Plastic Fantastics - the future?
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I agree with deice above.
Every show I go to is packed with "plastic fantastic" planes, and I always have a good nose around them. They all have a Rotax up front, a Garmin 296 in the middle of the panel, and the better ones have one of those "miniature G1000" panels. Very slick.
But I can see how they get the performance. They strip out all they can - like a Morgan car - and use much thinner control fixtures and linkages. Yesterday I was at a show in Greece and the flaps on some Czech machine rotated on pins which were M4 bolts. That is about 1/3 of the shear strength of a TB20 flat hinge. The control linkages are straight off some hang glider. Basically it is hang glider technology but with some skin to make it look like a real plane.
And they do break - plenty often enough.
The aluminium (where they don't use a painted fabric) is so thin you could almost poke a finger through it.
One day, if this ever becomes legal, I might build myself a fully composite carbon/kevlar plane with a turbine up front. Fully IFR of course. FL300 ceiling, 1400kg MTOW giving a +3000ft/min climb, 250kt TAS at FL250. Rated to +/-10G.
Every show I go to is packed with "plastic fantastic" planes, and I always have a good nose around them. They all have a Rotax up front, a Garmin 296 in the middle of the panel, and the better ones have one of those "miniature G1000" panels. Very slick.
But I can see how they get the performance. They strip out all they can - like a Morgan car - and use much thinner control fixtures and linkages. Yesterday I was at a show in Greece and the flaps on some Czech machine rotated on pins which were M4 bolts. That is about 1/3 of the shear strength of a TB20 flat hinge. The control linkages are straight off some hang glider. Basically it is hang glider technology but with some skin to make it look like a real plane.
And they do break - plenty often enough.
The aluminium (where they don't use a painted fabric) is so thin you could almost poke a finger through it.
One day, if this ever becomes legal, I might build myself a fully composite carbon/kevlar plane with a turbine up front. Fully IFR of course. FL300 ceiling, 1400kg MTOW giving a +3000ft/min climb, 250kt TAS at FL250. Rated to +/-10G.
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Cirrus, Diamonds and Bambis are all plastic fantastics, but that is as far as the comparison goes.
The first are out of a different mould to the second.
The Cirrus feels solid, has a very efficient and effective safety cage that is light years ahead of even most 90s vintage aircraft. It has proven its worth in a number of accidents. The Diamonds would appear to perform as well, even if in my opinion they don’t feel quite as solid.
When I flew the Bambi for the first time I couldn’t believe how much the whole thing creaked and groaned (I know, less cream would help), but seriously it did. The lightness of the airframe translated into a lively ride.
Of course glass and carbon don’t change the laws of physics even if they help rewrite them. Energy absorbing panels and strong cages don’t come without some added weight, and the extra weight takes more energy to move.
I am a fan of the Aztec, even if my wallet is not these days. You feel it will go through anything but when they were building them Avgas was cheaper than bottled water.
Mainstream GA plastic fantastic aircraft will not give you the comfortable ride of an Aztec - that’s gone with the need for efficient aerofoils, but they will give you a reasonable ride. A Bambi will further compromise the ride but in return give even better efficiency.
Which will look after you should you have the misfortune to have an unplanned meeting with terra firma may be more questionable.
Our understanding of how to absorb energy and build effective cages has improved considerably since Piper designed the Apache - and they didn’t change much when they bolted on some bigger engines. The Aztec depends on bulk and is not helped by its much faster approach speed - but then it does have two engines capable of exceeding the performance of most singles on one.
The Cirrus and Diamond have modern passenger cells which are designed to absorb energy and substantial construction.
The Bambi doesn’t have substantial construction but I guess the designers have given some thought to how the frame might best absorb impact energy. It could be argued the lower approach speeds and hence less inherent energy on impact may compensate for the lightness of construction. Personally I doubt it - I prefer to fly a Diamond or a Cirrus for among other reasons I reckon they will look after to me better if I had to put the airframe to the ultimate test.
