Precedent Aeronca Champ 1/4 scale

I recently got hold of a Precedent Aeroncha Champ 1/4 scale kit. The
previous owner had partially built the fuselage, but it is not finished.
I did not get the building manual, so i do not have much information of this
kit.
What size of engine will be suitable? I have 3 engines that maybe will fit;
-SC 120 4-stroke
-21cc pertrol, weedeater conversion
-40cc pertol, chain saw conversion
Also, the aluminium wing joiners seems a bit flimsy. Is it a good idea to
replace them with some stronger/bigger tubes?
Reply to
Jon-Magne Johansen
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The 120 glow 4-stroke will be too small. The 40cc gasoline (PETROL) engine will be too large. I think the 21 cc gasoline engine will be a prefect match. It will fly the plane in a very scale-like manner. You'll also probably need the nose weight the weedeater-type will provide.
This plane isn't very aerobatic or fast. Unless it seems REALLY weak, leave it as is.
Reply to
Dr1Driver
I built one and fitted a Zenoah 45. It needed about 10oz of lead in the tail to balance it... It's still giving good service as a glider tug. I would say a Zenoah 26 would suit the plane perfectly. you should consider either the 120 4 stroke or the 21cc petrol.
As for the wing joiners... they're fine as the wing struts take most of the flight loads. I used 8mm aluminium alloy tubes for the struts, anchoring them with some hefty brackets into the wings. Similarly the fixing to the fuselage was stronger than the plan as well.
-- Philip Rawson
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Reply to
Philip Rawson
Mine was... ever seen a Champ prop-hang? or do a rolling circle... or an inverted low pass 3' off the runway? Granted mine had a couple of tweaks... changed the wing section and fitted a 45cc petrol...
-- Philip Rawson
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Reply to
Philip Rawson
"Jon-Magne Johansen" skrev i melding news:ct8jdq$8bh$ snipped-for-privacy@services.kq.no...
Hei Jon-Magne!
I have a Champ in similar state... I do have the the building manual though. I could scan it if you're interrested.
Reply to
TNA
will be too large. I think the 21 cc gasoline engine will be a prefect match.
????
21cc is 1.28 ci. The 120 glow is 1.2 ci. Is the gasoline fueled 1.28 really that much more powerful than the 120 4-stroke?
Reply to
Charlie Funk
The weedeater is not more powerful, but it will allow you to swing a larger, flatter pitch prop at a lower RPM. Perfect for this plane.
Reply to
Dr1
"Jon-Magne Johansen" schreef in bericht news:ct8jdq$8bh$ snipped-for-privacy@services.kq.no...
I fitted a 3W Twin methanol engine (2 x 24 cc) 5 hp. Very realistic sound in it and enough power for glidertug. For balancing I needed 150 gr. in the tailsection. She's an oldie (1985) but still love her.
Reply to
sammyrod
Don't suppose so... then again, I've never had a go in a full size one.
-- Philip Rawson
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Reply to
Philip Rawson
Jimmy Franklin's Waco can, but I don't know if "prop hang" is technically correct. Works for me, though :)
Reply to
John Alt
"John Alt" wrote in message news:IdtKd.1026$ snipped-for-privacy@fe06.lga...
IIRC the late Turbo Raven could...right up until the gear box failed and it pancaked doing a vertical landing.
Reply to
Keith Schiffner
The Aeronca 7AC Champ had 65 hp, making it a slow (85 mph) and low (poor climb) airplane. No aerobatics other than spins; there wasn't enough power to get serious. Even with 85 hp it wasn't aerobatic. The most powerful brothers to this airplane have 180 hp and would never prop-hang.
Dan (lots of real Champ time)
Reply to
Dan_Thomas_nospam
I think it takes a power to weight ratio of about 7 lb/hp ( actually a weight to power ratio...) to climb vertically (continuously), and probably less than five lb/hp to be comfortable for hovering, torque rolls, etc. This is because, to hover reliably, you have to have enough power to have the engine down in the linear part of the torque curve, not at the peak, where it flattens off. Our brains just naturally like nice linear relationships between input and output. Since the throttle is your primary control here, it's nice (necessary in my case) to have at least this control in a linear range. Remember, I'm on your side -Paul Philip Raws>
Reply to
Paul Ryan
actually
Takes an even better weight-to HP ratio than that. An aircraft engine might be expected to produce three or four pounds of thrust per hp at full throttle. Even the newest really powerful aerobatic airplanes with 400 hp or so and grossing around 1800 lb (at a guess) can't hover or maintain vertical climb. The best I've seen was the YAK 55 with the geared 360 hp radial, and it could do some awesome stuff. The gearing of the prop does it: a large-diameter, slow-turning prop gets more thrust per hp, while allowing the engine to rev higher and generate more horses, since hp is a function of torque x RPM. And a geared engine produces more hp per pound of engine weight, so the airplane can be lighter.
Dan
Reply to
Dan_Thomas_nospam
Actually- getting back to which planes can torque roll- didn't the Suhkoi prove capable of it in the hands of that Lithuanian pilot whose name I forget, or never knew. He did a stunt where he'd fly under these stone bridges inverted in Lith. or Russia, then torque roll for a while low over the water, then climb out vertically. Try that... Paul
Dan_Thomas snipped-for-privacy@yahoo.com wrote:
Reply to
Paul Ryan
Dear Sir
Is there any possibility that you still have the build manual for this kit,
as I have bought a 1/4 scale kit on e-bay and although it would appear to be complete, I see that there is no building manual and no engine cowling.
If a build manual was available, I would be pleased to repay any expense that you may have in copying it.
Regards and thanks.
John Sangster Bix House 27 Windsor Road Bray Berkshire SL6 2EW U.K. snipped-for-privacy@msn.com
J> Yes, that would have been nice. Thanks.
Reply to
bentleyblower

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