Ideas / suggestions for a twin
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He wants to replace a C206 - but almost everything that ever defied gravity has been suggested, except perhaps a DH84 Dragon and Executive A380!
You mentioned a C90 or Conquest - which is an enormous leap from a C206? Avoid the C90 with PT6A-20 engines. Consider an E90 with PT6A-28 engines. Conquest, well, you need to like Garrett engines.
A lesser known Cessna, the Cessna 425 Corsair/Conquest I with PT6A-112s is a very under rated twin, excellent engines and usually available at good prices. The RFDS successfully operated Cessna 425's in West Australia for many years. The 425 shares the same engine with the very similar but unpressired Reims F406 operated by Coatwatch.
Bear in mind that any aircraft fitted with two small PT6 turbine engines will cost you $215 per hour in engine, HSI, atarter generator etc overhaul provisions, or around $3.30 per nautical mile (at 240 kts) in basic operating costs. By comparison, a C206 will cost around $45 per hour in engine overhaul provision, but around $3.00 per nautical mile (at 125 kts) in basic operating costs.
You mentioned a C90 or Conquest - which is an enormous leap from a C206? Avoid the C90 with PT6A-20 engines. Consider an E90 with PT6A-28 engines. Conquest, well, you need to like Garrett engines.
A lesser known Cessna, the Cessna 425 Corsair/Conquest I with PT6A-112s is a very under rated twin, excellent engines and usually available at good prices. The RFDS successfully operated Cessna 425's in West Australia for many years. The 425 shares the same engine with the very similar but unpressired Reims F406 operated by Coatwatch.
Bear in mind that any aircraft fitted with two small PT6 turbine engines will cost you $215 per hour in engine, HSI, atarter generator etc overhaul provisions, or around $3.30 per nautical mile (at 240 kts) in basic operating costs. By comparison, a C206 will cost around $45 per hour in engine overhaul provision, but around $3.00 per nautical mile (at 125 kts) in basic operating costs.
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Tinstaafl - Terrific, thanks.
Tailwheel the 425 was actually one of the first aircraft that i looked into, perhaps the fact that there is presently none in the country was one reason that i didnt pursue it more. If you have any other operating figures for one then I would love to hear as they seem like quite a nice aircraft, feel free to PM. Also thats 155kt for the 206 thankyou very much!
Tailwheel the 425 was actually one of the first aircraft that i looked into, perhaps the fact that there is presently none in the country was one reason that i didnt pursue it more. If you have any other operating figures for one then I would love to hear as they seem like quite a nice aircraft, feel free to PM. Also thats 155kt for the 206 thankyou very much!
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Jack, thanks for your opinion.. Please keep your assumptions re: budget and maintenance/safety to yourself.
Why? Truth hurts does it? Are they aware of the risks you are taking by transporting them in a Cheiftain?
Still say going from a 206 to a PA31 just all seems wrong. 206 - great safer performer that wont get you into trouble. PA31 - new operator, horrific crash statistics in this scenario with a plane that will fly you to the crash site on one engine.
Suggest you read and do some more research - seen way too many of these things crash and burn.
A single engine TP like the Meridian will do 95% of the job and who says it needs constant maintenance. I know everybody has their own wheelbarrow to push but this "its got to be a twin" is all rubbish.
I just hope the operator isnt pushing the twin wheelbarrow for the sake of hours. Piston twins are precariously dangerous in inexperienced hands - way more than any turbo prop with one set of blades
Suggest you read and do some more research - seen way too many of these things crash and burn.
A single engine TP like the Meridian will do 95% of the job and who says it needs constant maintenance. I know everybody has their own wheelbarrow to push but this "its got to be a twin" is all rubbish.
I just hope the operator isnt pushing the twin wheelbarrow for the sake of hours. Piston twins are precariously dangerous in inexperienced hands - way more than any turbo prop with one set of blades
C 421 - yeah from 1968. Seriously we need to be thinking about modern aircraft that make sense in 2011. Yeah agree go the C208. I think the 208 is a more logical upgrade from a 206 than anything mentioned. I would also think a desirable thing to be based in Mildura.
