Brand new... Old Yank metal -v- new plastic fantastic.
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Brand new... Old Yank metal -v- new plastic fantastic.
Times seem to be a changing so would anyone buy a brand new aircraft based on a 40 or 50 year old design from Cessna / Piper / Beech / Mooney /etc rather than one of the newer designs?
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“Times seem to be a changing so would anyone buy a brand new aircraft based on a 40 or 50 year old design from Cessna / Piper / Beech / Mooney /etc rather than one of the newer designs?”
This is a subject, which comes up on a regular basis, so you may want to do a search. Personally, no I would not touch a 50 year old design, particularly if it had a 60 + year old engine to go with it.
You then get into the IFR V VFR debate. I sold my AA5B and built a Plastic fantastic, which is VFR day only but does 138kn on 15 lph of mogas and will lift two 90kg people with 4 hours plus fuel. It gets me round Europe and I have more fun, but others will say you have to go with an IFR 4+ seats etc. It depends on your mission profile. I would rather have new Cirrus than a new 172, but I would rather have my MCR01 over both.
Rod1
This is a subject, which comes up on a regular basis, so you may want to do a search. Personally, no I would not touch a 50 year old design, particularly if it had a 60 + year old engine to go with it.
You then get into the IFR V VFR debate. I sold my AA5B and built a Plastic fantastic, which is VFR day only but does 138kn on 15 lph of mogas and will lift two 90kg people with 4 hours plus fuel. It gets me round Europe and I have more fun, but others will say you have to go with an IFR 4+ seats etc. It depends on your mission profile. I would rather have new Cirrus than a new 172, but I would rather have my MCR01 over both.
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When it comes to damage repair the more I have to do with Plastic the more I like metal!
Plastic is very unforgiving and I can't help thinking that we are about to have a spate of problems resulting from a lack of correct inspection and repair of plastic structurers, some of these resulting from poor instructions from American manufactures who's repair knowlage is light years behind the European industry.
Plastic is very unforgiving and I can't help thinking that we are about to have a spate of problems resulting from a lack of correct inspection and repair of plastic structurers, some of these resulting from poor instructions from American manufactures who's repair knowlage is light years behind the European industry.
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Of course, if GA aircraft had a similar lifespan/depreciation curve to cars, the would be no contest; we would all move on to the new generation of tourers, such as Cirrus, Diamond, Columbia et al.
As to who it is who buys NEW Pipers, Cessna's or Socata's (perhaps this is a bad example, as I don't know if new Socata's are still produced - IO540?), it is probably either flying schools or rental organisations adding to an existing fleet of similar a/c, or cynical end users who distrust the new technology (sometimes with good reason) who don't feel like doing long term product development for the manufacturers.
The more usual choice for sole operaters like me is that of a 20-30 year old machine, but one which has been refurbished top to bottom. If you factor in new paint, avionics, interior and engine, all you are left with is the airframe that dates back 20/30 years, the other componants being the new section of "the woodmans favorite axe".
So, £50-80,000 for a spanking refurbed bit of well understood old technology - with depreciation following a Sine wave (about a median line dictated by maintenance) or £250-300,000 with depreciation like an anvil out of a window and new technology?
As to who it is who buys NEW Pipers, Cessna's or Socata's (perhaps this is a bad example, as I don't know if new Socata's are still produced - IO540?), it is probably either flying schools or rental organisations adding to an existing fleet of similar a/c, or cynical end users who distrust the new technology (sometimes with good reason) who don't feel like doing long term product development for the manufacturers.
The more usual choice for sole operaters like me is that of a 20-30 year old machine, but one which has been refurbished top to bottom. If you factor in new paint, avionics, interior and engine, all you are left with is the airframe that dates back 20/30 years, the other componants being the new section of "the woodmans favorite axe".
So, £50-80,000 for a spanking refurbed bit of well understood old technology - with depreciation following a Sine wave (about a median line dictated by maintenance) or £250-300,000 with depreciation like an anvil out of a window and new technology?
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So, £50-80,000 for a spanking refurbed bit of well understood old technology - with depreciation following a Sine wave (about a median line dictated by maintenance) or £250-300,000 with depreciation like an anvil out of a window and new technology?
