capngriz

My Feedback: (7)

We're looking for suggestions for plans or a builders kit for an EXTRA that actually comes out light. With one of the popular 100cc engines(DA, 3W), our target wing loading is 30 oz. Ideally, it would be a 24-26 lb plane- no heavier!

For the 30 oz wing loading we need at least the following sq/in of wing at the weights below:
23lbs - 1766 sq/in
24lbs - 1843 sq/in
25lbs - 1920 sq/in
26lbs - 1996 sq/in

We need to get this right the first time, so please give reponses/tips on actual experience, yours or a friend. Advertised weights just can't be trusted.

Thanks

Diablo-RCU

My Feedback: (1)

If you want to achieve your target weights, you are going to have to substitute lighter contest balsa. The kit makers can't source the lighter wood because a lot of it is going to China for ARFs. The only 2 planes that I know meet your targets are pre-built and spendy. Troy-Built Extra (Roman Built Extra) and the GB (Genovese Brothers) DR-109.

http://www.gsal.org/projects/branwell-dr109

Steve

My Feedback: (54)

Take a look at the Colombo Anderson 34%

rmh

Well - I took a much easier route --
I bought a fuselage from a H9 - then made foam/balsa wings stabs and rudder .
at 1700 squares - I was under 30 ozs per sq ft . I actually built several .
great performance .
As a hint - ditch the super thick tip airfoils - go with 12%root 10% tip -
use 6-8 lb 1/16" thk balsa sheeting -
you don't have to core any flying surfaces for very light weight if you simply do a neat jub building. AND use 1 lb (exactly 1 lb) foam
I got 22-23 lb all up models with ZDZ80 single and a heavy tuned can .
so the DA 100 would be close in all up engine weight.
The plans I have seen for most of these competition 35 % models are -- sturdy--
Here are three of em we did -
the cute kid is Leah Rojecki
.

capngriz

My Feedback: (7)

I've already had my eyes on the RBM Extra 260 and the 34% CA Models Extra. I would like to hear about some weights for the CA Models plane. I know the RBM is light, it's just a little pricey.

capngriz

My Feedback: (7)

Which airfoil are you using and do you have a set of plans or templates for that particular wing, rudder, and stab? What was the wingspan?

Is is safe to assume you used the H9 97" Extra? If so, I think you're building planes a little smaller - in the 33% range...
Greg

RCPilot100

My Feedback: (4)

I have two Carden 35% Extras and both weight 26# fully loaded ready to fly. They are 3 & 6 years old - before I started thinking real light for Giant Scale - so if I had payed attention to weight back then, they could have been 1-2 pounds lighter.

Dan

rmh

My setups were using the 33% H9 fuselages
However the scale of any of these 33-35% models is so screwed up that one can call em a B-29 .
Ifyou are after performance - it is all about power loading- not speed - power loading.
so we used the slightly smaller model with tons of power .
I don't fuss with airfoils - just make wings as thin as possible while still strong enough.
Trust me on this - it is all that really matters .
But for a model with the wingspan of a 35% EXTRA- I would take the route that others have finally discovered - use the fuselage from a larger scale model which is aproximately the length of the 35% Extra span.
We did this on our first TOC scale model in 1989 ( 10% max scale deviation rules)
OR get out the calculator and take a scale Extra - then clip the wings till they equal the fueslage overall length.
then increase all outlines till that wing span is equal to 35% version.
Different methods of skinnin a cat.
We just re did a Wild Hare Extra - using a band saw --4" off each tip - now it is no longer a 35% but works better --
The lower aspect ratio stuff does the unlimited aerobatics (3D) much more easily- and whack out all the dead weight while you ar at it.
all of these kits are waaaaay overbuilt.
not too strong - just too heavy.

ROMANBM

LOL!!!! NOT TOO STRONG JUST TOO HEAVY LoL!!

RC330LXFlya

My Feedback: (3)

I really like the Yak SP-55M(55SP), but nobody is comig out with one except for Comp-ARF.(read that as I like wood airplanes) All the yaks I see are the 54's. Would it be possible to get a CAD program and make a 35% with my limited knowledge of aerodynamics? Sorry this is kind of off topic, but you guys seem to know alot about this stuff



PS: Comp-ARF guys I am not saying they are bad by any stretch of the imagination I just like my plain old wooden airplanes

ROMANBM

GO AEROTECH I think jonn have a yak 54 or something like that good luck!

RC330LXFlya

My Feedback: (3)

Yeah the Aerotech looks nice,but i like the 55, All that Aerotach has is the 54[]

Diablo-RCU

My Feedback: (1)

Real weights?
Colombo Anderson 34% - 26.5 lb with a DA-100 and in-cowl mufflers.
Colombo Anderson 34% - 28 lb with ZDZ-100 and JMB cannisters.

Never saw a Carden Extra that weighed less than 30 lbs, and I've seen a few.
WildHare Extra 35% - 28.5 lbs with a 3W-106 and in-cowl mufflers.
GB-109 23 lbs with a BME-102 and in-cowl mufflers.
composite ARF 35% Extra 25.5-26lbs with a DA-100 and in-cowl mufflers.
Aeroworks 33% Edge 540T - 29-29.5 lbs with DA-100 and 3W-100 - weighed 3 of 'em.
H9 Cap 33% - 24lbs with ZDZ-80 and in-cowl muffler.
My scale is calibrated and accurate, traceable to NIST.