Horses for course I guess. If you are going to rewrite the laws of physics expect some compromises - you can make something light fast and efficient or you can make something heavy fast and inefficient but you cant do the first without some compromise of the structural integrity of the passenger cell even if you can make the spars as strong in each of the designs.
If I couldnt afford to fly a Cirrus, Diamond, Aztec or something similiar then I might fly a Bambi and then again I might call it a day.
The first are out of a different mould to the second.
The Cirrus feels solid, has a very efficient and effective safety cage that is light years ahead of even most 90s vintage aircraft. It has proven its worth in a number of accidents. The Diamonds would appear to perform as well, even if in my opinion they don’t feel quite as solid.
When I flew the Bambi for the first time I couldn’t believe how much the whole thing creaked and groaned (I know, less cream would help), but seriously it did. The lightness of the airframe translated into a lively ride.
Of course glass and carbon don’t change the laws of physics even if they help rewrite them. Energy absorbing panels and strong cages don’t come without some added weight, and the extra weight takes more energy to move.
I am a fan of the Aztec, even if my wallet is not these days. You feel it will go through anything but when they were building them Avgas was cheaper than bottled water.
Mainstream GA plastic fantastic aircraft will not give you the comfortable ride of an Aztec - that’s gone with the need for efficient aerofoils, but they will give you a reasonable ride. A Bambi will further compromise the ride but in return give even better efficiency.
Which will look after you should you have the misfortune to have an unplanned meeting with terra firma may be more questionable.
Our understanding of how to absorb energy and build effective cages has improved considerably since Piper designed the Apache - and they didn’t change much when they bolted on some bigger engines. The Aztec depends on bulk and is not helped by its much faster approach speed - but then it does have two engines capable of exceeding the performance of most singles on one.
The Cirrus and Diamond have modern passenger cells which are designed to absorb energy and substantial construction.
The Bambi doesn’t have substantial construction but I guess the designers have given some thought to how the frame might best absorb impact energy. It could be argued the lower approach speeds and hence less inherent energy on impact may compensate for the lightness of construction. Personally I doubt it - I prefer to fly a Diamond or a Cirrus for among other reasons I reckon they will look after to me better if I had to put the airframe to the ultimate test.
Horses for course I guess. If you are going to rewrite the laws of physics expect some compromises - you can make something light fast and efficient or you can make something heavy fast and inefficient but you cant do the first without some compromise of the structural integrity of the passenger cell even if you can make the spars as strong in each of the designs.
If I couldnt afford to fly a Cirrus, Diamond, Aztec or something similiar then I might fly a Bambi and then again I might call it a day.
Last edited by Fuji Abound; 15th Jun 2008 at 21:25.
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Stik:
So glad you like the Pioneer. Thanks for baby sitting it in my absence - I will hope to come over soon and take it back home!
Mariner9: We must compare aeroplanes some time - perhaps when you are next over at Tibenham!!
Skik's initial question is about technology. Questions about "will they still be flying in 30 years" kind of emphasises the dilema faced by GA. In no other area area of activity do we use 30 year old technology and make a virtue of it, nor to we shackle it to outdated and impractical regulations designed for another age.
For this reason I see traditional certified GA being sidelined by what for convenience can be termed sports aviation. Lighter regulation has allowed Permit/Experimental aircraft to develop cheaper lighter and technologically more advanced systems for aircraft which would have been, if not impossible, then certainly hugely expensive under traditional certification. The use of tradiional materials such as wood, fabric etc as compared to composits is probably less important than how they are used. When used as part of a modern design which is aerodynamically efficient you end up with an aircraft which is cheaper to build and to run and which will be hugely better equipped than a certified machine. Yes, it will have less load capacity than a C172 and will not be IFR capable like a TB20, but the harsh truth is that few pilots can afford a TB20 and many will struggle to buy into and run a C172. With some commentators talking of oil at >$200 a barrel by the end of the year flying thirsty traditional singles (never mind twins) is going to become even more of a minority pursuit than it is currently.