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Fuel efficiency is certainly becoming the elephant in the living room and is a valid point. I, from my limited experience, don't forsee a happy future for thirsty twins.
As for the "benefits" of new technology - "eg. BRS parachutes, G1000 situation awareness & ease of use, FADECs", all of these are arguably double edged swords; For example;
BRS parachutes - great idea, but are they sometimes used as a substitute for airmanship?
G1000 situation awareness - terrific and I'm a real fan of GPS. Others on this forum will argue equally passionately against GPS for a huge variety of reasons.
FADEC's - A tricky one. I think that what strikes me from reading the Theilert engined sections of GASILS is how often mysterious engine management problems seem to manifest themselves, only for the factory, upon investigating said problems, only to find nothing. Are they fixing the problem and keeping quiet? Is the problem fixing itself? Is the problem a result of mis-handling? Dunno. I for one would prefer to retain a major degree of control over vital systems until this technology is fully developed and gilt-edged; if that entails me staying in the dark ages of magneto's for now, so be it.
To have a "computer says no" situation on a comedy sketch in the comfort of your living room is amusing. To have it on the climb-out into IMC is probably not.
I am now going to my bunker and reaching for my hard hat....
As for the "benefits" of new technology - "eg. BRS parachutes, G1000 situation awareness & ease of use, FADECs", all of these are arguably double edged swords; For example;
BRS parachutes - great idea, but are they sometimes used as a substitute for airmanship?
G1000 situation awareness - terrific and I'm a real fan of GPS. Others on this forum will argue equally passionately against GPS for a huge variety of reasons.
FADEC's - A tricky one. I think that what strikes me from reading the Theilert engined sections of GASILS is how often mysterious engine management problems seem to manifest themselves, only for the factory, upon investigating said problems, only to find nothing. Are they fixing the problem and keeping quiet? Is the problem fixing itself? Is the problem a result of mis-handling? Dunno. I for one would prefer to retain a major degree of control over vital systems until this technology is fully developed and gilt-edged; if that entails me staying in the dark ages of magneto's for now, so be it.
To have a "computer says no" situation on a comedy sketch in the comfort of your living room is amusing. To have it on the climb-out into IMC is probably not.
I am now going to my bunker and reaching for my hard hat....
Maybe down south more of you can but I imagine not many of us up here will be making a queue
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It is a lot of money on your own, but 50k from 5 people and you are away. Alternatively you can go PFA, slash the cost down to an affordable amount and save a bundle on running costs.
Rod1
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I think there are a few distinctions that you need to make here. You can't just simply compare old with new. Sometimes you may have to combine old with new to get your perfect compromise.
Aluminium vs. "plastic" (composite) airframe:
- Lots of experience with long-term behaviour of aluminium structures, both when it comes to (outside) storage and repair. Far less experience in general with composite structures in this respect, outside the sailplane community. And gliders are normally stored indoors - despite UV protective paint, will a composite aircraft like a DA-40 really survive 30 years plus of being stored outdoors? With aluminium, we know that this can be done, provided that certain precautions are taken. With composites, we think it can, but the technology hasn't been around long enough to prove that it can be done.
- Advantage of composite is that it can be formed in two dimensions, which is very hard to do with aluminium. This leads to aerodynamically better designs. Plus: no rivets.
Lycoming/Continental vs. Rotax vs. Thielert
- Direct drive engines like Lycoming and Continental are very robust but need large internal displacements to produce their horsepowers. This is fuel inefficient. Engines with a gearbox like Rotax and Thielert can run at higher revs, with smaller internal displacements, which makes them more fuel efficient.
- Water cooling is far more efficient than fuel/air cooling, but it comes with a price in weight and added complexity
- Diesel fuel (whether Jet-A or automotive diesel) has more energy density, both per liter and per kg than fuels like avgas and mogas, and are easier to refine, thus less expensive. Avgas is a niche market for fuel refineries and 100LL still contains a bit of lead, which upsets the environmentalists. Mogas has problems with European legislation requiring the addition of biofuels, most often alcohol/ethanol, which can cause vapor lock problems. Jet-A, as of yet, is tax exempt.
