I was looking for a balsa sport plane, capable of some basic aerobatics for some time now. Balsa planes get harder and harder to find in local hobby shops… and I didn’t want to ship this large, damage sensitive planes. Some different sizes are available from hobbyking though (not to mention these are often out of stock):
Decathlon .25 EP/Glow 47.4inch Balsa/Ply Kit
Decathlon .46 EP/Glow 62.6inch Balsa/Ply Kit
Decathlon EP 48.9 inch ARF
And even a foam model that comes with electronics. This one has a review on rcgroups also btw. I don’t like foam but if you do this might be a good choice: HobbyKing Decathlon Brushless Plug-n-Fly.
Another valid option for those who like foam is the parkzone super decathlon.
So far for the options I found online. Next is what I really considered buying.
At some point I thought I found a bargain from UltraFly, no electronics, full balsa and already sheeted. Just over 1000mm wingspan looks like a perfect match. Very cheap also but last one in stock. Until I got to the shop. Turned out the last one in stock was already gone. Too bad the website isn’t up to date. This is a good review of the Ultrafly super decathlon.
Eventually I found the Graupner Bellanca, it was twice the price of the UltraFly model. This is a review of the graupner bellanca model, only in german. Couldn’t find any other. Let me know if someone does.
There are some differences I can make up from the UltraFly reviews I read and the experience I have with the Graupner Bellanca. It’s not finished yet, I’m still completing the build. Don’t have much spare time so this will take some evenings.
These are the differences I discovered so far:
Utrafly has a one piece elevator. Therefore you need to cut through wood from the tail of the plane to get it installed. Also the connection could be a weak point.
The graupner version comes with 2 separate elevators that each are connected with their own control rod. These 2 rods then come together with some adjustable hardware towards a single pushrod for connection with the servo.
The ultrafly has a flat bottom airfoil like you can see on this picture from that review. The Graupner comes with a semi-symmetrical that should perform better upside down.
So far I prefer the Graupner version. Allthough it costs twice as much. If the ultrafly would have been available I would have bought that for sure. I like it’s yellow and black colors better and the decals seem to be ironed on using different colors of cover. Much more durable than the blue (!?) sticker decals that come with the graupner kit.
According to this pic the blue seems to be authentic. Not sure if the ultrafly then has non scale windows, or is it the aft fuselage that looks different?
If you start building yours make sure to read the tips in this review about the seagull decathlon. It shows how to remove the sheeting, install the hinges and more.
According to specs from graupner website the recommended motor for this plane has the following specs:
GRAUPNER COMPACT 345Z 7,4V
|Operating voltage range||7,4…11,1||V|
|Free shaft length||17||mm|
|All-up weight, approx.||105||g|
|LiPo battery, Order No.||7638.2G3,5|
|Thrust in N (1 N = 100 g)||10|
|Max. charging rate||27||A|
|Permissible motor direction||R und L|