So glad you like the Pioneer. Thanks for baby sitting it in my absence - I will hope to come over soon and take it back home!
Mariner9: We must compare aeroplanes some time - perhaps when you are next over at Tibenham!!
Skik's initial question is about technology. Questions about "will they still be flying in 30 years" kind of emphasises the dilema faced by GA. In no other area area of activity do we use 30 year old technology and make a virtue of it, nor to we shackle it to outdated and impractical regulations designed for another age.
For this reason I see traditional certified GA being sidelined by what for convenience can be termed sports aviation. Lighter regulation has allowed Permit/Experimental aircraft to develop cheaper lighter and technologically more advanced systems for aircraft which would have been, if not impossible, then certainly hugely expensive under traditional certification. The use of tradiional materials such as wood, fabric etc as compared to composits is probably less important than how they are used. When used as part of a modern design which is aerodynamically efficient you end up with an aircraft which is cheaper to build and to run and which will be hugely better equipped than a certified machine. Yes, it will have less load capacity than a C172 and will not be IFR capable like a TB20, but the harsh truth is that few pilots can afford a TB20 and many will struggle to buy into and run a C172. With some commentators talking of oil at >$200 a barrel by the end of the year flying thirsty traditional singles (never mind twins) is going to become even more of a minority pursuit than it is currently.
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I agree with your analysis, Justiciar.
However, another thing will have to come into place if we are to ditch the "must last for 30 years" expectation: rapid and massive depreciation will be the norm, making current depreciation rates (which drive many owners up the wall) look like a picnic.
A Rotax will have to sell for as much as a car engine, for example. I think this is a very long way away.
It's obvious that 99% of GA is VFR-only (whether they stick to VMC is beside the point) and this is the problem facing IFR GA (like me) because it is such a small group it could easily become marginalised by the regulators.
I reckon that if it wasn't for ICAO, IFR GA would be dead and buried decades ago.
The bigger factor IMHO is land values, which will split UK GA into two scenes: airfields, and farm strips. I can see the strip scene going forward and doing OK, but the fact is that it is hard to set up a strip much over 500m, due to the way UK farmland has been split up over many years. I know, having looked into this in some length. Creating 1000m grass strips is incredibly hard work and that is before you try to get full planning and they discover the bits of hedges which you uprooted to get the 1000m
This factor alone will split GA into two groups of machines.
However, another thing will have to come into place if we are to ditch the "must last for 30 years" expectation: rapid and massive depreciation will be the norm, making current depreciation rates (which drive many owners up the wall) look like a picnic.
A Rotax will have to sell for as much as a car engine, for example. I think this is a very long way away.
It's obvious that 99% of GA is VFR-only (whether they stick to VMC is beside the point) and this is the problem facing IFR GA (like me) because it is such a small group it could easily become marginalised by the regulators.
I reckon that if it wasn't for ICAO, IFR GA would be dead and buried decades ago.
The bigger factor IMHO is land values, which will split UK GA into two scenes: airfields, and farm strips. I can see the strip scene going forward and doing OK, but the fact is that it is hard to set up a strip much over 500m, due to the way UK farmland has been split up over many years. I know, having looked into this in some length. Creating 1000m grass strips is incredibly hard work and that is before you try to get full planning and they discover the bits of hedges which you uprooted to get the 1000m
This factor alone will split GA into two groups of machines.
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IO540:
The land issue is a very interesting angle and I agree with your comments. One might expand that to consider the huge commercial pressures on all airfield operators to extract the maximum rent from land use to will increasingly force GA out of the medium sized airfields - here the ability to train from and get in and out of small unlicensed airfields and strips will become improtant as will the proposal to allow remuneration for flying instructors without needing to have a CPL. The GA scene needs more dedicated instructors who are not just marking time until an airline job comes up; it needs to encourage experienced pilots to become instructors without putting huge cost obstacles in their way.
Of course, many modern composites will happily get in an out of a 500 m strip, which again cannot be said of many modern certified aircraft!
