GP Super Decathlon
 

Hi everybody. I just wanted to share a picture of my first kit I just finished yesterday. It is a GP Super Decathlon I bought 10 years ago and never built until now. I decided to cover it in a none scale sceme for two reasons. First because here in Greece it was impossible to find the right monokote colours for the decals provided and second because it is my first covering job and I wanted to keep it fairly simple. I use a O.S. .46LA and Futaba 6XAs with S3003 servos and a PCM receiver. I will add some trim to the covering, but this is more or less how its final look will be.

If anyone has any tips about flying this plane, since it is my first taildragger too, I would really apreciate them. I plan to fly it next weekend. Wish me luck!

RE: GP Super Decathlon
 

Make sure that the CG is right. If it's the slightest bit tail heavy, you may not be bringing it home in one piece.

RE: GP Super Decathlon
 

I have this plane and success depends on your flying experience. Many have had problems flying this plane because the assumption is that since it is a high wing plane, it should fly like a trainer. Thats not exactly the case. Setup is everything on this plane. It is actually a pretty wild and wooly aerobatic plane and CAN be a lot of fun. But for a novice, I would recommend the following throws: 1/4" rudder, elevator, ailerons. That tones it down quite a bit until you get the hang of it. If the landing gear get spread out a little the ground handling will be hard to manage. Its a very short coulple aircraft. But once your used to it, its a ton of fun. Mine is about 12 years old and is currently being recovered and put on floats.
Edwin

RE: GP Super Decathlon
 

SERAFIM

Looking forward to your flight report. My GP Super Decathlon has been under construction for over 5 years. I've built and flown at least a dozen airplanes (mostly warbirds) with this thing sitting on the back burner. All the negative comments on it's flight performance seem to have faded away so my interest in this airplane is coming back. At this point it's 95% complete and looks gorgeous. We're lucky we delayed building the GP Super Decathlon and have all this great advice to work with. I intended mine to be a floatplane from the start so it has an OS91FS and sits on the 36" Goldberg Anniversary Cub floats. Hope to hear more from Edwin too.

Gary

RE: GP Super Decathlon
 

Thanks for all the anwers guys. It' good to know that there are others still having this plane. From the things I have read about it I thought that every single one of them crashed and burned during its very firsrt takeoff and mine was the only one left in the world, just because it has been sitting in the box for the past 10 years. I have even downloaded a video of a mix of several crashes and the GP Super Decathlon was the only plane that crashed 4 or five time in the same video!!! And most of them were during takeoff. Well I will make a video of it, if one of my friends is brave enough to stand close enough while I fly it (or try to fly it, anyway...). I hope I post it on this forum and not the one about Crashes. I'll keep the throws down and try to give it time to pick up speed before taking off. Thank god the runway is an abadoned full scale one. I think it will be enough. Have to be optimistic!!!

RE: GP Super Decathlon
 

That landing gear is pretty flimsy. I bought a fiberglass gear that pretty much fit perfect with no mods in the old mount. I think it was the dubro fiberglass gear. I've seen them at all the hobby shops around here. Pretty common. If you are new, I wouldnt do a spin for a while. At least until your good at spin recovery. This plane will do an evil snap if you have too much elevator and go into the most beautiful spin you ever saw, right into the ground. I managed to recover mine right as it went behind the tree line. My motto is "Never give up until you hear it the ground". I gave it a touch of up elevator and up it popped from behind the trees. Had to do a clean out in the porta potty after that one.
Edwin

RE: GP Super Decathlon
 

biggest problems with that plane was that it is short coupled, not a problem with proper balance and throttle control on takeoff. Biggest problem is that like all Great Planes kit it's a porker. It really should be about a pound lighter. The wing loading gets high really quickly on this plane. If you master the takeoff the plane flies great, But be warned if you try to force this plane off the ground before it's ready to fly it will snap and bite you on it's way down.
Dennis

RE: GP Super Decathlon
 

I have built and flown several of them. Very fun plane to fly, it always keeps me on my toes. Most of what I have to say has been said, but here goes...... Give it throttle slow and gentle , DO not jam it to full like most do. Keep your ground speed up, don't force the take-off or you will be picking up some balsa. Keep your elevator throw LOWER than the manual says, too much throw and she will snap when Up elevator is given. Other than that, a nice flying plane. As it was said before, keep her light, and she will fly much better. Have fun flying! Keep us posted! My photos are of my current decath, been with me about 4 years now. O.S. .50 SX

RE: GP Super Decathlon
 

You may want to practice some rudder and elevator only flying if you haven't already. The Decathlon will continue to fly after it has slowed down enough for the ailerons to become ineffective, be ready for this situation with some rudder control and you will do just fine. I've had 3 of these in the last 15 years, one is awaiting finishing in the shop at the moment, with a .70 FS in the nose, it is truly an unlimited aerobatic performer. As stated before, this plane is probably a lot more fun to fly for an experienced pilot than it is for a lesser experienced flyer.

