I haven't been able to find anyone who was able to help me determine the limits of performance so I had to go where man has not gone before. I hope this will help others since they engines are not seen all the time.

Sunday morning Feb 5,2012 at Miramar Flyers field at Miramar, San Diego.

wind calm
approx 400 msl
Top Flite T-34 at 18 lbs wet
RCV 120sp
Zinger 3 blade 17x12 prop

http://www.youtube.com/watch?v=ExC6S...feature=colike

I would like to have one of those engines to play with. Frome what i have heard is they need to have a good cooling set up.
They have the cooling fins machined the wrong way. Yes it is easier for the MFG to make the engine but a poor design. you really need a split cowl with baffels installed so that air coming in to the cowl from the top and exiting the bottom. run it just on the rich side. you will be underpowered on the T-34 but will fly very scale.

I would also look at a 14" pitch if can find one. you are only at 4-5000 rpm max. you will have a good take off run but will not accel to much in the air.

I would think this engine would be best suited in a 70" T-34 at around 10 lbs

Actually this thread was intended to show what is possible for this engine as there are few examples of how much they can haul around.

I did nothing extra for cooling and temp was fine.. flame out was due to low rpm throttle setting.. needed 200 rpm more.
I thought take-off attitude was much greater than scale.. if I would have done that AoA in a full scale I would have stalled. There was more than enough power to haul her around with no bad habits.

That is a scale of an airplane as the full scale.. 17 in prop is scale.. You dont understand these engines at all.. I am turning 4400 to 4600 rpm at the prop which is close to 9000 on the engine.. they are a 2 to 1 ratio. That is why they can turn such big scale props..

What would look better? A Corsair with a big 18x12 4 blade prop or a 2 blade APC.. ? When sitting on tarmat they are turning low enough that it looks just like full scale.

For an airplane not to have an engine head sticking out of the cowl.. that is what I am looking for. Scale power is what a warbird is about.. flying a brick with power doesnt do anything for me as in 3D.

These Top Flite kits really should change their specs.. there is NO way to build any of their kits as light as they spec unless you cover in Monokote which is like kissing your sister, there is NO thrill... They cant handle hanger rash at all.. You can even damage while picking them up. The aircraft has virtually no structural integrity at all.. Painting scale is a joke.
I build very light as an experienced builder. A 70" 10lbs is an ARF... Builders dont do ARFs, again, see kissing sister.

I think it was flying good, and the engine was working well too. They are much more scale like when the prop is more scale in size too.
Thanks for sharing. I was wondering what they really sounded like and how they performed too.
Yeah if I remember there is a little gear reduction going on as they use the cylinder sleeve and it controls the valves so you have a 2:1 gear reduction. Thus you can idle the engine a little faster as the prop spins a little slower at idle, plus the engine has some drag to overcome with the gear drive and sleeve cylinder too.
I have a couple of the RCD .58 CD engines, but I haven't built the twin engine plane for them yet.

I think the problem with the scale planes and painting, et cetera has been there since day one. I remember way back in the 1980's and 1990's where the scale modellers were having problems like that too. I suspect TopFlight intended folks to use Monokote with their kits more than painting them. I think one just about has to go with a fiberglass fuselage and foam core wings for painting to get some ruggedness into the plane to withstand dings and hangar rash better. But then the other problem is weight of course. It sucks to have a really nice scale plane that is overweight too.

1. "Actually this thread was intended to show what is possible for this engine as there are few examples of how much they can haul around."
Yes i missed that i thought you were asking for help

2. "I did nothing extra for cooling and temp was fine.. flame out was due to low rpm throttle setting.. needed 200 rpm more.
I thought take-off attitude was much greater than scale.. if I would have done that AoA in a full scale I would have stalled. There was more than enough power to haul her around with no bad habits."

This is good to know.

3. "That is a scale of an airplane as the full scale.. 17 in prop is scale.. You dont understand these engines at all.. I am turning 4400 to 4600 rpm at the prop which is close to 9000 on the engine.. they are a 2 to 1 ratio. That is why they can turn such big scale props.."

Duh that is what I said.

4. "What would look better? A Corsair with a big 18x12 4 blade prop or a 2 blade APC.. ? When sitting on tarmat they are turning low enough that it looks just like full scale."
where did I say anything about running a APC prop lol Also its called Tarmac


5. "For an airplane not to have an engine head sticking out of the cowl.. that is what I am looking for. Scale power is what a warbird is about.. flying a brick with power doesnt do anything for me as in 3D."
I am not knocking this engine at

6. "These Top Flite kits really should change their specs.. there is NO way to build any of their kits as light as they spec unless you cover in Monokote which is like kissing your sister, there is NO thrill... They cant handle hanger rash at all.. You can even damage while picking them up. The aircraft has virtually no structural integrity at all.. Painting scale is a joke."
so you dont cover in monokote or paint so how do you make your planes scale?

7. "I build very light as an experienced builder. A 70" 10lbs is an ARF... Builders dont do ARFs, again, see kissing sister."
I have seen some kit built warbirds come out under 10lbs with fiberglass and paint.
LOL sounds like you kissed your sister once.

I just wanted to give others some baseline to calc whether they can fly their bird with an RCV vs weight and wing loading and wing type.

Airrap..

3. These engine dont like 2 things.. as you said heat and the other is RPM.. I had originally tried a 15x14 zinger and it was turning almost 6k. The max on the 120 should be around 9500 at the most.

4. ok point taken..

yes, mispelled

6. Glass and paint

7. Humm a Top Flite 60 sized warbird.. that I would like to see. Only on the cheek..

Years ago I had a kit for a .60 size AT6 with a fiberglass fuse and foam core wing and stab. It worked a lot better for painting and was more ding proof too.  Unfortunately it got shot down when someone turned on their radio on the same frequency, at a contest no less.

I couldnt watch the video at work. i did just watch it and yes it flew the plane very well. It does sound like it needs more prop though. I have been around for a while and that sounds close to 11,000 on the engine or 5,500 on the prop in the air. I see you said it was 4,600 on the ground sounds like it really like to unload in the air.

It's good to see it pulling around a plane as heavy as that. The RCV website has a gallery of planes with some data, and there are many in the 14 to 18 lb range that apparently fly quite well as scale models, but seeing is believing...nice job. I think these engines can pull more than people expect because a large, slow turning prop is more efficient than a small, fast turning prop. Especially on scale types with relatively large fuselages, which would absorb a lot of the power of a small, fast turning prop. It looks like your choice of engine and prop worked out great! Thanks for posting.

Jim

video gone

try again.. guys put edited video and trashed original..