Great Planes Zero, w/Super Tigre .61 Glow

[Joker 53150]

Here we go, my second official attempt at running a glow engine! My first attempt was a 1.00 Evolution 2 stroke in a 1/4 scale Bud Nosen Citabria. The guy who built the plane had all kinds of errors and problems with his how it was set up, and even after fixing a bunch of problems I just couldn't get the glow engine to run properly. Many say this is because it's an Evolution engine, and they do seem to have a bad rap. Eventually I gave up and installed a 26cc gasser, which powers the plane very well.

Fast forward a few months and I ended up picking up a couple planes that were almost ready to fly, a water plane and this Great Planes Zero. Great Planes recommends a .46-.55 size glow motor (or electric), but this one came with the .61. A little extra weight in the nose and a bit more power than stock, I can work with that.

So after finally getting the new fuel lines and a fuel tank installed, it was time to fire it up. The seller told me he ran the engine to tune it, but the plane was never flown. From what I can see he wasn't lying. The plane wasn't finished enough to have flown, so hopefully the engine was good.

After filling the tank half way I primed the engine and then applied the glow plug starter. With an electric prop it came to life immediately, and idled almost perfectly! It took a little playing around to get it to transition to full throttle smoothly, and I think it's dialed in pretty well now. At least enough to make me happy with my first real glow engine tuning session! Tuning isn't quite done, and I need to do some more programming at the transmitter, but it's running well enough that I'll push to get it done for the next good day to fly. The weekend weather looks like garbage, so that should give me plenty of time to play with it and have it ready.

 

[ElectriSean]

Nice work, the Zero is my favorite warbird... Looking forward to the maiden

 

[SlingShot]

Cool plane. It's fun to say Super Tigre isn't it?

 

[Andrew]

Hi Joker,
Glow engines always have their fuel tank position close as possible to the engine fire wall. This helps the engine stay in tune no matter angle the model is flying in, pointing up, down, inverted and G-Force load.

The way you have it now you have 99.9% chance it WILL lean out too much as the nose rises on take off and then engine stall.

Gas engines (gasoline) are totally different, they have a diaphragm fuel pump built in to the carburettor therefore they can have there fuel tank anywhere you want, usually on the CG.

With glow engines when checking CG it's done with a empty tank.

I would hate to you crash it give up on glow engines because of a minor setup error.

 

[Joker 53150]

Thanks for the tip, the original was set up like that and I never second guessed it. I’ll see if I can push it forward at all. It may have been put there to have it at the CoG, but that’s only a guess.

 

[Joker 53150]

It took some modification, but it's up to the firewall now. It did require that I move the power switch, but if it works better now the effort is worth it.

 

[Joker 53150]

It's been waiting for a while, but weather was great this past weekend (for Wisconsin) so I took the Zero out to a local club located at a sod farm and flew my first glow-powered plane! The Zero handles great, although it doesn't care much for the grass. It took a little extra effort to get a take-off as it kept wanting to nose-over, but once in the air it was well worth the effort. Flight time is about 10 minutes per tank with a little reserve left. My rates should be dialed back a bit, as the elevator and ailerons are a little too effective for "proper" flight.

Dang, I've now got a nitro addiction!

 

[Bricks]

Cannot tell by the picture are you running muffler pressure? If not I would strongly advise it for more consistent running. To me it sounds like your idle is a little rich yet.

I started with Nitro now I am trying to switch everything over to gas fuel costs are nil when running gasoline. Only bad thing about gassers Nitro is having enough space to take off and fly them not like my electrics fly those at home.

 

[Joker 53150]

Yes, I’ve got a muffler pressure line. That video was the first time I ran the engine so it wasn’t adjusted at all. Now that it’s flying it seems to run great, plenty of power and also the wonderful slime to clean up after a flight! You’re right about gassers, and now that I’ve got electric, gas, AND glow I get the best of all styles!

 

[Joker 53150]

A Zero update: this plane is a blast to fly and sounds great with the glow engine (gas would be better, but it still sounds more realistic than electric). The plane does have an issue landing on grass and nosing over, so I installed slightly bigger tires and trimmed the fake retract doors a bit so they don't catch on the grass. That helped, but it's still a warbird tail-dragger so it's only going to get "so good".

The last time out at the field it came in hard due to the engine stopping mid-flight (the joy of liquid fuel) and me forcing it down to avoid a bad landing area. The main landing gear will require a little work, but the tail wheel appears to have most of the damage. The main bracket was ripped out of the thin plywood and two interior stringers were broken. Here's one of the things I really like about balsa models - this is fairly easy to repair and will blend in nicely once done.

The first step is to remove the tail wheel bracket and remove enough covering to really see what kind of damage there is. I don't think this was repaired previously, as that's probably original "quality" cutting from Great Planes...

A couple minutes later and the damaged parts are exposed and/or removed. I'll do a little more trimming of the sheeting so I have some support for the replacement sheeting that will be applied. I may also change the tail wheel assembly to a different brand as this one has damaged the rudder a bit and I'd prefer not to have to do extensive repairs there as well when a simple solution is available.

 

[Joker 53150]

Strange, all these pictures are rotated 90* from how I took them, possibly because of the overall size L x W?

On with the show. The original structure for the tail wheel was fairly weak, made from a thin piece of ply supported by little more than one balsa stringer. My re-build won't be quite as "flush" as it's built from thicker ply about 3x the overall size. It bridges two more stringers as well, and also uses hardwood dowels that reach all the way to the horizontal stabilizer to really tie the structure together.

With the ply glued in place I could add the balsa sheet to finish covering the wound. My new balsa sheet sticks up about 1/32" over the old stuff, but will easily be sanded flush later on. The hardwood dowels are still waiting to be flush-cut.

And here it is, the final structure needing a quick dusting and then some covering. The ply isn't flush like the original so it'll be somewhat visible as structure under the covering, but it's on the bottom side at the tail, nobody will notice!

A couple screws go down into the dowels for a secure mount. This entire setup is much stronger than the original. It also weighs a bit more so I might be able to remove one of the two tail-weights. Covering will take only a few minutes tomorrow night and it'll be ready to fly again for the weekend.