Rcpilot

My Feedback: (78)

Mike Hurley Extra.

I've seen a 2 of them fly. Both had DA 100. Both at 6000' above sea level. Both AWESOME with the right thumbs on the sticks.

Rcpilot

My Feedback: (78)

Mike Hurley Extra

It's actually a smaller fuselage than 35%. I think it's a 33% fuselage, but don't quote me. Wings are 35%. It's lighter and less drag than a 35% fuse.

Use contest grade balsa where you can and don't overbuild it, by changing Mikes' design.

Weights? Can't say for sure, but if they fly light on the wing at 6000'-- you oughtta be just fine at sea level.

I've seen a 2 of them fly. Both had DA 100. Both at 6000' above sea level. Both AWESOME with the right thumbs on the sticks.

capngriz

My Feedback: (7)

Yup, I've flown the Hurley Extra with a 3W 106 QS and it is an awesome plane. It's so responsive, I can could do rolling harriers on his low rates (which were quite low)!!! The problem is that they are coming out 28 - 30 lbs in most cases - at least the two I've seen and others I've read about. I just want a little more pullout power. I will say that the one I flew was not obsessively light - ie. no carbon fiber gear, tail wheel or spinner and not the lightest wheels.

Great feedback so far.

Dick - I like your ideas, but I need help with the airfoil. I can't just go cutting foam....well, my buddy does that part.

PJFaller

I cant seem to get why some guys are so hung up on wing loading and weight. Yeah I agree its very important but to what extent?
I have flown many different full scale and Rc airplanes and I can honestly tell you that a heavier airplane flies better, within reason of course. As far as a 35% airplane why you would look beyond a Carden extra 330 at 35% because of the weight is just beyond me. Im not bashing any products out there because I have not flown some of them but I can tell you that in my opinion the Carden's are the best kits on the market bar none. I have had 10 of them, and never has one failed me. yes they are a little bit more heavy than the rest but the power thats available to us through the new awesome engines that are out, who cares! 5 lbs more than anything else, and yes there is a difference, but a pound or two come on now. Snap exits on the heavier airplanes are crisper, and high alpha and 3d they just feel better. why do you think in the XFC most of the airplanes that competed were Carden's. And why is there always at least five at the TOC. Says something doesnt it. Ive built several of these things bone stock and they just kick ***. Durable airplanes that can take a beating, and if you've ever seen the kit, its a work of art. edge trued sheeting that you cant even find light through the seem after taping it together. Im not bashing anybody here as I said, I just think to overlook such a good proven product is crazy for maybe 1-2 lbs. Im not sponsored by Carden, just a very happy customer. I have another one coming next week I cant wait to get started on. Give it a look Im sure you wont be dissapointed.

Pete

rmh

As long as you like a setup - stick with it .
weight IS the enemy of a good aerobatic plane tho -
I never saw one which was too light - never ever
too badly designed/ fragile crummy integrity - yess - too light -- no.
even full scale - the best ones have the best power loadings and lowest wing loadings
Look at any of em - geting rid of weight and increasing power is what it is all about.

ROMANBM

Some body say the heavy plane is better?? what? . NOT A PROBLEM BUY LIGHT PLANE AND ADD WHEIGT TO IT !
AND THAT IS THE END OF YOU PROBLEM

(OWNER OF REALY LIGHT PLANE )

PJFaller

No I did not say the heavier the better, but a properly loaded airplane flies ahell of a lot better than a lightly loaded plane as well as a heavyily wing loaded plane. Thats what I meant if you did not understand my reasoning. Trying to get real light does not always work in your favor. Ive seen very lightly wing loaded airplanes fly and they just dont track and respond as well as a properly loaded plane. thats the point Im trying to make. Many manufactuers have done the research and gotten their own wing loadings to where they want them and we all can see the obvious results. My piont was a lot of people bash the 35 carden extra because it is heavy. Its not heavy it is properly loaded. How do I know this. Look at the way it flies!

Pete

ROMANBM

Ok I think the everybody like overpower plane and for DA 100 cc up to 25, 26 is ok but 30 lb [&:]

Bryant330L

My Feedback: (126)

My 34% Columbo Anderson Extra 300 weighs 23.9 lbs with a BME 105. It shows it's weight in the way it flys as it is a real floater. I didn't expect it to come out that light so I weighed it 3 different times on a set of digital scales. The scales don't lie, that is just a light airframe and when you put the right motor on it you come out with a real light RTF plane. I didn't add smoke, a pilot or any other additional items, but I think it could handle the weight with no problems.

Not trying to start any arguements here, but I went to the XFC, and the reason there were so many Cardens there was because of who runs that event. There were a couple of Carden flyers there that didn't seem to be anything special. They are nice flying planes but if any 35% plane comes out to 30lbs that is a design that could be improved upon.