RE: GP Super Decathlon
 

Yesterday was the first attempt to start and break in the O.S. .46LA. No luck, though, I think because my 12V battery charger does not work and the starter did not have enough power to turn the prop. Got a new one and will try again today. I have a question for you. Can I have over-tighten the prop nut? I know that a new engine is a little hard to turn at first. And a final note. This is not my first plane, it is my first kit. All my previous 4 planes where ARF's. Thank you all for the input.

RE: GP Super Decathlon
 

I have one, too. I have owned mine for almost four years. It is a great flyer but care must be taken. If you follow these rules you'll have a great relationship with your plane:
NEVER force it off the ground. Build up plenty of speed before you pull the stick back.
NEVER try to fly low and slow. It will snap without warning. I crashed mine on the third flight because I got too slow during my landing approach. It was rebuildable but barely. Since then I keep the speed up and haven't had a problem.
DON'T try to do a three-point landing. It will bounce-bounce-bounce all the way down the runway. Wheel land. This may sound contrary, but trust me. This plane does not like 3-point landings.

With the negatives out of the way, I can say some good things. This plane will do the neatest snap rolls you'll ever see. It will climb in knife edge given enough power, and flys well inverted. There is a little roll-coupling but it isn't too bad.

I think that you will find your plane is underpowered with a .46LA. You might want to consider upgrading to a .46AX or a .50SX. I powered mine with and Enya .50CX, which is a powerhouse, but I could still use a little more. Your plane should fly and be enjoyable with the LA, but it will limit you somewhat.

If you remember to follow the three rules you should have a long happy relationship with your Decathalon.

RE: GP Super Decathlon
 

Thanks for the suggestions, also its good to hear some good things about it. I run a couple of tanks of fuel through the .46LA today and only taxied it around for a while. I have to practice ground handling first before I attempt to get it up in the air. The engine seem to be working fine. ksechler, I know that this engine is not the best choise for it, but it is all about money. O.S. .46LA kosts $150 in Greece, which as I can tell is almost 3 times its price in the US. Futaba 6XAs with a PCM receiver and four 3003 sevos was almost $600. Living in Greece has its advantages, like perfect vacation spots, but we have many downsides. RC modelling is very expensive here. Well, what can we do...

RE: GP Super Decathlon
 

Can anybody give me an idea on how to route the receiver antenna? I cannot attach it at the top of the fin, because the rudder is there. And, if I route it through the fuselage, where should it come out so that it doesn't interfear with the tail weel, rudder or elevator?

RE: GP Super Decathlon
 

Hi,

I killed mine few months ago. It was really great flyer. I powered it with Magnum XL .61. Lot of power and fun.
Yes, it was hard to handle on the ground on the beginning, but once used - was great.

http://msi.pl/~mirage/modele/images/...16.05.04/1.jpg


Now building a bigger one: Dyna Flite Super Decathlon. It's a giant scale version powered with ZDZ-40 gas engine.
http://rc.marekszulen.net/dyna-deca.html

Regarding to the antenna: I had it on the upper side of fuselage until the end. The rest freely hung out of the fuselage.

RE: GP Super Decathlon
 

I just ran my antenna to the top of the fin then turned right down to the stab. Didnt seem to make any difference in flying.
Edwin

RE: GP Super Decathlon
 

The big day was yesterday! I went at the "field" (it is actually an old abandoned sailplane strip). The weather was foggy but there was no wind. I found somebody else to check it, because I haven't flown for 4-5 years and I was very nervious. Everything seemed ok, so he took off, trimmed it (it needed only one click for the ailerons but a few clicks of down elevator) and gave it to me. To cut a long story short, here are my first impressions of the plane. It is difficult to handle on the ground but not impossible. I have read many bad things about it here, so I was expecting it much worse. Take offs need attention to keep them straight, but when it picks up speed, it takes off very nicely. Maybe a factor for that is that mine is not overpowered (OS .46LA). The engine is perfect! It is very reliable, and I can fly it around at about half throttle. I did not try any aerobatics because I am very rusty, only a roll with just aileron, which was far from perfect, propably because I kept the thoughs down for the first flights. Now, landings. I have always had a problem with landings. The good thing is that this runway is very long and wide, as you propably will be able to see from the picture I will attach. Landing this plane seems easy to me. I cut to idle and let it sink, controlling the descent with elevator. I bounces a couple of times but thats it. With practice I think I will be better. Well, thats all for now. I will get better pictures of it next time. There are a couple for now. It is a great feeling driving home with as many pieces as you had when you went to fly a new plane, especially your first kit.