- FADEC (or whatever name you give it) has the advantage of making engine management, from the pilots perspective, far less involved. Just one lever instead of three (throttle, mixture, prop) to adjust and just one number (%load) instead of at least two (MAP, RPM) to see how much power the engine is developing. FADEC will keep track of engine health (temperatures, turbo pressure etc) for you and is able to store the data for later analysis. But FADEC requires a continuous electric supply which is external to the engine. Whereas magnetos are essentially integrated with the engine and will work regardless of what happens elsewhere.
BRS: Has to be designed/installed by the factory and both the airframe design and BRS design depend on each other. Obviously has a lifelong weight & maintenance penalty and in some cases there is indeed the perception that it is used instead of airmanship.
G1000 or similar - apart from the one-time expense, both in terms of money and training time, I really can't see a downside to this technology. Perhaps in training though: if you've been trained on integrated glass exclusively and then need to swap to steam gauges.
Fortunately, there are a lot of designs out there that combine these new technologies in different ways, and you can pick a design that's best for you. Eg.
Cirrus: Plastic, direct drive engine (don't know whether that's a Lyco or Cont), BRS, G1000
C172: Aluminium, available both with the original engine but also with a Thielert now, and a G1000 if you want to, but no BRS (that I know of)
PA28: See C172 although I do not know if the PA-28 can be equipped with a Thielert straight from the factory.
Diamond: Plastic, both a direct drive and the Thielert engine available, variety of panels, no BRS
A lot of VLA designs now use the Rotax 912, 912S or 914 instead of more traditional, direct drive engines like the smaller Continentals/Lycomings, or the Jabiru.
Aluminium vs. "plastic" (composite) airframe:
- Lots of experience with long-term behaviour of aluminium structures, both when it comes to (outside) storage and repair. Far less experience in general with composite structures in this respect, outside the sailplane community. And gliders are normally stored indoors - despite UV protective paint, will a composite aircraft like a DA-40 really survive 30 years plus of being stored outdoors? With aluminium, we know that this can be done, provided that certain precautions are taken. With composites, we think it can, but the technology hasn't been around long enough to prove that it can be done.
- Advantage of composite is that it can be formed in two dimensions, which is very hard to do with aluminium. This leads to aerodynamically better designs. Plus: no rivets.
Lycoming/Continental vs. Rotax vs. Thielert
- Direct drive engines like Lycoming and Continental are very robust but need large internal displacements to produce their horsepowers. This is fuel inefficient. Engines with a gearbox like Rotax and Thielert can run at higher revs, with smaller internal displacements, which makes them more fuel efficient.
- Water cooling is far more efficient than fuel/air cooling, but it comes with a price in weight and added complexity
- Diesel fuel (whether Jet-A or automotive diesel) has more energy density, both per liter and per kg than fuels like avgas and mogas, and are easier to refine, thus less expensive. Avgas is a niche market for fuel refineries and 100LL still contains a bit of lead, which upsets the environmentalists. Mogas has problems with European legislation requiring the addition of biofuels, most often alcohol/ethanol, which can cause vapor lock problems. Jet-A, as of yet, is tax exempt.
- FADEC (or whatever name you give it) has the advantage of making engine management, from the pilots perspective, far less involved. Just one lever instead of three (throttle, mixture, prop) to adjust and just one number (%load) instead of at least two (MAP, RPM) to see how much power the engine is developing. FADEC will keep track of engine health (temperatures, turbo pressure etc) for you and is able to store the data for later analysis. But FADEC requires a continuous electric supply which is external to the engine. Whereas magnetos are essentially integrated with the engine and will work regardless of what happens elsewhere.
BRS: Has to be designed/installed by the factory and both the airframe design and BRS design depend on each other. Obviously has a lifelong weight & maintenance penalty and in some cases there is indeed the perception that it is used instead of airmanship.
G1000 or similar - apart from the one-time expense, both in terms of money and training time, I really can't see a downside to this technology. Perhaps in training though: if you've been trained on integrated glass exclusively and then need to swap to steam gauges.
Fortunately, there are a lot of designs out there that combine these new technologies in different ways, and you can pick a design that's best for you. Eg.
Cirrus: Plastic, direct drive engine (don't know whether that's a Lyco or Cont), BRS, G1000
C172: Aluminium, available both with the original engine but also with a Thielert now, and a G1000 if you want to, but no BRS (that I know of)
PA28: See C172 although I do not know if the PA-28 can be equipped with a Thielert straight from the factory.
