Aces High Bulletin Board
General Forums => The O' Club => Topic started by: Chairboy on January 27, 2006, 04:39:28 PM
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As some of you may remember, a couple months ago I began thinking hard about building my own plane again. Well, in the past few weeks, I decided to just do it.
I've placed my initial order for supplies and plans to build a Cozy Mk IV, a composite canard aircraft that's based on the Burt Rutan LongEZ (it actually has his blessing).
I've faxed in my license agreement and have spent $1400 on foam, fiberglass, epoxy, a ratio pump, plans and other miscellaneous things needed to start the bulkhead chapter.
I plan to power it with a Mazda rotary engine which will be turbo normalized. I'm considering using an IVO in-flight electric adjustable prop configured to be a constant speed prop, and estimate it will take approximately 2,700 hours to build.
Here's the webpage I've started to document my progress, including some early thoughts on panel design (it'll be hopelessly out of date by the time I need to buy avionics, but it's still fun to dream) and the modifications I plan to make.
http://hallert.net/cozy/
Since the paint scheme is the most important thing to determine before actual construction begins, here's an image from http://hallert.net/cozy/paintideas.htm:
(http://hallert.net/cozy/images/cozyside.gif)
Ok, let the beatings begin. To help keep things organized, I've anticipated the following main areas of criticism. Label your post appropriately. :D
* Rotary? Are you stupid?
* Composite? Why not an Vans RV aluminum plane, you commie?
* ROTARY?!
* Your paint scheme is going to melt your airplane, don't you know anything about Tg?
* Well, have you considered a Lycoming instead?
* Modifications? Ha ha ha ha, you gonna die boy.
I'm sure there are more, these are just the biggies.
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Cool Chair. unless of course you actually fly the thing.
:O
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Hispano's or .50's?
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Originally posted by midnight Target
Cool Chair. unless of course you actually fly the thing.
:O
:rofl
Good luck Ben! I've always wanted to do that, still may, but I'm waiting on retirement.
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I thought you had just lost your job? Or has new employment come thru?
Rotary....eh...good for cars...airplanes...well...I havent heard a lot of great things. I'd stick with something more known (Avo-Lycoming, etc)
Canards are pretty...you dont see em a lot. Im kinda undecided if Id ever want one or not. For every bad thing I hear, I hear and equal amount of good, so its a wash.
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nothing wrong with Rotary engines .
Good points
they have the ability to run at very high rpms without major damage 12,000-15,000 rpm .
they make decient Torque at 5000 +
I remember they go more hrs vs a piston eng befor a major overhaul
(I'm not shure on the hourly amount )
possiable bad points
they need a very good oil cooling system
The exhaust when ran with just a header is EXTREAMLY HOT and produces alot more heat then a piston eng.
You will have to intercool the turbo also.
More later as i remember from my ole "Rotory drag racing days"
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Whoa this turbine powered one (http://bluemountainavionics.com/greg/aircraft.html) looks mighty cool....
(http://bluemountainavionics.com/greg/Cozyjet%20over%20Lake.jpg)
The guy who designed the Mark 4 also started out with a BD-5 years ago. Great read (http://www.cozyaircraft.com/nats.html)
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A few years back, the subaru engine mods were all the rage...
Cozy is a nice model. A bit porky in my opinion, but that means roomy inside and it's still a very efficient design. Not a good plane for acro, but it sounds like you're going for cruise efficiency and trips over local fun-flights anyhow.
I've always wondered how they'd do with a nice turboprop... Nasa sponsored a bunch of small turbine designs to help spur the introduction of turbine tech down towards private aircraft owners, but so far they've only made it into the VLJ business market.
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I'm not real sure about the engine choice.
Were it me, I'd do a big bore (94mm VW bug jugs and Rabbit rods) Corvair with a small turbo and budget EFI based on a GM engine management system. The Corvair engine is VERY popular with the home builders, and the Corvair hot rodders have done a real good job developing the stuff needed. Provided you duct enough air to cool it and use an adequate oil cooler, you'll have plenty of power, reliability and simplicity.
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“You’ll shoot your eye out with that thing!”
