bluelevel

My Feedback: (39)

Since there is not a whole lot info on this super nice plane, I thought I'd share a few pictures of this build. Because of other projects waiting in line, I set myself a time limit of 10 days to get this bird done. So this time there will be no fancy radio trays, to paint inside the fuselage or other time consuming gimmicks. Just a clean and functional build.

I'd like to point out that this is one of the highest quality planes that have come across my building table so far. The paint quality is excellent and right on par with Carf Models or Pirotti planes. The skin has a very high gloss finish and feels a lot harder than the Skymaster lay up for example. I have built numerous jets from almost any manufacturer out there but this is by far one of the lightest models besides purposely-built 3D jets. I will post pictures of the internals of the fuselage the next days so you'll see what I mean.

I started with the rudder and stabs. Except for the fact that I had to open up the slots for the servos a little bit, this part was pretty straight forward. As usual I am using control horns made by Gabriel in Germany instead of the factory hardware. They are made from a carbon-fiber reinforced thermoplastic and are super easy to install.

Thomas

Viper1GJ

My Feedback: (20)

Looking forward to seeing photo of your build.

Where do you get the rudder horns shown in your photo? Do you have a photo of the horns before they are inserted into the surface?

Thanks,
Gary

Bob_B

My Feedback: (11)

I really like the moulded controls horns, gives it a really professional appearance!

bluelevel

My Feedback: (39)

Below you'll find a picture of the control horns. The most common sizes I use are 20mm height, 27mm height (mostly for the rudder but depending on the geometry I also install these for flaps) and 35mm (would only be required for giant plane rudders like a Havoc). You can only order these in Europe, I get them directly from the factory at http://www.gabriel-stahlformenbau.de/shop/

Thomas

bluelevel

My Feedback: (39)

The wings are also done, I opted for 20mm control horns for ailerons and flaps. Servo arms are 1'' for ailerons & rudder and 1 1/4 for flaps.

The bay for the gear had to be opened a little bit to accommodate the Electron retracts. Although covered with carbon fiber, the wooden rails for the retracts seem a little soft to me. I appreciate building light but some higher quality plywood would not hurt in this area.

Also it took quite some time to install the flap servos through the root rib. A nice cover similar to the cutouts for the aileron & rudder servos would have made this surgery a lot easier. I went with a regular "above skin" linkage for the flaps, although an internal linkage would have been nicer. As mentioned previously, this build needs to be finished in time, so I didn't want to spend hours fiddling with the servo arm and linkage without proper access.

I also do not understand why the factory did not put in a servo mount for the aileron servos. The plywood former you see in the picture did not come from the factory.

Other than that I want to stress again how impressed I am with the build and paint quality of Redwings!

Thomas

Bob_B

My Feedback: (11)

www.lindinger.at is one source.

https://www.lindinger.at/en/?sViewpo...=Control+horns

bluelevel

My Feedback: (39)

I started working on the fuselage now, first was to cut a battery tray that will go in the nose. I have attached a few pictures of the inside of the fuselage to show how light this plane is built.

Thomas

bluelevel

My Feedback: (39)

The nose is completely done. I hinged the gear door and installed a MKS HV747 servo, this is the strongest high voltage servo in it's class. The receiver batteries are Jeti Li-Ions.

I also attached a picture of the Electron nose gear. I have used Electron retracts several times before and I like how strong and well made they are.

shepga

Thanks for the Leonardo build thread. The Leonardo is my first jet. Been flying Pattern/F3A for 20 years, time for a change. Having built many fine quality pattern planes I can also say the quality and finish of the Leonardo is superb. I will be following this thread with great interest. I'm sure I'll have some questions along the way.

berthoud

My Feedback: (35)

The Leonardo is the best flying aerobatic/sport jet that I have flown in years including: the Paritech Viper XXL, Tomahawk Futura, EA Shockwave and Paritech Natrix. Coming from a f3a background you will really enjoy it. Blue level, you will want to reinforce the fuel tank structure if thats one of the original versions as it appears it is. I personally would not do the servo actuated front door if I were to build another.

Scott

RBardin

My Feedback: (27)

+1 on the tip to beef the tank mount. Especially if you plan to stack another tank on top for smoke or more fuel.

Depending on your particular engine length, you may need to move the tank forward or shorten the pipe from the front. This model needs weight forward anyway, so moving the tank forward and adding more structure will kill 2 birds with one mod.

What engine are you using in this one?

bluelevel

My Feedback: (39)

I will be using a Merlin 200

Thomas

berthoud

My Feedback: (35)

The Merlin is a fantastic motor for the 3m Leo. I would keep the tank in the stock location to minimize CG shifting as fuel drains. You will not have to alter anything with the Merlin and stock setup and with the three batteries up front you should not need any additional weight.

Scott

bluelevel

My Feedback: (39)

Got a lot more done the last 2 days. The radio & equipment tray is done and I was able to complete the whole wiring. I'd guess that there are at least 30 feet of servo wire in this plane.

Tomorrow I will work on beefing up the tank mount, complete the smoke & fuel tank and the plumbing.

Thomas

RBardin

My Feedback: (27)

Looks good, Thomas!

Scott, where's your C/G set? I was told to put it "on the mains" But it would be nice to have a more accurate setting.

bluelevel

My Feedback: (39)

Attached are a few more detailed pictures of my build. These show the fuel and smoke tank (a juice bottle) as well as the beefed up tank mount (I added a few braces).

She is finished now, I was able to program the radio & gyro today. I set the CG per the factory recommendation at 30cm behind the leading edge of the wing. To achieve the proper CG I needed 10oz of lead in the nose. The plane is still very very light on the nose and will easily tip on the tail when the canopy is not on.