Diamond: Plastic, both a direct drive and the Thielert engine available, variety of panels, no BRS
A lot of VLA designs now use the Rotax 912, 912S or 914 instead of more traditional, direct drive engines like the smaller Continentals/Lycomings, or the Jabiru.
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To have a "computer says no" situation on a comedy sketch in the comfort of your living room is amusing. To have it on the climb-out into IMC is probably not.
More or less.....With the handheld radio and pocket GPS you are doing far better than some poor sod partial panel in a steam driven aeroplane.The plastic aeroplanes all come with 25G impact resistant cockpits and seats, and some have airbags. Look at the firewall of a Cessna, even a brand new one. If you stick that into a fence there is not a lot stopping the engine landing on your lap. Stick a DA40 into a fence and it has been designed to protect you (something they didn't even think about 50 years ago, in cars either).
The Titanic was built with not enough lifeboats beacuse it was unsinkable..... I'd rather be in a plastic rocket ship with BRS which has NOT been certified for spinning, than a aluminium spam can that has NOT been certified for spinning without one
Touch wood in the last 7 years I have not managed to get into an unintentional spin yet, even in mishandled aero's gone a bit skewy 
(because this is the arguement with BRS).
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Times seem to be a changing so would anyone buy a brand new aircraft based on a 40 or 50 year old design from Cessna / Piper / Beech / Mooney /etc rather than one of the newer designs?
To a large degree the question has already been answered. The old stuff isn't selling anymore.
Some aviation rag I picked up the other day (FTN?) said Piper sold just 14 PA28 Archers worldwide in 2006. Piper UK annual sales of piston planes have AIUI been in single digits for years, and it is only the occassional £1.5M turboprop that keeps the whole thing afloat; you don't need to sell a lot of those. Same with the Socata TB; production stopped in 2002 and only the £2M TBM is making money, and making plenty of it too. You need a £2M plane to absorb French trade union practices.
IMHO anybody buying a traditional Cessna or Piper is a fool. Well, a C182 is good for short strips while having reasonable touring ability. But an Archer? Who would pay £150k for something like that.
Mooneys have their followers, and some of them appear to be more aerodynamically efficient than most others; the narrower airframe perhaps? Personally, I don't like single door planes. Also if you look at some of the speed claims, they are way up at high oxygen flow rate altitudes (FL250) and silly fuel flow rates.
Composite is the future, like it or not.
But composites won't be here 30 years from now like the 1970s spamcans are still here. They won't last. Whether anybody will care is another matter, because buying a plane is a straight tradeoff between buying new (and spending next to nothing on airframe maintenance for 10-15 years) and buying old (and spending 4-5 digits annually).
The only reason we see so much old GA junk still flying is because the GA scene doesn't attract people with money to buy new stuff. Also, pilots are conditioned by the anoraks who dominate the GA scene that such and such 1970 piece of iron is actually really good. This will change too, I reckon, as things get modernised.
Personally, I would buy a TB20GT (year 2002/03) again. A fantastic plane, no handling vices, great looks, 2 doors, passengers absolutely love it. It's aluminium but the roof is composite. If you smash the roof you have a writeoff, but how would you smash the roof??
Then there is the lightweight VFR scene, 750kg or less depending on where. This is all composite anyway. These will gradually take over the VFR "sports" market, but are no good for serious mission capability which needs IFR/airways.
To a large degree the question has already been answered. The old stuff isn't selling anymore.
Some aviation rag I picked up the other day (FTN?) said Piper sold just 14 PA28 Archers worldwide in 2006. Piper UK annual sales of piston planes have AIUI been in single digits for years, and it is only the occassional £1.5M turboprop that keeps the whole thing afloat; you don't need to sell a lot of those. Same with the Socata TB; production stopped in 2002 and only the £2M TBM is making money, and making plenty of it too. You need a £2M plane to absorb French trade union practices.
IMHO anybody buying a traditional Cessna or Piper is a fool. Well, a C182 is good for short strips while having reasonable touring ability. But an Archer? Who would pay £150k for something like that.