I mean how would you feel if I pulled up in a HQ Holden taxi? Ok its got freesh paint and we did the head on the donk. Shes got new seat covers and its very presentable for it's age.
I mean how would you feel if I pulled up in a HQ Holden taxi? Ok its got freesh paint and we did the head on the donk. Shes got new seat covers and its very presentable for it's age.
TriMed, it doesn't matter what the multi-type is w.r.t. single engine performance if it's a Part 23 certified aircraft. They all lose ~70-90% of their two engine performance. Best you can do is start with something massively overpowered under normal circumstances so that whatever power reserve is left OEI is still sufficient.
NB. I had an in flight shutdown in that Panther Navajo a month or two ago when L.Eng. #2 Cyl injector line broke. At A090 I needed nearly max power to maintain altitude, at A080 climb power was needed, and at A060 I could maintain altitude at 75% power at Vyse+5. That's with an extra 25 hp above factory equipped.
On a side note, the EDM paid for itself that day. I'd been watching the EGT & CHT for that cylinder deteriorate for a while and was considering returning to base. All other EGTs & CHTs were normal. I thought it had a blocked injector. When the line broke I saw the EGT drop to 0 deg & CHT start reducing. No fire or smoke and, thanks to the EDM, I knew it was a particular cylinder. Didn't know at the time whether it was an injector, blocked/broken line, or swallowed a valve, cylinder break or what, so elected to shutdown the rough running engine and started back to base. With the EDM I could monitor the working engine's temps really accurately. I descended in stages until the live engine's temps were able to be maintained where they would normally be, and then airport hopped back to base. I had nearly full tanks & wanted to reduce that a fair bit before putting the wheels down. Fortunately there were so many airports in the area (East Coast Florida) that I was able to stay within a minute or two of a suitable strip the whole way back to base instead of circling the nearest & then landing.
Without the EDM to get some idea of what failed, and monitor the live engine I'd have landed at the nearest airfield so having it saved the owner from the expense of a grounded aircraft away from base + finding maintenance + transport + ferrying afterwards + the hassle factor.
NB. I had an in flight shutdown in that Panther Navajo a month or two ago when L.Eng. #2 Cyl injector line broke. At A090 I needed nearly max power to maintain altitude, at A080 climb power was needed, and at A060 I could maintain altitude at 75% power at Vyse+5. That's with an extra 25 hp above factory equipped.
On a side note, the EDM paid for itself that day. I'd been watching the EGT & CHT for that cylinder deteriorate for a while and was considering returning to base. All other EGTs & CHTs were normal. I thought it had a blocked injector. When the line broke I saw the EGT drop to 0 deg & CHT start reducing. No fire or smoke and, thanks to the EDM, I knew it was a particular cylinder. Didn't know at the time whether it was an injector, blocked/broken line, or swallowed a valve, cylinder break or what, so elected to shutdown the rough running engine and started back to base. With the EDM I could monitor the working engine's temps really accurately. I descended in stages until the live engine's temps were able to be maintained where they would normally be, and then airport hopped back to base. I had nearly full tanks & wanted to reduce that a fair bit before putting the wheels down. Fortunately there were so many airports in the area (East Coast Florida) that I was able to stay within a minute or two of a suitable strip the whole way back to base instead of circling the nearest & then landing.
Without the EDM to get some idea of what failed, and monitor the live engine I'd have landed at the nearest airfield so having it saved the owner from the expense of a grounded aircraft away from base + finding maintenance + transport + ferrying afterwards + the hassle factor.
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Tintaafl
That post is Gold!
To every aircraft owner, be it a single or twin, the best investment in safety, fault finding and reducing costs is to have a good engine monitor.
That post is Gold!
To every aircraft owner, be it a single or twin, the best investment in safety, fault finding and reducing costs is to have a good engine monitor.