Assuming that she stays in one piece for the maiden tomorrow, I will post some more pictures of the plane all together soon.

Thomas

shepga

Bluelevel, looks great and professional. You have motivated me to kick my build into high gear. Do you have any photos of the tail pipe installation? I'm particularly interested in the rear. How did you get the back end of the pipe through the last ring at the rear of the fuse? How much of the pipe extends beyond the fuse or is it flush with the back end of the fuse?

theosoarus

Hi.
I just finished my Leonardo and test flew it over the weekend.
My kit has the recent fuselage modification with the moulded fuel tank and engine mount but I found all the same issues you have with the retract mounts, servo hole sizes in the flaps and elevator along with nothing to mount the aileron servo to.
However the additional work wasn't too hard.
The model flew perfectly!.. One click of up elevator and it was perfect.... I felt just as good if not a little better than my old Futura 2.5.
I'm running the Jet Cat P220Rxi so I needed to add a little bit of nose weight and I added an extra fuel 1.6ltr tank.


Cheers.

bluelevel

My Feedback: (39)

Maiden is done! Except for some trouble with the nose gear door (have to change the hinge point) and an awful howling noise the plane made at higher thrust settings, it all went well. The noise is not that high pitched whistle that you get when the pipe / exhaust cone gap isn't right, it was different. I assume it comes from the trailing edge of the fuselage where the trust pipe ends. I moved all equipment forward as much as possible and the thrust tube of my Leonardo sits almost flush with the end of the fuselage, but doesn't stick out. I guess the noise comes from the little lip that's left. I guess I'll have to move back the turbine and the tube by about half an inch to clear the back of the fuselage.

Thomas

bluelevel

My Feedback: (39)

After the first few flights, I think that the factory recommended CG of 30cm is a bit too tail heavy. If you like a hands-off inverted flight this might be right for you, but I prefer a minimal down elevator to keep the plane level. This will also help the ground handling, as the plane likes to tip on its tail with the canopy off.

The factory throws were spot on, but I still have to experiment with aileron differential to find the perfect setting for axial rolls. Also I put in some crow to help the landings, this plane will glide and float forever.

All in all a perfect plane if you are into serious aerobatics. The Leonardo presents super nice in the air and does aerobatics with ease at slowest speeds. If you want a speed demon this will not be your favorite plane, though.

Thomas

RBardin

My Feedback: (27)

Congrats Thomas and Theo! I maidened mine this weekend also. It flew well with a JB220, and also required a bit of nose weight - even with 3 big batteries in the nose. Mine sits on the tail with the canopy off - but only with no fuel.

C/G was set in the middle of the main strut location with maybe 1/2" of fuel in the tank. I didn't fly it inverted to check for neutral but it will hold a knife edge at 1/3 throttle

Rusty

berthoud

My Feedback: (35)

Congrats guys, you will love the plane once you get it dialed in.

I have attached several pictures of the velcro mount I made for the fuel tank. Having accidentally ejected Pascoe's tank last year at FIF I felt a necessary upgrade to the stock wood formers.

Pablo, who previously owned mine, indicated he added the shown vertical reinforcement via laminated CF formers as shown in the pictures to minimize fuse flex.

Finally, picture attached of tail pipe. No unusual sounds at any throttle % with the Merlin 200.

Your CG sounds about right, model may fall to tail without canopy (batteries, no fuel) if bumped.

Scott

bluelevel

My Feedback: (39)

Due to the unusual crazy winds we have down here since weeks, I didn't get to fly "the guppy" as much as I wanted to, but I was able to dial it in a little bit better.

The awkward howl it made at higher thrust settings is gone now. I moved the thrust pipe and the engine back by half an inch, so that the thrust tube now sticks out the fuselage.

I also removed some of the nose weight, my current CG is now at 300mm measured from the leading edge of the wing. This feels better now, but I might remove even more nose weight. The factory pilots recommended a GG of 310mm for a perfectly neutral plane. The only disadvantage is that this will worsen the ground handling. The plane is so light on the nose already, that it kind of bounces over bumps in the runway instead of filtering them. Also it will tip on it's tail with an empty tank and without the huge canopy being put on.

My plane also has an annoying whistle coming from the flaps when these are deployed. This is because the opening between the actual flap and the wing root is wide open and not sealed. I have fabricated a sealing lip by cutting quarter round strips out of a CF tube I had laying around and glued these on the flaps (see picture). I haven't flown it yet to see if this has helped, but I am pretty confident that it will make the flap whistle disappear. These sealing lips are standard on most planes, so this is something that should be incorporated in all current planes leaving the factory.

My Leo now has a brother at the field, more are to come!

RBardin

My Feedback: (27)

If the right springs can be found that would allow the rear articulating struts to actually articulate, I think the ground handling and tip up issues would disappear. Otherwise, for straight struts, the main gear on this model should have been placed 1/2 inch further back.

I think this is Behotec gear with these kits - Maybe they have some lighter springs for these struts.

I got several more flights on mine at MAB, this jet is insanely neutral. Almost no down elevator required while inverted. Almost no coupling. Flies on rails with no gyro in windy conditions. Once this gear issue is sorted, it'll be perfect!

bluelevel

My Feedback: (39)

I have the Electron retracts in my Leo and not the standard air driven gear (that is made by AirTech btw and not Behotec). I cannot complain about the spring rate of the mains, these are perfectly fine. But the nose wheel being a little bit softer would definitely help the ground handling. Maybe I'll grind the spring down a little or ask the factory, if they have softer springs available to try. But you are absolutely right about the position of the mains, these being back by half an inch would help.

Thomas