baco

Hi friends, finally begin Eole Construction, based upon Fillon´s peanut size free flight. First Thing was to make longerons for wings, each is pine hard wood softened with ammonia.
All wing´s construction is made over an specifically designed construction jig....
Fuse is more conventional, but very little in size. Just enough to put 2 S133 futaba servos, receiver and a 300 mA battery pack. Photos in a near future.

Happy new year to everybody !

MR Flyer57

Great to hear of a new plane getting started! Can't wait to see the pictures.
MR Flyer57

DICKEYBIRD

Is this it? WOW! Is that cool or what! http://www.fiddlersgreen.net/aircraf.../eole/eole.htm

baco

Yeah ..it is !

But with a .051 Cox engine, and near a meter of wingspan. Plan were CAD designed by myself. Wing is modified to give it self-stability, as in any flying wing, tips have important washout.
Today I´m building jigs for wing´s construction....

MR Flyer57

OH man!!!
Hey Baco are you involved in the 1/2A design and build competition we are having here on this site.
That is just what I think this should be about. Love the strange and new/old designs.
Keep us posted on the way!!

That looks like one of the "Magnificent men in their flying machines" planes. I was so jacked up by the film, that I can trace most of the enthusiasm I had as a boy to that one movie.
I believe it was the first time I truly convinced myself that even I could build that stuff.
MR Flyer57

baco

Yeah Mr Flyer57....it seems to be from "those magnificent..." but really it¨s OLDER. The real thing did ??? a hop in 1890. It was powered by a steam engine, and may be the first heavy than air thing to hop-fly.
Also this model is now included in design conquest.
Also have uploaded copy of original Fillon´s plans file.


Regards
Daniel

baco

Wings longerons and leading edge are just finshed...it took long time let them dry. So this weekend may be both wing halves are ready to cover.
Also hope can post some photos of construction .

BMatthews

I hate to suggest this at the point in construction that you've gotten to but "almost a meter in span" is not very large for a model of this type to be powered by an 051. It may LOOK like an Eole but it's going to fly like a Mustang! If you're following the PNut style construction, as it sounds like you're doing, I'm sure the ready to fly weight is going to be low. Combine that with not much drag thanks to a small'ish airframe for this much power and it's very likely the power will cause the airframe to distort at speed and result in an unfortunate outcome.

I refer to the fact that 1/2A old timer Texaco event models are flying very much like your model SHOULD fly with around 300 sq inches of wing area and a weight of 19 oz. The speed of those models is only held in check by using grossly oversized props on the engines, typically 8x5's. Even on these models changing back to the usual 6x3 turns them into little demons.

If you had the option or desire to build another one I'd consider upping the TOTAL wing area to about 400 to 450 sq inches. This number would take into consideration the usual plank style flying wing EFFECTIVE area calculations where the rear third of the wing is to add stability. And the Eole IS actually a plank style. The leading edge sweep back being matched by trailing edge sweep forward. There is a little bit of aerodynamic sweep there but not a lot. Most of the stabilization is obviously coming from the highly reflexed center rear of the wing.

Now how to deal with your current model? I'd consider a change to a reed valved engine. A Baby Bee with a 7x4 or 7x3 or even up to 8x4 or 8x5's would easily provide ample power for proper Eole style flying I would suspect. You can TRY a large prop on the 051 but these engines were ported for high rpms and may not respond well to being lugged down by big props. Another option if you're commited to the 051 would be to use as large a prop as it's happy with and then add an exhaust restrictor to the cylinder as a ground fixed throttle.

And finally there is the sound. The big props on the reed engines tone the shreik down to a 4 stroke like sound that would fit the nature of the Eole much better IMHO.

This really is a great project and I wish you all the best of luck with it. I'll be looking forward to hearing about and seeing the successful outcome.

combatpigg

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HI BACO! You sure picked an interesting one to do! Any chance of trying to hand craft a scale type prop too? Bruce's idea about scaling it up a bit should make it a more majestic and elegant flyer, and not add much weight. I didn't know a COX reed engine could tolerate swinging an 8" prop though! The original designer must have been quite the MAD SCIENTIST type! This will be an interesting project to follow.