One depreciation, I guess a number of points arise. First, the life of the modern VLA/Permit aircraft has not really been tested because many are too young so it is not easy to know over what period you should sensibly write off the cost. Secondly, the cost of a new Pioneer, Kitfox, Europa etc tends to be a lot less than a certified aircraft, so the actual depreciation may not be too much different and the initial capital outlay puts them much more witrhin reach of the private owner than a new Cessna, Piper etc.
The land issue is a very interesting angle and I agree with your comments. One might expand that to consider the huge commercial pressures on all airfield operators to extract the maximum rent from land use to will increasingly force GA out of the medium sized airfields - here the ability to train from and get in and out of small unlicensed airfields and strips will become improtant as will the proposal to allow remuneration for flying instructors without needing to have a CPL. The GA scene needs more dedicated instructors who are not just marking time until an airline job comes up; it needs to encourage experienced pilots to become instructors without putting huge cost obstacles in their way.
Of course, many modern composites will happily get in an out of a 500 m strip, which again cannot be said of many modern certified aircraft!
One depreciation, I guess a number of points arise. First, the life of the modern VLA/Permit aircraft has not really been tested because many are too young so it is not easy to know over what period you should sensibly write off the cost. Secondly, the cost of a new Pioneer, Kitfox, Europa etc tends to be a lot less than a certified aircraft, so the actual depreciation may not be too much different and the initial capital outlay puts them much more witrhin reach of the private owner than a new Cessna, Piper etc.
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I'm probably biased because I often plan IFR but I never cease to be amazed by the high second hand price asked for some homebuilt aircraft compared with an IFR equipped 4 seater.
DO.
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“I'm probably biased because I often plan IFR but I never cease to be amazed by the high second hand price asked for some homebuilt aircraft compared with an IFR equipped 4 seater.”
As has been said, 99% of UK pilots are VFR only. Add the huge difference in running costs, the fact that the homebuilts are new, and the impressive performance 2 up with bags and you have a very tempting proposition! I have transitioned from an AA5B with all the kit to an aircraft I have built myself and I would not go back. Second hand values for “plastic fantastic” aircraft are very strong right now and getting stronger. Sales of new “plastic fantastic” VLA / LSA aircraft are also booming and predicted to continue to grow very rapidly for the foreseeable future. Sales of older tec aircraft are in sharp decline, and second hand values are collapsing as the running costs start to be a significant % of the Hull value.
One small point which has been missed by the anti homebuild brigade. There are new rules coming in over the next few years which will allow a lot of the aircraft which are only available as home build in the UK to be factory built. In Europe for example, you can buy Dyn Aero aircraft factory built or as a kit. This has not been possible in the UK, but EASA will probably be changing this. Some of the designs will also be cleared for night and IFR.
Light weight Plastic aircraft are allegedly unsafe. All UK “Plastic Fantastics” have to comply with the modern CS-VLA design code. Many of the old 1950’s designs would not pass a modern design code and rely on “grandfather rights”. The survival cell tec now used is much less likely to land an engine in your lap than the good old designs of yester year.
Having said all that, if you have an IR and you want to use it then you have to stay, for the time being, with the old tec kit.
Rod1
As has been said, 99% of UK pilots are VFR only. Add the huge difference in running costs, the fact that the homebuilts are new, and the impressive performance 2 up with bags and you have a very tempting proposition! I have transitioned from an AA5B with all the kit to an aircraft I have built myself and I would not go back. Second hand values for “plastic fantastic” aircraft are very strong right now and getting stronger. Sales of new “plastic fantastic” VLA / LSA aircraft are also booming and predicted to continue to grow very rapidly for the foreseeable future. Sales of older tec aircraft are in sharp decline, and second hand values are collapsing as the running costs start to be a significant % of the Hull value.
One small point which has been missed by the anti homebuild brigade. There are new rules coming in over the next few years which will allow a lot of the aircraft which are only available as home build in the UK to be factory built. In Europe for example, you can buy Dyn Aero aircraft factory built or as a kit. This has not been possible in the UK, but EASA will probably be changing this. Some of the designs will also be cleared for night and IFR.