Mooneys have their followers, and some of them appear to be more aerodynamically efficient than most others; the narrower airframe perhaps? Personally, I don't like single door planes. Also if you look at some of the speed claims, they are way up at high oxygen flow rate altitudes (FL250) and silly fuel flow rates.
Composite is the future, like it or not.
But composites won't be here 30 years from now like the 1970s spamcans are still here. They won't last. Whether anybody will care is another matter, because buying a plane is a straight tradeoff between buying new (and spending next to nothing on airframe maintenance for 10-15 years) and buying old (and spending 4-5 digits annually).
The only reason we see so much old GA junk still flying is because the GA scene doesn't attract people with money to buy new stuff. Also, pilots are conditioned by the anoraks who dominate the GA scene that such and such 1970 piece of iron is actually really good. This will change too, I reckon, as things get modernised.
Personally, I would buy a TB20GT (year 2002/03) again. A fantastic plane, no handling vices, great looks, 2 doors, passengers absolutely love it. It's aluminium but the roof is composite. If you smash the roof you have a writeoff, but how would you smash the roof??
Then there is the lightweight VFR scene, 750kg or less depending on where. This is all composite anyway. These will gradually take over the VFR "sports" market, but are no good for serious mission capability which needs IFR/airways.
Being new to powered GA and having spent more than a decade in road vehicle powertrain design, I have been amused and I suppose slightly horrified, by engines with carburettors and hence manual mixture control, manual intake air temperature control, no knock control, etc. Are the current production products from Lycoming and Continental still like that? As far as I can tell from those companies' web sites, fuel injection, etc. are at best add-ons and possibly not available at all. Can anyone explain why, please? I know one has to have more reliability in an aircraft but the full authority electronic throttle in your BMW (including Mini) is going to kill you and probably several other people if it fails open so basically it doesn't! This is ten year old car technology and aircraft FADEC is much older (we were designing it into RB211 at RR in the eighties). I am old enough to have had cars with manual chokes but anyone under 30 in Europe and probably 40 in the US will never have heard of such things. How many forced landings are caused by using such ancient technology? Would modern systems reduce or increase this? I don't know the answer but I am, being a techie and a spotter as well as a student PPL, very curious.
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Joe, welcome to the very conservative world of general aviation, where it takes a very long time for new technology to become certified, trusted and established (and not necessarily in that order).
In an aircraft, speed (and altitude) is life. In a car, speed kills. So if given the choice, an aircraft engine design will fail towards a "high power" setting, whereas a car engine design will fail towards the "no power" setting. The idea for an aircraft being that if you have such a failure, the engine will develop as much power as possible so that you can climb to altitude, or go into a climbing cruise, until you've come to an altitude and place where you can glide to a safe landing, hopefully at an airport with long runways. At that point in time you kill the engine.
I know one has to have more reliability in an aircraft but the full authority electronic throttle in your BMW (including Mini) is going to kill you and probably several other people if it fails open so basically it doesn't!
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Who can afford to shell out £250,000 for new plastic anyway? Maybe down south more of you can but I imagine not many of us up here will be making a queue.
Backpacker, good point.
No problem, you make the fail-safe mechanical spring pull the throttle blade open for an aircraft if motor control fails instead of closed which is what is done on a road vehicle.
No problem, you make the fail-safe mechanical spring pull the throttle blade open for an aircraft if motor control fails instead of closed which is what is done on a road vehicle.
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I would suspect that, given most GA products are consumed in the US of A, the fear of "Product Liability" suits has hampered the development of anything new from the Piper/Cessna, Lycoming/Continental camps. I.E. why change something proven for something new, when you can spend time concentrating on making it for less money instead?? Sad, but probably true.
The dominance of the PFA/LSA class by eastern european 2 seaters with rotax's up front promises to change the bottom end of the market quite dramatically; Maybe Cirrus and Diamond will do the same for the middle market.
On the subject of "the computer says no" I seem to remember Ian Seager of Flyer writing eloquently about a trip across the southern North Sea in a glass cockpit cirrus, only to have a minor lightning strike stun the avionics, leaving only a compass, AI and an altimeter to work from. Perhaps things have moved on...