MR Flyer57

After reading BMatthews thoughts on the plane, I have to agree.

I think you may have put a rocket motor on this plane.
Many of the planes of that era had very limited speed envelopes, and when modeled they can be easily taken beyond the models comfort zone and into an area where everything starts flapping.

I have done this on power gliders and it is easy to do on old time designs.

You may have to figure this into your stats for the plane, and might even think about dropping to a .020 size engine.

If you can come up with a throttle sleeve for the .051 or .049 your thinking of using it might be a good idea to use it.

This would be a great plane to use a Dickybird motor on, and though I am certainly no expert, I would hedge my bet and use only enough power to fly the plane on my first flights.

Just a little static from the peanut gallery,
MR Flyer57

Bipe Flyer

How about a little steam engine to make it more scale?

baco

Yeah BMatthews, your thinking are ok, but I did a mistake when I´had posted near a meter wingspan...really it´s a 1.2 (47 inch) meter wingspan. This make a bigger model.
But when the thing grows....I become to think to use my old 0.049, and making it even easier to construct, simplyfing it nose also, and not overpowered ! I don´t wish to have a bat with a roket on its tail !
Also I must said here we are near 3000 ft over sea level, and 0.049 are a little lazy with 5% nitro (great!) .
Wing construction is like peanut, but all is hard (pine) wood using some fiberglass/epoxi at critical points.

Daniel

BMatthews

Oh well then. You're in fine shape. It'll still be overpowered if you run the 051 on a 6x3. DO consider using at least a 7x3 or 7x4 to keep it in hand. I remember now that a buddy of mine flies an Etrich Taube free flight scaler on a TeeDee 049 with a Cox 7x3 1/2 and it runs at about 9000 rpm so that would be an excellent point to start with . His Taube is in the same size range as your Eole and weighs in at 16 oz. The 049 with that prop offers a very nice scale climb but then the Taube is a laundry yard of rigging so there's LOTS of drag.

Please post pics of your progress. This promises to be a very interesting and intruiging project. I suspect we can all learn a lot from your construction methods.

BMatthews

The engines used in the 1/2A Texaco old timer event did more than that. In their quest for fuel run economy they were running 10x4's, 5% nitro fuel and about 4 head gaskets. The flight of these models was basically a slow uphill glide and the run times were close to 13 minutes in the right conditions. This sort of made the 15 minute max flight a bit of a joke. They then cut the max diameter down to 8 inches and a couple of years later ruled out the larger 8cc tank in favour of the Baby Bee 5cc tank to further restrict the engine run times.

I typically run a thinned down and undercambered wood 8x5 cut down from a Zinger 9x5 and get 4 minute to 4.5 minute runs on the 5 cc. If it's cold the engine uses more fuel and my runs go down to about 3.5 minutes. I've done better when using a similarly made up 8x6 but the climb on my model suffers and if it's windy and turbulent I have a hard time punching through the rough stuff to get a good height where I can look for thermals. If it's REALLY rough I go back to a narrow 8x4.

Bipe Flyer

Am I right in thinking that reed valve engines are for all intents and purposes "zero timed" regardless of RPM and therefore able to tolerate a large range of prop sizes at the cost of not being optimized for a particular prop/RPM combo?

I've run a 5X3 on a PeeWee with no ill effects while gaining run time and reducing noise. Do you think it would be capable of running a 6X2 without causing damage?

MR Flyer57

I would think that they would get hot, trying to run such a large prop. To get them to turn, wouldn't you have to lean them out quit a bit?
I was looking at the Texaco head, and I can see the quest for cooling.
Also I always thought that you could control the timing by the amount of nitro as well as the amount of compression, but there must be a heat factor that I am not accounting for.

I have also come across shims that go under the barrel, and that must be used for changing the port timing. There must be a science to this that is hard and fast but I don't know it.

The magic that can be worked into the mix seems unlimited, and all I can remember is not being able to get the little guys to fire up when the other kids were watching!!!

