SpeedFreak 6 prototype design for its upcoming big brotherSpeedFreak 6 prototype design for its upcoming big brother
Aug 30 2018
It's been a few years since the SpeedFreak has had a revival and on the last version v4 (ignoring the v5 mini which I destroyed before I could write anything about it..) was over 580g AUW which for a 60cm wingspan model is a fat bird. This time the objective was simple:

Bring the design back to basics, massively reduce the weight and this time skip a rudder installation. Given the design is still prototype stage this is just a precursor to its bigger brother already in design.

This model is just 50cm long and has a 50cm wingspan, its RTF minus lipo battery weight is only 181g and with battery (950mAh 2S 45-90c) is exactly 250g AUW. I've been able to reduce the weight compared to version 4 by over 50% while the second generation of this version 6 design is going to push the boat even further.
For this model strength was key especially for landings (or even crashes) so a 3mm solid balsa bottom of the fuselage was called for. The tail and all other fuselage are also balsa.
With the vertical fin in place and aligned it was critical to see the weight given the reduced front end weight means any gram extra on the tail is exaggerated greatly effecting centre of gravity.
The wing is to be cut from a single piece of 6mm balsa with the aileron servos inline for no torque loss. I'm using 11g metal gear Corono servos with 4.8 KG/CM torque.
The wing profile called for a swept wing with a thin profile for speed. It does mean any "gliding" is also at speed.
A side view of the profile being used.
Once the wing was complete it was bonded to the fuselage on all contact sides.
Now to fit the radio receiver and the elevator servo.
The rear top panel on the fuselage is now installed but is removable (by cutting the covering film) if I need access for repairs.
I choose my favourite British racing green colour for solarfilm covering and got to work!
Of course we need tags and now the motor and ESC are both fitted.
One of the prototype ideas was to dump ESC heat generated directly out of the model by exposing the ESC heat sink. This turned out to work very well.
The remaining top panel is to be pinned in place on the front and sliding hinges on the back. On top of that I will be using some tape prior flight as a last backup method having experienced what it's like to lose your canopy cover at over 150mph...
I had some vinyl stickers cut out at work for some stylish decoration.
With the top panel in place the model looks super sleek.
Along side the recently designed field box ready to go for its first ever flight
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