However, even if I had the £250,000 necessary to buy an new 'plastic fantastic', I'd probably still go with an older airframe from one of the usual suspects (piper/socata/cessna) instead and spend some cash on bringing it up to 'as new' condition. I take onboard the comments about having to spend the difference on airframe bits but, against the depreciation cost of ownership from new or nearly new, this seems to be a price worth paying.
Just my opinion based on my limited experience of ownership.
The dominance of the PFA/LSA class by eastern european 2 seaters with rotax's up front promises to change the bottom end of the market quite dramatically; Maybe Cirrus and Diamond will do the same for the middle market.
On the subject of "the computer says no" I seem to remember Ian Seager of Flyer writing eloquently about a trip across the southern North Sea in a glass cockpit cirrus, only to have a minor lightning strike stun the avionics, leaving only a compass, AI and an altimeter to work from. Perhaps things have moved on...
However, even if I had the £250,000 necessary to buy an new 'plastic fantastic', I'd probably still go with an older airframe from one of the usual suspects (piper/socata/cessna) instead and spend some cash on bringing it up to 'as new' condition. I take onboard the comments about having to spend the difference on airframe bits but, against the depreciation cost of ownership from new or nearly new, this seems to be a price worth paying.
Just my opinion based on my limited experience of ownership.
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No problem, you make the fail-safe mechanical spring pull the throttle blade open for an aircraft if motor control fails instead of closed which is what is done on a road vehicle.
That's one of the reasons that magnetos are still used as well. Magnetos require a short circuit to be shut off. If the wire from the magnetos, through the firewall to the magneto switch breaks off for whatever reason, the magnetos are live.
Other examples are thermostatic valves in water-cooled engines that fail towards the setting that pushes the water through the radiator instead of bypassing it, and prop governors that fail towards fine pitch (in single engine airplanes) so that full power/RPM is available.
Last edited by BackPacker; 27th Nov 2007 at 14:18. Reason: Thought of more examples
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I don't think liability and certification are the problems they are constantly made out to be.
They just made brilliant excuses for sitting on one's ar*se because nobody has ever made money by overtaking the attitudes in their own market.
The reason current certified engines are old technology is because the main market - the USA - is very conservative and had always had cheap fuel.
Another thing is that these engines are not inefficient. If you burn a given fuel at peak EGT, or just slightly LOP, and the spark happens at about the right time, there isn't much more that can be done to improve efficiency. In a car that would be no good but that's because a car engine spends most of its time at say 20% power, so it has to be reasonably efficient over a large power range.
The real problem with the old Lycos etc is that they use thin metal sections (to save weight) and need careful management to avoid cracked cylinders etc. Lycoming etc have also had dreadful QA but that is a separate issue. Some of the design is also crap e.g. camshafts that don't get oil on them other than by splashing up, but this is nothing to do with efficiency...
If GA had been developed in Europe, things would be very different. Due to the historically hard to get IR, poor services etc, almost nobody in Europe flies for real and most activity is just for sports/fun, so you get e.g. the Rotax engine.
Attempts to use diesel car engines (Thielert, and ex Merc engine) have not been successful. The result is heavier than the old iron and so far much less reliable.
They just made brilliant excuses for sitting on one's ar*se because nobody has ever made money by overtaking the attitudes in their own market.
The reason current certified engines are old technology is because the main market - the USA - is very conservative and had always had cheap fuel.
Another thing is that these engines are not inefficient. If you burn a given fuel at peak EGT, or just slightly LOP, and the spark happens at about the right time, there isn't much more that can be done to improve efficiency. In a car that would be no good but that's because a car engine spends most of its time at say 20% power, so it has to be reasonably efficient over a large power range.
The real problem with the old Lycos etc is that they use thin metal sections (to save weight) and need careful management to avoid cracked cylinders etc. Lycoming etc have also had dreadful QA but that is a separate issue. Some of the design is also crap e.g. camshafts that don't get oil on them other than by splashing up, but this is nothing to do with efficiency...
If GA had been developed in Europe, things would be very different. Due to the historically hard to get IR, poor services etc, almost nobody in Europe flies for real and most activity is just for sports/fun, so you get e.g. the Rotax engine.
Attempts to use diesel car engines (Thielert, and ex Merc engine) have not been successful. The result is heavier than the old iron and so far much less reliable.