RE: GP Super Decathlon
 

Congrats! I am glad this worked out well for you. If you figure out how to stop it from bouncing let me know! I still bounce mine sometimes and I have been flying it for almost 3 years.

RE: GP Super Decathlon
 

Thanks Serafim...that's exactly what I wanted to hear. I'll let you know how my flies...hopefully soon.

RE: GP Super Decathlon
 

ksechler, thank you. I'll let you know, either way

bent, I'll be waiting to read your impressions. I guess keeping it straight for takeoff will be easier on floats. Lucky you

Edwin, you are right about the landing gear. I checked it this afternoon and both legs needed a little bending to get the weels back to vertical. I didn't make perfect landings, but I don't think I will get much better than that soon. I might have to change too

RE: GP Super Decathlon
 

I finished mine last year, but did not fly it until this spring. It flies great, once it is in the air, but ground loops like a son-of-a-gun on takeoff. The last time, I tried to recover from a squirrelly takeoff, and the prop bit the ground and flipped the plane around damaging wheel pants, tail feathers, and landing gear. I am near finished with repairs now.

I have a Saito .72 (inverted) in mine, finished as on the box (red/white) with all graphics in Monokote (don't use the star stickers, they don't match). I moved my landing gear back 1/2" and twisted in 1 degree of washout in wings. I tried for 2 degrees, but they were too rigid to twist, even with soaking and weighting. GP website tells you about the washout and moving landing gear in their tech update.

Take off from grass, not pavement. That will help (so I'm told) keeping it straight on takeoff, and I plan on doing that when I get mine back together. I did not like the recommended aileron rates in the plans (too mild), and plan on increasing them, but other rates were good. I have not had any problems with stalling as others have mentioned.

I ran my antenna out the bottom and connected it to the tail gear with a rubber band. The landing gear held up well (until my last crashed takeoff), although I did build in balsa gussets at the outside of the gear where it meets the fuse. This not only looks better, but it gives the aluminum some added support from flexing at the bend.

These are really great looking planes, and a fun kit to put together, but be careful on takeoff!!
Pilgrim

RE: GP Super Decathlon
 

Here is a medium quality video of it

http://users.hol.gr/~verotech/Plane_0001.wmv

Talk about bouncy landings!!!

RE: GP Super Decathlon
 

I have read all of the posts and I am a little concerned. I have purchased a NIB kit from an individual. Great Planes has discontinued this kit. This will be my
first build. I used to build when I was a teen (40 years ago) and flew via "control line." I am on my first trainer, a Hangar 9 "Alpha 60." I have a lot to learn
so I will not be flying the Super Decathlon for sometime, but I wanted to build something I would be proud of and that would give me incentive to work hard on my trainer. I have a new Evolution .61. Would this engine be adequate? I will be using a JR XP 8103 and I have a JR Quattro that I can use for a buddy box for initial training. By the read of your posts I will certainly need some, when the time comes.

CAn any of you give me any tips, information, that could save me some "pain" during the building process. Modification, accessory purchases, etc>?

You help would be much appreciated. I have subscribed to this thread and will check everyday. Way to go, Serafim. Great job!:eek:;):D

RE: GP Super Decathlon
 

Hi,

Mine was powered by Magnum .61XL engine.
It has plenty of power. Watch out CG. No modifications needed.
Flew great.

RE: GP Super Decathlon
 

jimvines4244, I think that everything about this plane is already stated in this and a few other theads. Let me sum up with a few comments:

1. The .61 should be great for this plane. Mine has an .46LA, I can fly it around at half throttle, but more power whould be usefull. For example, to perform a loop I have to dive a bit to pick up speed. Mine balanced exactly on the recommended CG with this engine, so you might have to move the battery and/or receiver back for yours to balance. The recommended CG is just fine, I think

2. It's gound handling is bad. Advance the throttle slowly. Let it pick up speed before rotating, because it will tip stall. I don't know if your instuctions suggest washout, mine didn't but I know that GP suggests on their site to add washout and later kit instructions were changed to include that. I didn't build any washout and I don't have a problem. It might be better if you do. It's up to you

3. Keep the control thoughs down at first. 1/2" each way for all contols are enought at first. Later you can increase them

3. Landing are bouncy and landing gear are not very durable. I have order a Dubro LG, which has not arrived yet, which sould correct this problem

Thats about it. Give it time, build it straight and if you don't have any experience on taildraggers, practice on the ground until you are comfortable with its handling before trying to takeoff. In my opinion, landing are easier with this model than takeoffs. But that's me

Good luck and let us know how it goes

Serafim

RE: GP Super Decathlon
 

Thank you, mRqs and SERAFIM for your replies. You have been very helpful. I am hanging onto this thread. I will get the kit probably next Monday or Tuesday. Can't wait.

Will keep you informed and may have questions as the build progresses.

Sincerely,

Jim Vines Jr.