Light weight Plastic aircraft are allegedly unsafe. All UK “Plastic Fantastics” have to comply with the modern CS-VLA design code. Many of the old 1950’s designs would not pass a modern design code and rely on “grandfather rights”. The survival cell tec now used is much less likely to land an engine in your lap than the good old designs of yester year.
Having said all that, if you have an IR and you want to use it then you have to stay, for the time being, with the old tec kit.
Rod1
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Having said all that, if you have an IR and you want to use it then you have to stay, for the time being, with the old tec kit.
I have torn much hair out in the more southern bits of Europe when some ATCO (who fell out his bed on the wrong side) refused me a VFR transit. After the one before him let me through his bit and handed me over.
One generally plans OCAS when VFR but especially going East this often results in utterly torturous routes which dogleg all over the place and often place you in very unsafe places, like 1500ft above the Alps peaks (under Swiss FL130 Class C) which is OK if there is virtually zero wind, or at 1000ft above the sea off the coast of Italy under Class A with a 1000ft base, out of radio contact and with ~ 30 secs to ditching if the engine stops.
Ever wonder why people go halfway around the bend, learn the names of weather systems on Jupiter, how a 737 FMS works, all kinds of utter crap, to get that silly elitist piece of paper called an IR, and spend extra money flying a reasonably capable plane (like a TB20)?
Imagine a world in which CAS becomes irrelevant, as do danger areas, restricted areas, all the other VFR crap... where ATC take care of everything (actually most of the time they leave you alone) and you just FLY. On autopilot, taking pictures and making movies, eating strawberries at FL150. Every so often you call up the next unit, or select the next waypoint. In good weather you stop the initial climb and sit at FL100, otherwise you climb to stay VMC on top and ATC never practically refuses anything you ask for "due weather".
Weather permitting (as always) Europe suddenly becomes easy.
I know many pilots get a lot of fun doing local bimbles (and I do probably one a week myself because I like like flying around, drilling holes in clouds, etc) but if they want to go a bit further (somewhere where driving would be a right PITA) they face a whole mountain of crap.
Long trip VFR flight planning means covering the lounge floor with charts, stuck together with bits of tape, crawling over them drawing lines. And you have to plan two routes: the one you want (in CAS at times) and the backup one (100% OCAS).
I loved my long VFR flights (as far as the far end of Crete) but I am damn glad to never have to do them again because you never know when somebody will spring a little suprise at you. Why? Not because there is conflicting traffic but because he can! He can because you are "VFR" which means as far as he is concerned you have zero right to be there and you are in his airspace only because he or somebody else has been generous and let you in. Most airspace has no traffic at GA levels and it could be simply opened up to VFR, US-style, but this is not going to happen in Europe. ATCOs have their 3000 page book of rules and they will run that book for as long as they can. Most are great but you only need one to ruin your whole day. But if you were "IFR" on a Eurocontrol route he cannot touch you because you were cleared all the way on your first contact with ATC. All he can do is get you a little out of the way of actually conflicting traffic. It's a whole different mindset: Under IFR his job is to get you to where you are going. Under VFR he has no obligation to you whatsoever and his job is discharged by telling you to keep out of his airspace, and if this has created an unsafe situation that's not his problem ("you should have planned for it").
"Ultralights" are the future in pilot/airframe population numbers terms but they are also a near total dead end to any pretence of utility/travelling-A-to-B value.
It's true that today's IMCR-trained hacks will be just fine in marginal VFR and will be able to go places (like Rod1 here can I am sure) but give it some years and most of the pilots won't know what's hit them when they get into a cloud. I am sure 99% of pilots are VFR only but that 99% also has a massive churn rate, of the order of 1 year before packing it up for good. This can be sustained for only so long.
I am not giving up IFR until I have absolutely no option. It will have given me and my girlfriend the best trips to the best places, with the least hassle.
