Guys,

I remember being amazed in the past with the beautifull idea and theory of a Wankel engine[X(], but I thoght nobody was using this type of engine.
I just saw a O.S. .30 Rotary 49-PI Wankel engine to be sold and would like to know if someone have already tried one of those?
Just the price is spicy[:@]

Nilo

nilo, a club member I fly with has one in his Yellow Aircraft 30 size Sukhoi. It flies very nice and look like it has plenty of power but it really sucks the fuel... just as soon as it gets in the air, it seems like he is already making his landing approach.

i gots one of thems . on a sportsman avition waco 30 . it ant what you call power but flys it scale . sounds better if strait piped no it won't hurt it . but a cool engine if you never have 1 lean run or bad fuel they will not work if run lean . don't try to put it in no aerobatic plane unless its a waco . it just dont have power . about like a os 25 la .

Your right about the price. Spicey indeed!!! I remeber when they made it to flyers back in the eighties. A lot of guys where putting them on the Sweet Sticks or similar. Made them look better any way. Drink fuel, oooooh my !!!! They drink fuel like a good .60. or better. I understand the modelers in europe still use them, but they aren't as popular as they used to be. [&:]

I have a wankel and it does suck fuel. It burned 8 oz in 6 minutes! By contrast, my Webra .32 burns 8 oz in 15 minutes. Same type of flying.

It is a nice engine and definitely draws attention, but the fuel consumption just wasn't acceptable to me. Also it runs very hot. If you cowl it in, you need to have plenty of flow through. Even uncowled it always seemed like it was on the verge of over-heating.

Really too bad about those two things because I like the engine, but I doubt I'll ever use it again. It just sits in my glass cabinet as a conversation piece now.

This page on my website has a little more detail about the engine and you can see it mounted to the plane.

http://www.airfieldmodels.com/galler...k_30/index.htm

Well wankel engines don't suit themselves well to airplanes, they have three combustion chambers vs one and every body knows that three small cylinders are weaker than one of the same size. That is why they suck down more feul, three fires per a rotation vs one, you also have to add in the slightly rich setting to help cool it and the higher rpm that these engine like to run at. It works out to be almost twice the comsumptin of feul just to run at the same rpm as a compriable .[:-]30 two stroke.

PlaneBuilder - I had mine leaned to max RPM and it was spewing out raw fuel the whole time. Yikes!

Yeah, they need the extra feul to help them cool, just look at a mazda rotory engine, the radiator is huge to help disapate the heat generated by the engine. If I remember correctly the carb that os puts on it is the same as the sixty size fp motors. Without the extra feul it would burn[:-] up the internal seals and rings.

The os wankel motor makes a awsome paper weight, it sits pretty flat and has a good amount of weight to it.[:-]

I guess these RC wankel engines need mucth more research, since the big ones, designed for real cars, are considered the most efective, specially when talking about fuel consuption.
The truth is that this engine doesn't have three combustion chambers. It does have instead one rotating "triangle" that creates three diferent function areas, fuel intake, combustion and exaust areas.
The advantages of the wankel engine (not the RC one) would be:

In addition to its performance dynamics, the rotary engine offers many other benefits. Because the rotors move in a constant circular motion, instead of back-and-forth like pistons and valves, there is very little engine vibration, eliminating the need for counter-weights, balance shafts and other response-slowing compensating systems common to conventional engines. And because it never has to change directions, the rotor’s momentum is never lost, providing a smooth, even distribution of power from start to redline.
Mazda has one comercial model that uses the wankel engine and won the 2003 International Engine of the Year, beating BMW, Mercedez,all of then.

Wankel explanation including motion view can be seen at:
http://www.keveney.com/Wankel.html

or at Mazda page below:
http://www.mazdausa.com/MusaWeb/disp...de=RX8#renesis

Nilo

Maybe you should look again at your little moving diagram, the wankel has one rotor that does three of the same functions in one revolution, each chamber rotates into that area to perform that function. Itake> compression>ignition>exaust and the next chamber is following suit as well as the last one of the triangle. True the engine has one combustion area but three rotating chambers. and it is geared if I remember 3/1 so you get three fires per a revolution.
Being a ex automechanic and rebuilding these motors they are intricate and need special care when it comes to fitting the seals (rings). The mazda rotory is olny 80 ci displacment but it can produce upto 326 hp from a twin turbo setup, yet that has been refined and tweaked for many years and it has a seperate oil system and cooling system that the glow feul serves in the os engine.

Guys that buy these are not worried about gas consumption. They look cool and sound even cooler, in my opinion. The only reason the never over took the standard internal combustion engine is the combustion chamber seals wear out so fast and the hp's go with them, but there power to displacement is unreal. Even in the new Mazda's at a 100,000 mile the loss of horse power is very high(but the salesman won't mention that!).

I'm wondering how sounds this engine[&:]


Nilo

Nilo - Sort of a cross between a 4-cycle and a 2-cycle. Closer to a 2-cycle probably.

they sound like a 3 cycle . well they just about not are . they really sound like a rotax 503 to me i run without the muffler . nobody cars about the nosie that flys there hehe . they don't have the pop that the other 2 strokes have.

I bought a Mazda 808 Couped when they first came out. It had the rotary in it and I loved the engine. It had lots of power (burned out two clutches), and would just keep accelerating. I had it out in Southern Colorado by the Sand Dunes national monument where there is a stretch of road that is flat and straight as an arrow for several miles. Got it up to 130mph and it was still accelerating so I backed off. Not worried bout the engine, but if I had hit a paper cup, the car would have disintegrated. If you could get one for RC that had the power to weight ratio that mine did it would scream.

This is a members plane and the wankle engine
moves this plane very fast. We call it the bat at our club.

Randy,

Have you noticed that the engine overheat or that it sucks fuel too much?
What's your overall evaluation?
Where did you buy for how much?

Nilo

First of all this is not my plane. The guy that owns it
flys it alot and has no over heating problems
at all while in flight. But he told me that after each flight
you need to let it cool down a little before starting
it back up again and flying it again. I think it does
use a little mor fuel cause he ussually flys for only
8 to 12 min. But this plane is wicked and if you fly wide
open throttle for 8 min or so you are ready to set it
down because of the high control demand. Yes I
have flew it but only for 5 min and thats all i wanted
of it cause its a hand full.

He has had this engine for a long time and it runs great.
I think the wankle engine runs about 350.00 USD.
Would i buy one No not at my age but if i was 20 yrs
younger and i liked speeeeeeeeeeeeeeed yes i would.