Aermacchi MB-339 Scratchbuild EDF

by AeroErgo | November 24, 2018 | (6) Posted in Projects

Hello guys/gals!

                              Here i am again with another project, this is a plane for a friend who ask me to build an Aermacchi MB-339 A rc plane for him, i didn´t see any commercial kit at small size like this so i say "challenge accepted" . 

As usual don´t use any plans, or computer design. Just because it´s my way of building planes. I still have an EDF like the one i use on the A-4 Skyhawk  so the idea was make a plane little bit longer to take advantage of the greater span of the italian plane, also, i wanted to try make a plane with all the tricks and tips that i used before in other planes. The intake ducts where a real challenge, ´cause the original aircraft has very small ones, and built-in the wing roots, so i had to put them out of scale to reach enough amount of air flow for the EDF unit. Anyway, as i just have 3S batteries and the trust will not be as high as i wish.

Let´s get some Specs:

Lengh: 830mm

Wingspan: 930mm (with tanks)

Weight: 570grs (On flight conditions)

Engine: 55mm EDF 4200kv aluminium case from HK (4S Version)

ESC: 30A HK ESC.

Battery: 3S 1300mah 75C TATTU.

The build:

First i was drawing the Aermacchi for days before i start to make real size draws so i could put all the pieces of the plane, the electronics and reinforcements togheter in my head.

Once i have a real size draw i built it up from there:


My friend suggest add a landing gear in the future, so i left some balsa/plywood hardpoints inside the wing and nose:

With pacience and calm the plane begin to take his shape:

Nose cone made from a soft foam core, shaped by cutters and sand paper, as the wing tip tanks:

I made some stickers as the Argentinian Navy Aermacchi paint scheme. You can see here also how to cover the top of the plane.

I made this to put inside a plastic PET bottle and get a shinny canopy:

Almost done!

Ailerons pushrods above the wing to prevent some damage on landings and ventral fins made in hard balsa so it could bellylandig with ease:


At this point i choose to make the MAIDEN FLIGHT, so if i have to fix something i will not ruin the paint:



After that hard flight i realize when the C.G. is correct and the plane make strange movements the problem must be the incidence, so i make some modifications to the horizontal stabilizer and try again:




Now it flies great !!!! Let´s make it look cooler drawing some lines with black marker:


And the most important part, the paint job:

I use foam safe acrilic paint and some tips from FliteTest videos: 


And some stickers of Argentinian Navy, as the plane piloted by Owen Crippa in 1982:

I hope you like and find the pics useful. Sorry for my bad english, i try to do the best i could. Happy flights!!!!



COMMENTS

paracodespoder on April 2, 2019
Nice work! That looks amazing,and without any plans?! Fantastic!
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AeroErgo on April 2, 2019
Thanks!, yeah, i don´t use plans, just few draws to guide me on the build.
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FoamyDM on April 3, 2019
It's a shame, there are a number of folks here who would LOVE to take a stab at it here too.
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AeroErgo on April 5, 2019
Yeah, but i don´t make all the parts in a CAD software so usually i can´t reply the same plane again, like a serial production. Just a craftman work every time. I think sometimes a serial production will handicap the scale of the model. But if some day i use CAD i will upload the plans of course. :)

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Jackson T on April 2, 2019
That is one REALLY cool scratch build jet!
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AeroErgo on April 2, 2019
Thanks!, yeah, srcrathbuild is the only way here ! it´s too expensive buy some RTF...

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erad on April 2, 2019
Absolutely great build man!!!
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AeroErgo on April 5, 2019
Thanks! :)
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Gryf on April 2, 2019
Excellent work! It looks great and flies perfectly.
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AeroErgo on April 5, 2019
Thank you. Yes she flies great now, like a trainer ! But in the first flight the wind and the horizontal stabilizer incidence make it bumpy in the air. After fix both things it flies perfect!
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njacobs on April 6, 2019
Lovely build. Well done. I agree, scratch building gives one a huge amount of satisfaction seeing your own creation fly, and fly well. Nice canopy - how did you make the canopy out of a pet bottle over the foam ?
Don't worry about your English it was well written, anyway, its way better than my Italian ;)
Cheers, Nicholas
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AeroErgo on April 12, 2019
Oh thanks! i use a mockup of the canopy and later i heat it up with a hot air gun until take the shape of the matrix. Maybe i should make a video of it.
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MiniacRC on April 8, 2019
Amazing work! The craftsmanship is top notch and the landing on the first flight was so enjoyable! :)
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AeroErgo on April 12, 2019
haha, well, was so windy that the plane land vertically !

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Aermacchi MB-339 Scratchbuild EDF