Last edited by IO540; 16th Jun 2008 at 16:44.
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Lots of IFR vs VFR comment there. But a teensy question.
Is there any logical reason (logical I said, not what the regulations say) why well designed well built plastic homebuilts with the necessary instrumentation should not be allowed to fly IFR?
Is there any logical reason (logical I said, not what the regulations say) why well designed well built plastic homebuilts with the necessary instrumentation should not be allowed to fly IFR?
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“Is there any logical reason (logical I said, not what the regulations say) why well designed well built plastic homebuilts with the necessary instrumentation should not be allowed to fly IFR?”
In The USA “our plastic fantastics” are flying in full IFR/IMC. I have practiced flying mine using fogles and an observer. It is a similar workload to flying a Pup on instruments and well within the limits of an IMCR pilot with some experience. My aircraft would not be suitable for serious IFR use in its current form as I only designed the panel and the backup systems to get me out of trouble, but it could be upgraded to a standard which would allow it to be flown in IFR/IMC if it was transported to the USA.
It is very probable that homebuilt aircraft will be allowed to fly IFR in Europe under new regs being drawn up, but the devil on this will be in the detail.
Rod1
In The USA “our plastic fantastics” are flying in full IFR/IMC. I have practiced flying mine using fogles and an observer. It is a similar workload to flying a Pup on instruments and well within the limits of an IMCR pilot with some experience. My aircraft would not be suitable for serious IFR use in its current form as I only designed the panel and the backup systems to get me out of trouble, but it could be upgraded to a standard which would allow it to be flown in IFR/IMC if it was transported to the USA.
It is very probable that homebuilt aircraft will be allowed to fly IFR in Europe under new regs being drawn up, but the devil on this will be in the detail.
Rod1
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SkyArrow 650
I wouldn't fly IFR in this [can't anyway] but it's carbon/kevlar, has bonding, and the best viz [VFR] for two in line seats at a reasonable price [if you build it yourself].
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Is there any logical reason (logical I said, not what the regulations say) why well designed well built plastic homebuilts with the necessary instrumentation should not be allowed to fly IFR?
The less charitable answer is that most are too flimsy to regularly fly in the turbulence which is routinely found in IMC. I know the theoretical design strength is still +3.8g or whatever, but next time you walk around some exhibition, do a 1 second comparison of the way different planes are built and you will be convinced
In the end it comes down to regulatory attitude to whether the State should determine the Individual's attitude to risk. Objectively it should NOT. You can climb rocks, scuba dive, etc. 3rd party risk in GA has been absolutely proved to be miniscule, and EASA recognised this in its published deliberations. But we are stuck with decades of the emotional legacy of a plane plummetting into somebody's head!
In the USA, Experimental Category planes can fly IFR if they obtain the appropriate signoff. I don't know the details but obviously they need to carry the legal equipment, and you don't see many £40k plastic jobs having a £10k IFR GPS installation. They have a £500 Garmin 296.
OK, one can legally fly IFR with a VOR etc and that is cheaper but we don't have a regulatory framework supporting enroute IFR without flying an instrument departure or approach (which should not be suprising since it would be silly) so IFR certification is going to mean carrying the whole IFR panel. Until GPS approaches etc etc etc are recognised in which case an IFR GPS might be legally sufficient.
It's anybody's guess what will happen.
But the subject of what and who (and what material "who" studied" to get their magic piece of paper) is by far the hardest emotional step to overcome, of all things in GA.
All the time you talk "just VFR" nothing is too hard. VFR stuff is by default kept OCAS and "therefore" doesn't affect any "real" planes (airlines). I can see EASA bringing in loads of welcome changes, on both airframes and licenses.
But the moment the dreaded 3-letter "I"-word is uttered, all the grey haired airline ex Training Captains with their six gold stripes, ceremonial swords and gold plated ATPLs come crawling out of the woodwork and together with their union reps and all the other assorted axe grinders they occupy every chair around the committee table.