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Originally posted by LePaul
The guy who designed the Mark 4 also started out with a BD-5 years ago.
Burt Rutan was on the original BD-5 design team.
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Originally posted by LePaul
I thought you had just lost your job? Or has new employment come thru?
Still unemployed, but I got my severance check, wife is working, so... I figured that I'd work on my project while looking for a job. Better than sitting on the computer. Compared to a Vans RV, the initial cost is pretty low to get started.
Originally posted by LePaul
Rotary....eh...good for cars...airplanes...well...I havent heard a lot of great things. I'd stick with something more known (Avo-Lycoming, etc)
There are plenty of gravestones out there associated with Lycoming. They aren't anything special when it comes to reliability, their only 'virtue' is that the degree of how unreliable they are is well documented. Just about every pilot I know with a few thousand hours has had at least one engine failure, usually more.
Rotaries are unproven as of yet, but 26 moving parts versus 3 moving parts... that's a step in the right direction if I heard of one. There are plenty of 'em flying, some of them over a thousand hours. The reliability info is being established.
Originally posted by LePaul
Canards are pretty...you dont see em a lot. Im kinda undecided if Id ever want one or not. For every bad thing I hear, I hear and equal amount of good, so its a wash.
I really like a few things about canards:
Stall resistance: The canard stalls before the main wing, so it's wicked hard to get it into a spin, and if you sit there at idle with the stick pulled all the way back, the nose will just bob up and down gently as the plane descends.
Efficiency: Unlike a conventional setup, both lifting surfaces produce lift. The tail of a normal plane produces downforce, which increases the energy/fuel needs and slows the plane down.
Sexiness: It looks like a space ship, and that's what I want. Heck, check out the paint job. :D
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Originally posted by Vulcan
Hispano's or .50's?
I'm gonna troll the military yards to see about standardized hardpoints that I can use for the baggage pods. If I happen to be able to mount a stock .50 cal gunpod from the same point and there happens to be a lead to it that's triggered from the cockpit, well....
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Originally posted by Captain Virgil Hilts
I'm not real sure about the engine choice.
Were it me, I'd do a big bore (94mm VW bug jugs and Rabbit rods) Corvair with a small turbo and budget EFI based on a GM engine management system. The Corvair engine is VERY popular with the home builders, and the Corvair hot rodders have done a real good job developing the stuff needed. Provided you duct enough air to cool it and use an adequate oil cooler, you'll have plenty of power, reliability and simplicity.
I'm not a big fan of piston engines, too many moving parts that fail catastrophically. If I was going to stick with auto conversions and not do a rotary, I'd be more likely to use a Subaru. It's the right mix of power and reliability and there are a LOT of them flying.
It's amazing how well the VW engines do, the Sonerai does 200mph on one of those.
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for some reason the idea of building (And flying) a homemade aircraft reminds me of one of the lines from Serenity (the landing scene just after credits)
pilot "this should be interesting"
captain "define 'interesting'. "
pilot "oh God. oh God. we're all gonna die."
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IMHO if its rotary powered, it should be a Le Rhone.
Theres used to be an EAA Nieuport squadron based either at KSLE or Independence, maybe they can help with that.
Also, you should grow a bigger moustache
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Originally posted by Debonair
IMHO if its rotary powered, it should be a Le Rhone.
Theres used to be an EAA Nieuport squadron based either at KSLE or Independence, maybe they can help with that.
Also, you should grow a bigger moustache
Heh, different type of rotary. I'm using a WANKEL.
:D
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Originally posted by Chairboy
...I'm using a WANKEL.
:D
I don't care what you do in the privacy of your home...
...Clerget powered swept wing canard would be a great mix of space age & horse and buggy days, like in the 80's when my grandfather bought a Taurus...
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i ran a 13b wankel "Mazda" in a datsun 510 2door with an auto behind it and 4.33 to 1 gears i used a motorcraft 4 bbl carb set up 1 to 1 likea mini domanator and a 2 1/2 primary tube header ith 3 1/2 in collector then thru a super trap muffler ... this thing ran 11.90 in the 1/4 mile and would rev to 14,000 rpm .
this was one of the 30.000 mile Japan recycle engines basically untouched on the insides .. and the guy i sold it to raced it for 5 seasons and put well over 120,000 on it befor it started smoking real bad .. it never broke .
