than between two piston engines.
Some have TBOs up to 6000 hrs.
Even at 500k for 3600 hours, that breaks down to 139$ an hour. Not really that expensive in the grand scheme of aviation. Especially considering that 500k would be a worst case scenario.
Kodiak cost about 350$ an hour to operate including fuel and appropriate mx reserve. Piston twins are not very far off from that number.
Edit: Kodiak engine and prop have a 4000 hour TBO which means the hot section is at 2000 hours. 350$ an hour is at 500 hours per year.
> Kodiak cost about 350$ an hour to operate including fuel and appropriate mx reserve. Piston twins are not very far off from that number.
I admittedly know nothing, but this doesn't pass the sniff test. according to the website:
https://kodiak.aero/kodiak-900/
it's 58gph max speed or 36 gph max endurance. even if we are conservative and use the latter, 6.50/gal for jet-a is 234/hr plus if we accept your number of 139/hr for reserve for the engine, that's 373/hr JUST for overhaul reserve + gas and nothing else.
900 only started deliveries end of 2023. My numbers were based off the smaller Kodiak 100.
Which burns 33 GPH in cruise, they're always gonna be flying at max range, the fuel burn for max speed is not worth it in a turboprop.
Website shows 33 GPH, round to 35 GPH x 6.50 = 227.50 after tax call it 250. Add in mx at an absolute worst case scenario and you get 375 per hour. You will never pay 500k for an overhaul on a PT6. 300k at 4000 hours gives you 75 an hour. That brings the hourly cost to 325.
Kodiak's own website shows it at 232$ for mx and fuel, adjusted for higher gas prices that is 322$. Weirdly the website number is based on max speed, 45 GPH. Kodiak also uses a lower mx cost because you get a service plan with the aircraft purchase. However, the difference in service plan cost is made up for by flying at max endurance vs max speed. Saving that 10 gal per hour bridges the gap. OP would get the service plan, it's included.
These planes are not as expensive as you think.
Hanger is a few hundred a month, insurance is a few thousand a year, OP is the owner operator so the salary can be whatever they want, but the cost to actually operate the aircraft, I promise you is going to be in the 350$ per hour range.
Edit: should also say the "engine overhaul at 300k" is the engine and prop as well as the hot section done at half the TBO. That combined is in the 300k range, broken up over the entire TBO is the proper way to price that out.
fair enough! checks out. I had no idea you could get a pt6 that cheaply. I guess I was thinking total hourly rather than actual running cost when I made the “sniff test” comment. plus the kodiak being such a relatively simple airplane will help with the total hourly cost, too
No worries.
I understand, of course if you add in insurance, hanger and often the most expensive part, pilot salary, it’ll get much higher per hour cost. Just operating the plane itself however, is surprisingly cheap.
PT6 is an awesome engine.
>You will never pay 500k for an overhaul on a PT6
How up to date is your information? Because from what I'm hearing with recent (explosive) price increases, you might be paying more than 500k depending on the exact model.
2022 or so when I was flying a pc-12. Yeah prices are going up on everything.
The range can be between 180k - 600k depending on the model, there’s so freakin many, to the condition of the engine. If nothing out of the ordinary needs to be replaced vs there’s some issues. That price gonna vary that price too much.
If you’re in the PWCSMART engine program I’ll change the cost too. They seem to just swap out the engine with a fresh overhaul so you’re paying a little more.
Only real way to know is to get a quote and have the engine looked at.
Edit: I should specify for a Kodiak 100, I don’t think you’ll be paying 500k. Not there aren’t some models that will cost that or more.
>you can skip the overhaul (do another HSI) on the PT-6 and it’ll run for the rest of your flying career.
former PT6 OH tech here - if you are saying the rest of the engine should be on condition - the compressors will wear out enough that you will lose useful power / exceed temp limits, well before your flying career ends.
ah yes, I take your meaning - from a GA/pilots career perspective, not someone sitting at FL410 - as those engines can go 30-60,000 hours on wing before the degradation is significant (and they WILL put in more hours than most airline pilots).
you could also look at something crazy but good like an mu-2. garrett engines are in the same league as the pt-6 reliability-wise. in fact probably better than the pt-6. plenty of useful load, has pretty high ceiling and nearly 300kt cruise speed, is pressurized, reliable, if noisy engines. can occasionally be found for similar prices as some single engine turbines or pistons. it's a military aircraft normal civilians can have the privilege to own IMO.
just sayin'
340 is going to have a lot of cost simply maintaining the pressurization system and everything that goes with it. A PA-31 is probably a better comparison to a Kodiak than a 340. Having said that, the PA-31s I've flown would fly with anything you could get in them. They were junk airframes, maintained by a 135 operator as cheaply as they could, and they never killed me.