You're not wrong about EDMs & pistons, Jaba. I used to fly this aircraft for a 135 charter mob. When they went tits up I took over managing it. That's when I recommended installing the EDM. I think they should be standard equipment on any piston.
For the typical flights we do, LOP operation adds 5 mins each way but saves over 30 USG for the round trip. Even though the aircraft is factory approved to run 50 deg LOP, doing so on the single point probe factory gauges is risky. You really need to know what's happening on each cylinder & the turbine. It's instructive to see how different power settings & mixture can change the most critical cylinder.
Being able to download each engine's parameters onto a USB stick is nice too. Really helps trend monitoring. It's a pity the unit (a JPI EDM760 without Fuel Flow) doesn't tap into the oil P&T's. Integral fuel flow would have been nice for data downloading but the extra cost wasn't justifiable considering it already had a digital FF fitted.
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1a...: Most pax can't tell if it's this year's model, or from 1970. If the aircraft's paint & interior are shiny & new then it's all the same to them, never mind what quality of maintenance has happened under the cowlings. About the only thing that most of the SLF know is if it has propellers then it's not a jet and therefore crashes 'all the time'. Not that that most of them are willing to pay jet charter rates. Some of the more astute ones have some idea about turboprops but by no means all. I've had to explain on the ramp/apron to somewhat peeved pax the Kingair they're going to fly in really does have a 'jet' engine like they booked, and not a 'dangerous' piston engine like 'all those small ones that crash all the time'.
Mind you, some of them can't even answer if the aircraft in which they flew was a single engine or a twin without prompting. Even those that fly in twins 'for safety' believe that any aircraft with two or more engines can fly perfectly well on only one of them at any stage of the flight.
For the typical flights we do, LOP operation adds 5 mins each way but saves over 30 USG for the round trip. Even though the aircraft is factory approved to run 50 deg LOP, doing so on the single point probe factory gauges is risky. You really need to know what's happening on each cylinder & the turbine. It's instructive to see how different power settings & mixture can change the most critical cylinder.
Being able to download each engine's parameters onto a USB stick is nice too. Really helps trend monitoring. It's a pity the unit (a JPI EDM760 without Fuel Flow) doesn't tap into the oil P&T's. Integral fuel flow would have been nice for data downloading but the extra cost wasn't justifiable considering it already had a digital FF fitted.
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1a...: Most pax can't tell if it's this year's model, or from 1970. If the aircraft's paint & interior are shiny & new then it's all the same to them, never mind what quality of maintenance has happened under the cowlings. About the only thing that most of the SLF know is if it has propellers then it's not a jet and therefore crashes 'all the time'. Not that that most of them are willing to pay jet charter rates. Some of the more astute ones have some idea about turboprops but by no means all. I've had to explain on the ramp/apron to somewhat peeved pax the Kingair they're going to fly in really does have a 'jet' engine like they booked, and not a 'dangerous' piston engine like 'all those small ones that crash all the time'.
Mind you, some of them can't even answer if the aircraft in which they flew was a single engine or a twin without prompting. Even those that fly in twins 'for safety' believe that any aircraft with two or more engines can fly perfectly well on only one of them at any stage of the flight.
Last edited by Tinstaafl; 5th Aug 2011 at 20:12.
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Purely a personal perspective, but a move to 30 plus year old PA31 and particularly C421 would be a retrograde step. A used C208 (the Baby Van) would be a far smarter, multi purpose solution for the wise investor, IF the C208 meets the operational criteria.
However, acquisition of an aircraft can only be based upon operational requirements, financial constraints and anticipated utilisation, not the pilot's personal flying ambitions. In 100 posts I can't find where the operational requirements have been defined, although I have not been closely following the thread.
TriMedGroup, I think you need to study up on aircraft operating cost analysis and in particular, the various cost elements that contribute to fixed and variable aircraft operating cost components, define your operational parameters - sector lengths, strip types, maintenance logistics etc - then determine which airframes may meet those constraints?