This motor went thru hell .. so thats what my rotory experiance is .
but theres nothing wrong with those Suburu engines either.
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Rand Cam (http://www.regtech.com/) Diesel would be the ultimate engine for you, if it ever gets into serial production.
http://www.regtech.com/16.html
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There are plenty of gravestones out there associated with Lycoming. They aren't anything special when it comes to reliability, their only 'virtue' is that the degree of how unreliable they are is well documented.
I think you are misleading yourself. If you look at the shear number of Lycs out there of course you are going to have failures. I'd like to see total numbers of engines ever built and flown against number of failures.
I liked the link you had for the rotary stuff. They looked cool. I drive a 94 RX7 and love it. It is a gass guzzler when I got the twin turbos working and it is like driving a Bike performance wise.
IMO ok so you have less moving parts in the engine iteself, but you are also adding a cooling system, which if you have the slightest of problems you are in trouble. Then you have the gear drive assembly so are you really cutting down on moving parts and simplifying systems???
Personally, if I am going to put my family and friends in something I built I would want the engine to have a long history of proven service much like the lycs rather than just looking good on paper.
Sounds like fun, good luck
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When the engine takes a dump on you...are you going to say "well at least I saved money putting it in the airplane I and my family are in now!"
With the Lycoming...it's very likely you'll never have to say such things because an O-320/O-360 is as bulletproof a motor as you can find. They're not good at being quiet when you want them to make noise.
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The Lycoming mafia strikes again... :D
This isn't about saving money, it's about not trusting my life and the life of my family to a Lycosaurus, 1930's technology that's been worshipped as infallible because if it costs $15,000 to overhaul, it's GOTTA be good.
Lycomings and Continental are old, inefficient, and fragile. They're prone to shock cooling, burnt valves, thrown rods, and they come apart all the time. Getting one to TBO is a chore, they vibrate like you're being towed through the air by a herd of elephants, and when they fail, they fail catastrophically.
A rotary might not be perfect, but when it fails, it usually continues to generate reduced power (making it easier to get to a landing spot). Just about all engine outs on rotary powered planes have been accessories, not the engine itself. There are hundreds of people developing the solid rotary setup, and I have years before I buy a powerplant to watch and learn.
The only advantage a Lycoming gives me is that it's easier to just bolt on and fly, but I'm not satisfied with the level of reliability, failure modes, or design of the engine, so I'm adding a bunch of time to do an engine test regime with a rotary.
Something to think about, there are more hours on wankel rotary engines than there are on Lycomings, and they are produced on a much larger scale and are constantly being improved. It's a proven engine, just not proven on aircraft yet.
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Good luck on your project! Sounds like a fun ride.
I agree with you on Lycoming technology. It is ancient and obsolete.
The O235 L2C, O320 and O360 parrallel valve models however are extremely reliable and routinely reach TBO. I think you are overstating their weaknesses.
The fact that "Its a proven engine, just not proven on aircraft yet." means that it is unproven in your anticipated application. The problem with any automotive adaptation to this point is that the old creaky Lyc is designed to operate at and routinely operates at up to 75% of rated power and most automotive engines are not and do not.
You might turn out to be correct. It might be the smoothest and most reliable setup since the P&W PT6 series. If it were my airplane and family though I'd stick with the devil I know instead of the devil I don't.
You say the only advantage to a Lycoming is ease of installation. I can think of two more: A constant speed prop (which would be way nice), and probably better resale value if it ever winds up in Trade-A Plane.
I wish you great luck with this project and the conversion.
Don (Casca) Corleone
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You can install a CS prop on a rotary, and I'm considering one. If I do, I'll propably use an electric instead of hydraulic CS prop, it depends on the state of the industry when I get there.
As for resale, I'm building the plane for ME, not for the next guy who might own it. :D A plane like this could be something I own for the rest of my life (I know that opens up some great joke opportunities, heh). I doubt the decrease in resale would be the entire amount of the engine, but if so, meh. Like I said, I don't like Lycomings.