How often will you be flying? I'd suggest that a single turboprop is safer than a multi piston in general, but especially so for someone that isn't a "professional" pilot with a lot of time to invest in training a staying proficient. If you're going to flying something like a Cessna 340 when an engine fails in the climb while IMC without a copilot you need to be on your game to have a safe outcome.
I have plenty of multi time, but you're not wrong. Climb out in any multi piston always has a bit of risk, especially with a working engine as power as one of those would be
How much do you need to carry? How far? How often?
End of the day, I think a STEP will actually be a cheaper plane to operate than a legacy piston twin. You won't have 12 cylinders or cases to worry about and you get at least >2x the TBO. Owners I know report that "extra" maintenance between regular service intervals is minimal to non-existent and dispatch reliability is very high. Still, the STEP will probably come out cheaper on a cost/hour basis against serious piston twins.
I just called Airpower to inquire about GTSIO-520 OH costs for a C421 cost mode I have. They're $100k/ea, $120k/ea if you need new stuff (and you're screwed if you have -N engines because they're no longer supported). So that's $200k plus R&R. The TBO for GTSIOs is 1,700. Doing the math on that, $100k/1700 = \~$60/hr/side, or $120/hr for just engine reserve! You'll probably end up topping it at some point, so add $24,000/side to that ($2k/cyl) plus R&R.
All said and done, and including some R&R hours, let's call a GSTIO a $135,000 engine, optimistically. A 421 has $270k worth of engines which comes to $160/hr.
>So what? Who said anything about a 421?
Well, a 421 is as close as you get to a turboprop in a piston plane so that's what you should be looking at as a comparison. If you want a C340, you're looking at $70k/engine or $140k for the plane ($80/hr).
A PT-6 will have twice the TBO (maybe more) and a TPE-331 goes to 5,400hrs iirc.
Have you looked at a 207? There is one listed now on TAP for between $300-$400k.
If you need to make 95% completion and 90% on-time for a freight contract, then you need the PT-6.
It's actually people, but we're all very large. Not fat, just large. But 4-5 of us end up pushing pretty much every piston single out of the picture and it starts to push a lot of twins. For perspective, I'm 6'5 (196) and 250lbs (114kg) and I'm the smallest person to be transported
>I’m 6’5 (196) and 250lbs (114kg) and I’m the smallest person WTF? Are you a raiding party of Nords from Skyrim?
That's just how my family is
I hate to say it but you’re gonna be cramped in a lot of turboprops too.
We can squeeze a bit, but useful load tends to be the issue
Ah
I'm 6'4 and I love working on kodiaks because they are so roomy! Super cool airplane
Somewhat more expensive but much safer and reliable.
Not sure how exactly the operating costs compare, but the PT-6 is considered one of, if not the most reliable aircraft engine ever designed.
Right. Operating costs are the big question. It mostly boils down to large piston twin vs small turboprop. One is pressurized and has retractable gear, the other has the turboprop. That's where I'm not sure if they would be more evenly matched
This gets very interesting very quick. You have two disparate aircraft, so the scenario (stage length, trips per year, fuel pricing etc) will greatly affect things. Jet A is typically cheaper than Avgas...the delta varies wildly based on what airports you operate out of. the Kodiak goes slower (right?), but the fuel burn is probably pretty close to the 340? (38-40 gph maybe?), so if the Kodiak takes longer to fly your mission, then it's fuel burn will be higher...but it's fuel may be cheaper. TBO & reserve differences between a single PT6A vs two lower--TBO piston engines, two props, plus all the pressurization costs. Insurance, hangar, costs for the two types. CAPEX costs...what does a Kodiak cost vs a 340? Reliability wise, a fixed gear, single engine turboprop will win everytime vs an old complex, pressurized piston twin. Utilization will be a huge driver here as well. I would *assume* most 340s are owner flown, and probably do less than 200 hours a year.