However, acquisition of an aircraft can only be based upon operational requirements, financial constraints and anticipated utilisation, not the pilot's personal flying ambitions. In 100 posts I can't find where the operational requirements have been defined, although I have not been closely following the thread.
TriMedGroup, I think you need to study up on aircraft operating cost analysis and in particular, the various cost elements that contribute to fixed and variable aircraft operating cost components, define your operational parameters - sector lengths, strip types, maintenance logistics etc - then determine which airframes may meet those constraints?
On another note I am interested in just how much better say a C90 or C441 is on a hot day when full over the cabin class pistons? I ask this as while i was in Canberra a few weeks back there was a Conquest obviously doing an endorsement or flight test as they advised being assy on take off. Anyway once airborne at about 800' or so it slowed up quite a bit and climb seemed to cease basically heading straight for the hills.
The PA31 on the other hand will be going down in these conditions. The PA31 was only ever required to achieve 1% climb gradient on one engine in ISA at MTOW. This is about 106 fpm at blue line with a feathered engine. Someone only has to fart on their seat and she will lose that rather quickly. Never mind thermals or incorrect technique or the temperature actually being greater than 15 degrees
Last edited by The Green Goblin; 5th Aug 2011 at 04:28.
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A quick holiday in Broome should yield plenty of folk operating the C208 who could advise you on the real costs.
I know two private companies who operate/d C208/C208B and do a bit of charter as well. One has recently gone up to the PC12, it seems the smart choice.
Do the numbers as TW suggests, and then get the budget to do it properly. Or stick to the C206.
J
I know two private companies who operate/d C208/C208B and do a bit of charter as well. One has recently gone up to the PC12, it seems the smart choice.
Do the numbers as TW suggests, and then get the budget to do it properly. Or stick to the C206.
J
The PA31 on the other hand will be going down in these conditions. The PA31 was only ever required to achieve 1% climb gradient on one engine in ISA at MTOW. This is about 106 fpm at blue line with a feathered engine. Someone only has to fart on their seat and she will lose that rather quickly. Never mind thermals or incorrect technique or the temperature actually being greater than 15 degrees
PLEASE to the OP consider a 208
Quote:
The PA31 on the other hand will be going down in these conditions. The PA31 was only ever required to achieve 1% climb gradient on one engine in ISA at MTOW. This is about 106 fpm at blue line with a feathered engine. Someone only has to fart on their seat and she will lose that rather quickly. Never mind thermals or incorrect technique or the temperature actually being greater than 15 degrees
Thankyou. The #2 engine merely is there for an uncontrolled crash at the landing site.
PLEASE to the OP consider a 208
The PA31 on the other hand will be going down in these conditions. The PA31 was only ever required to achieve 1% climb gradient on one engine in ISA at MTOW. This is about 106 fpm at blue line with a feathered engine. Someone only has to fart on their seat and she will lose that rather quickly. Never mind thermals or incorrect technique or the temperature actually being greater than 15 degrees
Thankyou. The #2 engine merely is there for an uncontrolled crash at the landing site.
PLEASE to the OP consider a 208
I lost a Pilot friend in a Mojave recently. While the second engine took him to his end, he did have drift down options until the only option was a crash.
At least through robust discussion after the incident I'm sure many piston twin drivers will now stay high if in the same position for as long as they can, rather than a standard descent profile to their suitable landing destination.
Food for thought?
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Tinstaafl, agree 100% on the engine monitoring, we have decided regardless of the aircraft choice that an EDM960 is going in - don't think i could go back to not knowing what the engine/s were doing in regard to temps having been exposed to all cylinder monitoring.
tail wheel the average trip is between 100-350NM with some as little as 50-60NM, and between 1 and 5 pax with an average weight including bags of 95KG pp. Strips are anything between Taggerty and Canberra sized, obviously Taggerty is out with anything much bigger than the 206!, therefore it would most likely be staying in the stable as 155Kt at under $200 an hour its pretty hard to beat for 1-2 pax.