Not saying it will never happen but it will take time before the really cheap machines can fly IFR. One possibility is that if EASA does introduce a grandfater to the UK IMCR, perhaps limited to some lower airspace, the low cost plastic planes might be able to fly IFR (i.e. in cloud) in that. That (keeping them out of the full IFR system) would be a plausible political solution.
It's tricky because if you allow a comprehensive Experiemental type system (like the USA) then you will have pressurised planes capable of FL300 and 350kt - look up the Epic Dynasty and Escape. These are flying as "homebuilts"!
Last edited by IO540; 17th Jun 2008 at 10:30.
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Are we confusing composite aircraft construction with, as you say, possibly flimsy aircraft designed to come in under arbitrary max gross weights established by the rulemakers?
Reason I ask is that designs like the Lancair series appear to have significantly better performance than your average metal or wood airframe because proper use has been made of the characteristics of composites (strength, stability of aerofoil shape and surface smoothness) in the design.
Reason I ask is that designs like the Lancair series appear to have significantly better performance than your average metal or wood airframe because proper use has been made of the characteristics of composites (strength, stability of aerofoil shape and surface smoothness) in the design.
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As I pointed out above, any UK Plastic fantastic will have passed CS-VLA and is not going to fold up at the first sign of turbulence. I am sure that they look a lot less substantial than a metal aircraft designed in the 50’s, but a modern carbon spar is a lot less likely to cause problems than a metal one, particularly a 40 year old metal one. Remember, the design factor for composite aircraft is 2, on a metal aircraft it is only 1.5. In flight break-ups of LAA approved aircraft are so rare as to be insignificant.
Your Lancair example is hardly surprising when you consider that the 172 was designed in the early 1950’s. Carbon fiber did not exist back then and we have learned a lot about aerodynamics. Composites lend themselves to being molded in much more complex shapes then metal, particularly metal which is being mass produced down to a price. A VANS will also give vastly better performance than a 172 on the same engine. This is metal v metal which goes to show how light aircraft design has moved on.
Rod1
Your Lancair example is hardly surprising when you consider that the 172 was designed in the early 1950’s. Carbon fiber did not exist back then and we have learned a lot about aerodynamics. Composites lend themselves to being molded in much more complex shapes then metal, particularly metal which is being mass produced down to a price. A VANS will also give vastly better performance than a 172 on the same engine. This is metal v metal which goes to show how light aircraft design has moved on.
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Reason I ask is that designs like the Lancair series appear to have significantly better performance than your average metal or wood airframe because proper use has been made of the characteristics of composites (strength, stability of aerofoil shape and surface smoothness) in the design.
When designing experimentals you can cut corners in ways that you couldn't get away with in a certified aircraft. All fine and fair enough, but one should keep that in mind when evaluating the relative merits of different aircraft... Such perfectly legal non-compliance is the one reason why I would never do any significant amount of flying in a non-CofA aircraft. A few flights now and then tho'...
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Join Date: Feb 2002
Location: Inverness-shire
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But wing struts? Hardly cutting edge design. Last glider I saw with them was a T21 built in 1950.
Is that really the best aerodynamics the Jab designers could do or are they (admittedly effective) cunning weight saving devices to meet daft max gross weight regulations?
Or dare one say it, people are happier if it looks a bit like a Cessna?
But efficient aerodynamics? Doubtful
Is that really the best aerodynamics the Jab designers could do or are they (admittedly effective) cunning weight saving devices to meet daft max gross weight regulations?
Or dare one say it, people are happier if it looks a bit like a Cessna?
But efficient aerodynamics? Doubtful
Join Date: Apr 2003
Location: Midlands
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Have a look at;
http://www.laaeastmidlands.org/GKARK.html
It will give you an idea about the structure.
“But wing struts? Hardly cutting edge design.”
No wing struts on this one!
Rod1
http://www.laaeastmidlands.org/GKARK.html
It will give you an idea about the structure.
“But wing struts? Hardly cutting edge design.”
No wing struts on this one!
Rod1