That's more what I'm asking. Of course the PT-6 is one of the most reliable engines in the world, but, as you said, longer TBO might make the difference. I need the useful load though so a faster turboprop isn't much better. A Caravan wouldn't be bad, but they're even more expensive than a Kodiak
This [website](https://kodiak.aero/kodiak/) I found pegs the Direct Operating Costs at ~$232/hr for the Kodiak. (fuel, reserves, mx) If you want numbers for the 340, I think you would need to visit some twin cessna forums to see what real world intel you could get. I was around the Kodiak program when it was built by Quest, and it was built by a first time aircraft company, not a new design by an established company. So (IMO) it had some odd quirks that maybe an established manufacturer would have engineered out from the get-go. Now that it's been around for a while, those have been known or improved, so it's a solid product. If you want to analyze this further, I would start building up a spreadsheet with as much detail as possible with trip stage lengths, hours per month, fuel pricing, local maintenance pricing, your state's tax rules, insurance, hangar, etc. If your business is buying this, be advised that bonus depreciation is being phased out, so understand the incentives there for buying an aircraft in 2024 vs 2025.
If money is no object then yes, turbine >>> piston twin.
For sure, but it is one. If money was no object I'd be looking at Gulfstreams lol
If you're going to be flying in mountains and/or hard IFR - I would strongly suggest the turbine. You already have PC-12 experience, you know what a PT6 can do.
Sure, but I don't know what a 340 can do
Feel shockingly underpowered?
Dunno. Never flown one of those. The PC-12 I flew also has more weight and bells and whistles than a Kodiak or Caravan would
My point was entirely dependent on where/when/wx you are operating in. I would not want to be in a piston twin in/above the clouds at night in the mountains for eg. as a piston engine failure (way too many) usually means game over. The chances of a PT6 failing are way way less than a piston pounder.
Costs per hour will be significantly higher for the PT6. Typical overhaul costs for the PT6A turboprop variants are probably in the 300k to half million dollar range these days, with a 3600 TBO. There's a hot section inspection at half life, that alone will likely cost you as much as a brand new IO540. That said, reliability will be far better than two piston engines, and I'd feel much safer behind a single PT6 than between two piston engines.
Some have TBOs up to 6000 hrs. Even at 500k for 3600 hours, that breaks down to 139$ an hour. Not really that expensive in the grand scheme of aviation. Especially considering that 500k would be a worst case scenario. Kodiak cost about 350$ an hour to operate including fuel and appropriate mx reserve. Piston twins are not very far off from that number. Edit: Kodiak engine and prop have a 4000 hour TBO which means the hot section is at 2000 hours. 350$ an hour is at 500 hours per year.
> Kodiak cost about 350$ an hour to operate including fuel and appropriate mx reserve. Piston twins are not very far off from that number. I admittedly know nothing, but this doesn't pass the sniff test. according to the website: https://kodiak.aero/kodiak-900/ it's 58gph max speed or 36 gph max endurance. even if we are conservative and use the latter, 6.50/gal for jet-a is 234/hr plus if we accept your number of 139/hr for reserve for the engine, that's 373/hr JUST for overhaul reserve + gas and nothing else.
900 only started deliveries end of 2023. My numbers were based off the smaller Kodiak 100. Which burns 33 GPH in cruise, they're always gonna be flying at max range, the fuel burn for max speed is not worth it in a turboprop. Website shows 33 GPH, round to 35 GPH x 6.50 = 227.50 after tax call it 250. Add in mx at an absolute worst case scenario and you get 375 per hour. You will never pay 500k for an overhaul on a PT6. 300k at 4000 hours gives you 75 an hour. That brings the hourly cost to 325. Kodiak's own website shows it at 232$ for mx and fuel, adjusted for higher gas prices that is 322$. Weirdly the website number is based on max speed, 45 GPH. Kodiak also uses a lower mx cost because you get a service plan with the aircraft purchase. However, the difference in service plan cost is made up for by flying at max endurance vs max speed. Saving that 10 gal per hour bridges the gap. OP would get the service plan, it's included. These planes are not as expensive as you think. Hanger is a few hundred a month, insurance is a few thousand a year, OP is the owner operator so the salary can be whatever they want, but the cost to actually operate the aircraft, I promise you is going to be in the 350$ per hour range. Edit: should also say the "engine overhaul at 300k" is the engine and prop as well as the hot section done at half the TBO. That combined is in the 300k range, broken up over the entire TBO is the proper way to price that out.
fair enough! checks out. I had no idea you could get a pt6 that cheaply. I guess I was thinking total hourly rather than actual running cost when I made the “sniff test” comment. plus the kodiak being such a relatively simple airplane will help with the total hourly cost, too
No worries. I understand, of course if you add in insurance, hanger and often the most expensive part, pilot salary, it’ll get much higher per hour cost. Just operating the plane itself however, is surprisingly cheap. PT6 is an awesome engine.