I'm not disagreeing with what anyone has said merely engaging in debate when I say this but;
The 208 was designed around 1980? Hardly 'new' design technology - maybe not a HQ but certainly could be a WB taxi! Agree that it is a wonderful piece of equipment, don't think for a minute that i haven't done my research - I started long before this thread which began in December of last year I think.
Say going into Canberra cruising at 9000 in IMC over a segment with a 7200 Lsalt in the van and the fan stops? Is it still better than a piston twin? No doubt both are going down but what is the glide ratio of a heavy 208 V the drift down rate of descent in a heavy PA31 with one engine inoperative? Only talking about the Van here obviously in a pressurised single turbine you have a lot more options from FL180+
Jaba - any chance you could divulge any more details of said companies? via PM would be great. I have spoken to a few operators / former operators of the Van already and the feedback was that it was very hard to sell S/E turbine over a twin of any sort operated by the competition - even VFR.
Once again its not a long term investment solely for the purpose of making $$ in charter. Primary use is that of a company that has 30+ sites in different towns throughout VIC and NSW and transporting people between them, some of the operations that we conduct cannot be classified as Private hence the AOC so if we want to be less restricted in the conduct of these ops - IFR / Night then a new aircraft is required, i say again the AOC is not solely for the purpose of making money carting around the general public. I will also say again YES I KNOW ABOUT ASEPTA, by the sound of it a bit more than those who keep thinking it is a matter of sending a Form 1214 to CASA and you are right to go. Perhaps it is the way to go? Who knows, this is why we still haven't bought an aircraft! Believe me I would rather fly a Pilatus than a PA31. The problem being that the 206 has been outgrown and the PC12 is a massive leap, and perhaps overkill for a day trip to Warracknabeal. Where as a PA31 would be a lot comfier and quicker as an easy step up from the 206.
Thanks and regardless of what Aircraft type you think we should get, can someone answer my question about the VG kits and other mods in relation to MTOW's and performance??? No I'm not relying solely on an internet forum for the answers and should I find out before someone here posts anything I will let you know.
Thanks, Alistair.
tail wheel the average trip is between 100-350NM with some as little as 50-60NM, and between 1 and 5 pax with an average weight including bags of 95KG pp. Strips are anything between Taggerty and Canberra sized, obviously Taggerty is out with anything much bigger than the 206!, therefore it would most likely be staying in the stable as 155Kt at under $200 an hour its pretty hard to beat for 1-2 pax.
I'm not disagreeing with what anyone has said merely engaging in debate when I say this but;
The 208 was designed around 1980? Hardly 'new' design technology - maybe not a HQ but certainly could be a WB taxi! Agree that it is a wonderful piece of equipment, don't think for a minute that i haven't done my research - I started long before this thread which began in December of last year I think.
Say going into Canberra cruising at 9000 in IMC over a segment with a 7200 Lsalt in the van and the fan stops? Is it still better than a piston twin? No doubt both are going down but what is the glide ratio of a heavy 208 V the drift down rate of descent in a heavy PA31 with one engine inoperative? Only talking about the Van here obviously in a pressurised single turbine you have a lot more options from FL180+
Jaba - any chance you could divulge any more details of said companies? via PM would be great. I have spoken to a few operators / former operators of the Van already and the feedback was that it was very hard to sell S/E turbine over a twin of any sort operated by the competition - even VFR.
Once again its not a long term investment solely for the purpose of making $$ in charter. Primary use is that of a company that has 30+ sites in different towns throughout VIC and NSW and transporting people between them, some of the operations that we conduct cannot be classified as Private hence the AOC so if we want to be less restricted in the conduct of these ops - IFR / Night then a new aircraft is required, i say again the AOC is not solely for the purpose of making money carting around the general public. I will also say again YES I KNOW ABOUT ASEPTA, by the sound of it a bit more than those who keep thinking it is a matter of sending a Form 1214 to CASA and you are right to go. Perhaps it is the way to go? Who knows, this is why we still haven't bought an aircraft! Believe me I would rather fly a Pilatus than a PA31. The problem being that the 206 has been outgrown and the PC12 is a massive leap, and perhaps overkill for a day trip to Warracknabeal. Where as a PA31 would be a lot comfier and quicker as an easy step up from the 206.
