I allways wanted to have a A4 Skyhawk jet, but here in my country sometimes become too much expensive. Solution: Make your own EDF JET!
The challenge was have a good performance with just a 3S battery 25c rate of 1300mAh on a 55mm EDF that i can put my hands on, so the weight a become very important issue, so the construction was around the engine and the main part is the wing, all in one piece and the plane build it on it:
No CF rods on it, let´s keep it frugal :P
Later i put the EDF with a plastic film around it, 10% smaller on the rear:
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Tail surfaces are just glued to the plastic film, not very stronger now but it will be with the side foams:
Here you can see the location of the ESC, just in front of the engine intake so get cool air frm the conduit:
Later i make a simple cockpit a nose cone and the intake sides on depron 3mm (on the final version i use 5 mm depron with better results)
Here you can see what the intakes are made of: Raid/Deodorant caps.
Now is ready to the maiden!! :
By the way, someone else experienced the "Dutch Roll" turbulence? I saw it on this plane mostly when i have crosswind. I hope the guys of FliteTest make more videos about aerodynamics issues.
But thumbs ups after all:
High speed landings!!!!! ouchh
Second flight: Now with some flaperon set to make it slower at landings
And some nice snapshot to make you forget the fact this is a model:
Specs:
Lengh: 730mm
Wingspan: 610mm
Weight: 490grs (On flight conditions)
Engine: 55mm EDF 4200kv aluminium case from HK (4S Version)
ESC: 30A HK ESC.
Battery: 3S 1300mah 25C Dualsky ECO
Flight time: 3:30 aprox.
After the first day of tests i decide make a new nose, more "scale" and a little transparent canopy with cockpit, some panels and seat.
I also make the vertical tail wider with a piece of light cartoon board to help with the "dutch roll"
Some paint job:
I don´t use plans, as ussually, (i know my mistake) ´cause i use to just draw the plane on the paper i will use as layout. Just i try to keep the plane proportional to the real one. Actually the fuel tanks make it slower and shaky, but looks great with them.
One of my own demands was be a hand launched plane, nothing of catapults!
Here you can appreciate the increased wing area to reduce the wing load and the cheat holes to increase the airflow to the EDF unit.
And the last video with the final configuration:
The dutch roll still going on, mostly after i put the fuel tanks, but they looks so cool that i decide leave them on, after all they are very usefull to landing safe.
The high speed low level pass is his speciality:
I can say is totally posible make a EDF with small engine and small battery and get good results. A MUST on this plane was the "cheat holes" to increase the airflow, many of my field mates thought the plane just cannot flies on 3S, but it works! Keep it light as possible is allways a good tip.
Maybe next time i will add a rudder.... i miss the control on that situations when i flight close to the ground at high speed and i get a crosswind on the path and if i had a hard runaway, a landing gear, but maybe the weight will be too much for it.
Thanks a lot for read all this and sorry for my bad english.
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