Multiplex Twinjet becomes MonoJet and flies MUCH better with less power needed !!!
Conversion
to a single motor is extremely easy. The motor & esc are in direct line with
the central fuselage. So no long wires or tunnels needed. It can be clearly seen
in the construction photos.
Batteries
8-10
cells.
Motor
kontronik
501 packages. It consists of the fun 480-33 motor with a 4.2 gearbox.
Possible Motor combinations for the Monojet
Note: "good" - our
reference point. "good" is the way
the Monojet flies with the kontronik 501, 8x1700CP, 11x12.75 prop. performance
can be seen in the video. naturally, "good"
is much better than the regular stock Twinjet...
Propeller
I
tried several folders. It must be folders to prevent prop breaking every
landing.
The
basic prop is a 11x10 (Aeronaut), this is the highest pitched prop I could find.
I added a "twisted yoke" with 2.5 degrees and it became 11x11.4.
2 videos taken with this setup and 8 and 10 cells.
This one gave the best performance even with "only" 8 cells. It has an
amazing climb ability and excellent speed.2 Videos taken with this setup
Power consumption
This power set-up draws about 27 amp (motocalc predicts 28 amp - good work motocalc !! ).
Flight Test results
I did
not try this arrangement with 10 cells yet, but it should be a beast!! 8x1700CP
produce amazing performance.
I was a
little worried before the test flight because of two things: torque roll right
after hand launch & injuring the arm by the large centered prop. I was
worried for nothing. The prop stays away quite a bit from the launcher arm, so
no problem here. Even with all the torque, I only needed 2-3 clicks of right
trim to make it fly straight as an arrow!
The
Monojet has a different sound than the original/twin-powered set-ups, less
noisy, a lower sound.
Climb
out at 60 degrees forever with excellent speed. With 10 cells it should go
vertical with amazing speed and still only draw around 36amp. Landings are easy
(like in all twinjets) with the large blades folding neatly at touchdown. One
thing in flight is different and that is the rolls. If you think twinjet's rolls
are fast, you must check out the Monojet's rolls, about twice as fast (due to
the centered prop I suppose). It was a pleasant surprise.
We
tested the Monojet side by side with Patrick's brushless Twinjet (kontronik
twin drive), both planes operated by 8x1700CP. Monojet was a little faster and
had a better rate of climb (watch the video of this test).
Feel free to contact me with any questions regarding building or anything else. Most important, if you need any advice in choosing a suitable power set-up, I can help here as I became a real "motocalc expert" in these Monojet different power systems.
My Email: odedmaz@inter.net.il
Oded Mazor and his Multiplex "MonoJet"
See
videos of the test flights with the 2 different prop setup here