Thanks and regardless of what Aircraft type you think we should get, can someone answer my question about the VG kits and other mods in relation to MTOW's and performance??? No I'm not relying solely on an internet forum for the answers and should I find out before someone here posts anything I will let you know.
Thanks, Alistair.
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Gobler,
Risk mitigation, getting out of bed in the morning is probably the biggest risk you take all day.
It sounds to me like someone is promising the 2 engines is better than one bit when it's not necessarily so.
The glide characteristics of the Caravan are remarkable, risk mitigation: don't transport people at night etc.
Risk mitigation, getting out of bed in the morning is probably the biggest risk you take all day.
It sounds to me like someone is promising the 2 engines is better than one bit when it's not necessarily so.
The glide characteristics of the Caravan are remarkable, risk mitigation: don't transport people at night etc.
Gobler,
Risk mitigation, getting out of bed in the morning is probably the biggest risk you take all day.
It sounds to me like someone is promising the 2 engines is better than one bit when it's not necessarily so.
The glide characteristics of the Caravan are remarkable, risk mitigation: don't transport people at night etc.
Risk mitigation, getting out of bed in the morning is probably the biggest risk you take all day.
It sounds to me like someone is promising the 2 engines is better than one bit when it's not necessarily so.
The glide characteristics of the Caravan are remarkable, risk mitigation: don't transport people at night etc.
Single engine turbine aeroplanes are around for one reason. They are cheaper to operate than a twin engine turbine aeroplane.
Plain and simple.
Risk analysis may conclude that a single engine turbine aeroplane is just as safe as a twin engine piston aeroplane. However, CASA still require a sound application before IFR Charter/RPT approval is given for them.
A piston twin comes out of the box with the approval.
Something to think about maybe?
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TGG - thanks for summing up what I have been getting at. Not saying that I agree with the situation at all though. Does anyone know if a change is at all on the cards in regard to this? I know... Silly question.
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It sounds to me like someone is promising the 2 engines is better than one bit when it's not necessarily so.
The glide characteristics of the Caravan are remarkable, risk mitigation: don't transport people at night etc.
The glide characteristics of the Caravan are remarkable, risk mitigation: don't transport people at night etc.
The 208 was designed around 1980? Hardly 'new' design technology
As I have said many times before.
A Piston twin engine aeroplane gives you options. It is not a get out of jail card, and it does not have guaranteed performance like something certified under 20.7.1b.
If the aeroplane is serviced well, and the pilot is proficient and understands the limitations of the aeroplane, they can be flown safely. IMO more safely than a turbine single.
You just need to have a bit of a think about what you are going to do before you push those levers forward. i.e what am I going to do if the donk quits on takeoff, climb, cruise etc etc and where can I go enroute.
The only things going for a turbine single are the fact they are newer, have greater performance when everything is working properly and the systems and avionics are of a more modern variety.
When the donk stops and you're in the soup, all that modern equipment is not going to save your arse, it's just going to tell you where you are going to end up rather accurately
A Piston twin engine aeroplane gives you options. It is not a get out of jail card, and it does not have guaranteed performance like something certified under 20.7.1b.
If the aeroplane is serviced well, and the pilot is proficient and understands the limitations of the aeroplane, they can be flown safely. IMO more safely than a turbine single.
You just need to have a bit of a think about what you are going to do before you push those levers forward. i.e what am I going to do if the donk quits on takeoff, climb, cruise etc etc and where can I go enroute.
The only things going for a turbine single are the fact they are newer, have greater performance when everything is working properly and the systems and avionics are of a more modern variety.
When the donk stops and you're in the soup, all that modern equipment is not going to save your arse, it's just going to tell you where you are going to end up rather accurately