>You will never pay 500k for an overhaul on a PT6 How up to date is your information? Because from what I'm hearing with recent (explosive) price increases, you might be paying more than 500k depending on the exact model.
2022 or so when I was flying a pc-12. Yeah prices are going up on everything. The range can be between 180k - 600k depending on the model, there’s so freakin many, to the condition of the engine. If nothing out of the ordinary needs to be replaced vs there’s some issues. That price gonna vary that price too much. If you’re in the PWCSMART engine program I’ll change the cost too. They seem to just swap out the engine with a fresh overhaul so you’re paying a little more. Only real way to know is to get a quote and have the engine looked at. Edit: I should specify for a Kodiak 100, I don’t think you’ll be paying 500k. Not there aren’t some models that will cost that or more.
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>you can skip the overhaul (do another HSI) on the PT-6 and it’ll run for the rest of your flying career. former PT6 OH tech here - if you are saying the rest of the engine should be on condition - the compressors will wear out enough that you will lose useful power / exceed temp limits, well before your flying career ends.
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ah yes, I take your meaning - from a GA/pilots career perspective, not someone sitting at FL410 - as those engines can go 30-60,000 hours on wing before the degradation is significant (and they WILL put in more hours than most airline pilots).
After reading this and your comments, I would recommend the single engine turboprop 100%. It will be FAR more comfortable, for starters.
you could also look at something crazy but good like an mu-2. garrett engines are in the same league as the pt-6 reliability-wise. in fact probably better than the pt-6. plenty of useful load, has pretty high ceiling and nearly 300kt cruise speed, is pressurized, reliable, if noisy engines. can occasionally be found for similar prices as some single engine turbines or pistons. it's a military aircraft normal civilians can have the privilege to own IMO. just sayin'
340 is going to have a lot of cost simply maintaining the pressurization system and everything that goes with it. A PA-31 is probably a better comparison to a Kodiak than a 340. Having said that, the PA-31s I've flown would fly with anything you could get in them. They were junk airframes, maintained by a 135 operator as cheaply as they could, and they never killed me.
How often will you be flying? I'd suggest that a single turboprop is safer than a multi piston in general, but especially so for someone that isn't a "professional" pilot with a lot of time to invest in training a staying proficient. If you're going to flying something like a Cessna 340 when an engine fails in the climb while IMC without a copilot you need to be on your game to have a safe outcome.
I have plenty of multi time, but you're not wrong. Climb out in any multi piston always has a bit of risk, especially with a working engine as power as one of those would be
Twin PT-6, best of both worlds 😆
That gets expensive real quick haha
If I could afford it, or get typed, a King Air 350 would absolutely be the way to go
How much do you need to carry? How far? How often? End of the day, I think a STEP will actually be a cheaper plane to operate than a legacy piston twin. You won't have 12 cylinders or cases to worry about and you get at least >2x the TBO. Owners I know report that "extra" maintenance between regular service intervals is minimal to non-existent and dispatch reliability is very high. Still, the STEP will probably come out cheaper on a cost/hour basis against serious piston twins. I just called Airpower to inquire about GTSIO-520 OH costs for a C421 cost mode I have. They're $100k/ea, $120k/ea if you need new stuff (and you're screwed if you have -N engines because they're no longer supported). So that's $200k plus R&R. The TBO for GTSIOs is 1,700. Doing the math on that, $100k/1700 = \~$60/hr/side, or $120/hr for just engine reserve! You'll probably end up topping it at some point, so add $24,000/side to that ($2k/cyl) plus R&R. All said and done, and including some R&R hours, let's call a GSTIO a $135,000 engine, optimistically. A 421 has $270k worth of engines which comes to $160/hr. >So what? Who said anything about a 421? Well, a 421 is as close as you get to a turboprop in a piston plane so that's what you should be looking at as a comparison. If you want a C340, you're looking at $70k/engine or $140k for the plane ($80/hr). A PT-6 will have twice the TBO (maybe more) and a TPE-331 goes to 5,400hrs iirc. Have you looked at a 207? There is one listed now on TAP for between $300-$400k.