It seems that if I try to run a larger prop and not let the cox engines spin up, they don't produce any power. I get more power at 18,000 with a small prop than 13,000 with a larger one, or in the extreme 9,000 with a very large prop.

I can't imagine what a Texaco event would have been like.

MR Flyer57

Bipe Flyer

I guess it depends on how you define power. HP, torque or thrust.

buzzard bait

Many people run Pee Wees on 6x3s. In fact those engines have even been run on the old Tornado 7x2! I have tried the 6x3 on the test stand with a remote fuel tank using a pretty long fuel line. I got a very odd, very regular, periodic cycling from about 10,000 to 8,000, back and forth. I'll try adding a couple of head gaskets, but I must say that the cylinder did not get especially hot. Maybe the long fuel line is my problem. A 6x2 sounds like a good idea. Jim

BMatthews

There's no doubt that if you wnat pure thrust then sizing the prop to operate the engine at it's peak horsepower RPM is the way to go. From there you play with props to find the most pull for your intended style of flying while letting the engine stay at it's peak power RPM. Hence the reason why free flight power models use relatively larger diameter and finer pitch props compared to CL speed models with their little high pitched tootpicks.

For 049's this means a max diameter of 6 inches or less. Trying to operate them with larger props limits the rpms and should only be done to maximize other parameters like fuel efficiency or noise reduction and shaping. The Texaco style of engine use sure SOUNDS nice in a large rubber model like scale classic looking model but there's no way it's producing max power OR thrust.

I think it's more accurate to describe reedies as variable timed rather than zero timed. Since they react to pure pressure differentials the open and close timings will vary with RPMs and the mass inertia of the fuel-air mixture in the system.

When the engines are loaded up with large props they SHOULD run hotter but this can be controlled by using lower nitro or modifying the compression ratio by adding head gaskets. I think Cox came up with the Texaco glow head more for the folks that don't know they were suppposed to use low nitro and extra head shims with that engine. The old "we had to protect you from yourself" syndrome at work. Used with 5 % nitro I've operated my regular Black Widow in two models and at least a hundred flights over about 15 years with the same glow head. A standard hemispherical one. Well OK. I may have replaced it once due to the platinum wearing off with age it but it's never overheated or blown from the "abuse". And that includes a fair number of runs where it went lean in the air.

The PeeWee will run fine with a 6 inch prop but there's no doubt that it's below it's peak power rpm with those. I think the grey 020 competition prop was a 5x2.5? Certainly it had a narrower blade than the 6 inch or even 5 inch props intended for 049 use.

DICKEYBIRD

.020 prop is actually a 4.5x2 but who's counting!

BMatthews

That's what happens when you don't want to run out through the rain to check the tool kit in the shop. You wing it off the top of your head and end up with dyslexia or worse....

DICKEYBIRD

Somebody here on the forum called it "Lysdexia." THAT'S funny![sm=lol.gif]

Bipe Flyer

By zero timed I meant the the timing wasn't set in either an advanced or retarded position and that the timing wasn't tuned to a particular RPM.

When I tried the 5X3 on my PeeWee, the thrust seemed about the same although the top speed may have been less.

BMatthews

Yeah, I know but I couldn't pass up the chance to smack yaz upside the head with SEMANTICS

And besides the ram effect of the air mass inertia DOES play a part. That's why a TeeDee or other hot ported engines don't do well with lower rpms in many cases. The power tends to drop off quicker than the reduction in rpms would indicate thanks to some of the charge stopping and reversing direction before the port can close. Something that a reedie won't let happen regardless of rpms.

At least that's my story and I'm sticking to it.....

baco

Hi all

Sorry....the THING is not yet finished...But waiting for complete wing parts drying, I build a paper Eole, so I can test flyng capabilities.
Of course, stability was a major concern, and first flights were not real flights....many horrorous spin and other out of the book manoeuvers.
But...i worked to modify paper curvature as close as possible to that of the pine-balsa model...and put the CG ahead....and NOW IT FLIES like an arrow...stable!
So I´m waiting for pÃ*eces to dry and finally the 0.049 blue thing makes its first flight.
Regards
Daniel