Another nice thing about the Rotary: I can rebuild it myself in a couple hours with a $1.99 socket set. It's simple, bulletproof, and easy to work on. Who could ask for anything more?
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That turboprop article was a good read, I wonder what kind of economy he's getting
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Lycoming motors may be 1930's technology...but they work.
My post a few posts up and Casca mention the O320, O360 and O235 as found on the C-152.
These motors are as bullet proof as they come and the only ones that I've ever seen not make TBO are ones not maintained with regular oil changes at the 50 hr mark (or 90 days).
Looking at engine trouble I've blown a cylinder on an O-200 (continental) in a C-150.
I've had a rough running O-320 whicih turned out to be a bad set of piston rings from the overhaul (non factory) at less than 20 hrs after the engine change.
O-320 oil return line clamp was loose resulting in oil contacting hot engine parts making some smoke. Shut down motor and returned to land. A few turns of a hose clamp socket later the airplane was good to go.
That's a pretty short list for 1400 hours of Lycoming time in many different makes/models of varying maint. status.
The O-200 in the 150 was used/abused flight school airplane worked too hard.
The piston rings hang squarely on the shop.
The oil return hose is no big deal.
As far as Who could ask for anything more?
I'll fly my family behind proven technology. If there was something that much better...wouldn't they be using it? It's old...but proven.
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Originally posted by Golfer
If there was something that much better...wouldn't they be using it?
Bestest argument evar. I'll call up the patent office, won't be needing them anymore! While I'm doing that, you can get on the phone to the companies with R&D organizations with the good news that they can all close up shop.
On a more serious note, aircraft piston engine development basically stopped after the introduction of the turbine. The piston GA market is too small to fund technology improvements, and the military dollars went towards jets. Automotive engine development has continued because there's so much money in it, but there just isn't enough demand for anywhere near the same level of research for small planes.
Compare the quality requirements for modern auto engines against 'factory new specs' for a Lycoming someday. You'll be convinced that someone misplaced a decimal point... but they didn't.
The rotary isn't proven in small planes yet, but there are a few million of them out there in cars and other areas, and they're doing fine and getting better every day. The last time the Lycoming got better, we were in the middle of the New Deal. :D
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Don't a lot of ultralights have small rotary engines in them?
As for myself, dad had 2 snowmobiles same model, 1 had 15 hp piston engine.
Other had 15 hp rotary engine.
None of us kids could start the piston job, but we could all easily start the other one.
So guess which one we beat the living crap out of?
It never did die, got so it smoked a bit more, drank a bit more oil. But it never did die.
Dad used the other one for fishing for years. Pulled amazingly large fishing houses through 3 ' unbroken snow, that crazy snocat thought it was a bulldozer. Right up till the day it blew.
Stick to your guns & good luck chair!
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don't rotary engines get weird torque issues with the engine working like a make-shift gyroscope when you try to maneuver?
seems like I heard something about it on WW1 planes. maybe newer engines don't have the same problem.
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Chairboy is talking about a Wankel Rotary engine:
http://auto.howstuffworks.com/rotary-engine7.htm
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Originally posted by Chairboy
Wow a history, economics and aviation lesson all in one.
I won't compare specs because there really isn't a need. The little Pitts in the hangar is going to have an O-360 with a good deal of personal touch. I ever build an RV it's going to have a straight IO-360. These motors don't "just break" and they're not a catastrophe waiting to happen. If they caused that many troubles (the 4 cylinder Lycomings...nothing with six or a turbo) why would someone fork over $200,000 for a 172 to fly 120kts behind a ticking timebomb?
When did you get so afriad of simple engines anyway? Been hanging around a few EAA wingnuts it seems. If they tell you next that a 172 is a dangerous airplane...they're fibbing.
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I wonder why people insist on using ancient technology. Maybe they are the ones afraid and not vice versa?
Not that Wankel is anything new, but it's small, light, simple and reliable, and reasonably fuel efficient. Those are exactly the qualities of a good aero engine.
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I'll fly my family behind proven technology. If there was something that much better...wouldn't they be using it? It's old...but proven.
Chair, you seem to be caught by emotion and what looks good on paper rather than tried and tested.
While I agree no company is going to spend the time and money to certify new technology, I disagree that Lycs are 1930s technology and that is why they are a bad choice. Do you know how old the Wenkle technology is. Lycs have evolved just like everything else.
Again you should look at the numbers of lycs out there performing every day compared to number of failures to get some perspective.
If you were talking about Continentals I would whole heartedly agree with you, but the Lycs are good motors and proven.
I hope the Rotary does work. It definately looks great on paper. I would not put much stock in the "Its works great in a car" logic. They are two totally different animals and the logic does not work.
I have an email in to the site you linked to to find out if anyone is using the Wenkel for aerobatics. I am thinking of building an Edge 540 or Pitts S11B and like I said the Wenk looks good on paper and I like the idea of an easy rebuild.
But then I get to thinking... After investing all that money and time into the plane, would I really want to roll the dice and take the chance of being the guy that hits the 1 big snag? Food for thought, not because I swear by Lycs, but because they are proven and you rarely get a second chance once you are wheels up.
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Originally posted by Golfer
When did you get so afriad of simple engines anyway? Been hanging around a few EAA wingnuts it seems. If they tell you next that a 172 is a dangerous airplane...they're fibbing.
The EAA is full of Lycoming/Continental/Franklin/etc fans. This is from an evaluation that uses basic risk assessment techniques. I think there's a bit of unwarranted fawning over those aircraft engines that's a bit unusual. No need to get riled up about it, and I'm not afraid of Virginia Wolf or these certified engines, I just think that there's something better and I'm willing to put my money where my mouth is. :D
After all, it's an experimental aircraft, right? The purpose of experimentation is to prove/disprove theories, and my theory is that Rotary's are better suited for my purpose than a Lycoming.
Time will tell, and I'll be sure to report back with my progress.
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Originally posted by mars01
Chair, you seem to be caught by emotion and what looks good on paper rather than tried and tested.
With respect, I think that the emotion is on the side of the Lycoming fans. I'm just trying to make a straight-forward assessment of the technology based on past performance, size of industrial base, status of improvement, and so on.
Originally posted by mars01
But then I get to thinking... After investing all that money and time into the plane, would I really want to roll the dice and take the chance of being the guy that hits the 1 big snag? Food for thought, not because I swear by Lycs, but because they are proven and you rarely get a second chance once you are wheel up.
Fair enough, but you face the exact same question with the Lycomings. They aren't failsafe, they DO break, and thousands and thousands of people have died because of those breakages.
Tain' nothing mystical about the Lycoming, it's just a straight-forward, well engineered engine. There's a reason it's been around this long, aside from the economics of engine development which Golfer made fun of, and that's that it's a good, known quantity. My position is that the Rotary seems like it might be even better (and I KNOW it's smoother), so I'm going to use it instead.
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Originally posted by mora
Chairboy is talking about a Wankel Rotary engine:
http://auto.howstuffworks.com/rotary-engine7.htm
thanks, that makes much more sense. I've never seen how one works before.
never could get my mind around some variant of this-
(http://www.wwiaviation.com/photos/engines/gnome-9.jpg)
in a car.
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Capt Apathy: But how about a motorcycle? Cue the Harley Davidson, an aircraft engine missing 8 cylinders. :D
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lol.
IIRC, in the Camel that whole mess spun around the crank shaft. right?
I was picturing that in the little plane of yours. it wasn't pretty.
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Originally posted by Roscoroo
You will have to intercool the turbo also.
unless he is going to use a supercharger or put another turbo on its an aftercooler.
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I plan to intercool the turbo, heat kills components, and I want this to be bulletproof. Variations of P-51 style scoops are being tried with good results as alternatives to the NACA scoop, but we'll see how it develops.
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an intercooler is used when the charge air is going to be compressed again using a supercharger or another turbo. an aftercooler is used when the charge air is compressed only once. cooling the turbo is well cooling the turbo. i have a Caterpillar C-16 (just short of 1000 cubic inches) rated at 800hp @ 1800 rpm (1050 hp on nitrous for 15 seconds) and cool the turbo with engine oil which is cooled by an extened range oil cooler using engine coolant at an aveage temp of 185 deg. but then i'm not an aircraft mechanic and you guys may use different terms.
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Originally posted by JTs
an intercooler is used when the charge air is going to be compressed again using a supercharger or another turbo. an aftercooler is used when the charge air is compressed only once. cooling the turbo is well cooling the turbo. i have a Caterpillar C-16 (just short of 1000 cubic inches) rated at 800hp @ 1800 rpm (1050 hp on nitrous for 15 seconds) and cool the turbo with engine oil which is cooled by an extened range oil cooler using engine coolant at an aveage temp of 185 deg. but then i'm not an aircraft mechanic and you guys may use different terms.
I have a 760 turbo Volvo with an inter-cooled turbo.
it's just one turbo, no supercharger either.
the turbocharger is cooled internally with engine coolant, and lubricated with engine oil.
inter-cooled (cooled inside I'd suppose) turbo's last much longer. I've got over a 1/4 million miles on the original turbo charger.
edit- IIRC the turbo is made by Mitsubishi
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Originally posted by Golfer
As far as I'll fly my family behind proven technology. If there was something that much better...wouldn't they be using it? It's old...but proven.
When flying a cozy, hopefully you won't be behind the engine technology.
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Heh, great point. If your family is behind the engine while flying in a Cozy, something has gone terribly wrong indeed.
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You know if anyone in here has the determination and tenacity to finish a project of this magnitude it is Chairboy.
Good luck and keep us posted on the progress.
Have you looked at that new engine Rotax is developing? They have thousands of aircraft engines on homebuilts and ultralights. My 912S is really a nice well performing engine. I think the new engine will be out in time for your project.
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Hey Chairboy, have you taken your obligatory trips to Redmond and Cottage Grove yet?
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I've flown over Cottage Grove airport, what's there? And what's in Redmond, Vans?
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Lancair kits in Redmond, production aircraft in Bend.
Cottage Grove is where the guy that built the replica Bee Gee is from. He also built (and augered it in) the replica Hughes H1. He's gone, but hopefully the group of homebuilders in his group still carry on.
In Roseburg was a couple who "Winnebagoed" a Grumman Albatross and flew the pacific rim. I haven't heard what they are up to lately.
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Chairboy here is the link to the new Rotax engines.
Rotax Engines (http://www.brp.com/en-CA/Innovation/Technology/V220.V300T.Aircraft.Engines.htm)
The US distributor site (lots more information) (http://www.vaircraftengines.com/home.asp)
You should really consider these instead of a rotary engine. Because they are Rotax they will become the standard for homebuilt and you can rely on Rotax for parts and service.
Rotax has such a long history with its 912 line of engines in homebuilt aircraft that I would expect their new engines to be very well designed. The advanced engine controls will insure the engine runs at optimium conditions at all time. They will be out in time for your project and since you will not need one for a couple of years they will already have track record by the time you buy one.
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I'll keep an eye on the Rotax, of course, but I dunno. We'll see, I know that they're becoming popular, along with the Jabiru, but I'm not sure they've got a lot of engines running in the horsepower range I'm interested in. There are a couple million Wankel rotary engines in that power range, and about 300,000 Lycomings, for comparison.
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Those two engines put out 220 hp and 300 hp respectively.
How much HP are you looking for?
There are millions and millions of Rotax engines in the market. Most are in snowmobiles and boats etc. However the 912 series is widely used in the ultralight, sport pilot and homebuilt fields. Many are used in certified aircraft.
Rotax is the industry standard for 60 to 100 HP engines. Now they are moving up into the bigger plane market with those two engines. I would say that you would be smart to seriously consider them when you are ready to buy.
Also never buy your engine until the last possible second. Many homebuilders buy a year or two before they need them and frequently find when they go to use them that there are AD's on their older engines or changes in the newer ones.
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180-220hp is my target. The second to last thing I'm buying is the engine, and the last thing I'm buying is the avionics. :D
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for those on a tight bugget,here's a plane we all can build
http://www.funnyjunk.com/funny_pictures/460/Build+Your+Own+Airplane (http://www.funnyjunk.com/funny_pictures/460/Build+Your+Own+Airplane) :aok
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Sure, but the weight and balance is a bugger.