henk

Hey All, I'm thinking of building a spadet-40 off the spad home page. I like the size and look of the plane, but I would like to fly electric. Any recomendations on an elecric set up that would work for this size plane? I would like to get at least 10 min flight time. Any input would be very helpful. Thanks.

H.

Greg Covey

Hi,

If this is the plane you're refering to, then simply copy my AXI 4120/14 setup on my Hobby Lobby Skylark thread in this forum.

You can use the [link=http://PM22002]http://www.hobby-lobby.com/motormt.htm#AXI1[/link] Radial Mount Set without any PVC offset coupler. Additionally, to simplify setup, use the newer [link=http://www.hobby-lobby.com/jetiblue.htm]JESA40[/link] Jeti Advance 40amp controller with built-in BEC up to 16-cells NiCd or 4s LiPo.

Use an APC 14x10 or 15x8 e-prop.

Good luck!

Matt Kirsch

My Feedback: (21)

I'm not familiar with the construction of the SPADet is in general, but you can eliminate a lot of weight by using 2mil Coroplast for the top surface of the wing, and using a folded Coroplast tube instead of gutter pipe for the fuselage. Using these techniques, my Coro-trainer weighs about the same as a standard balsa trainer.

One of my next projects is to fold up a slightly smaller version of my own-design Coro-trainer and put a 400 Watt system on it.

henk

Greg and Matt, thanks for the info. Here's the link to the spadet. H.



http://www.spadtothebone.com/SPAD/Spadet/

espadet

I'm finishing my first electric spadet- 70 % reduced from original plan-. wing span :50 " wing area:400 sq inch and weight: less than 3
pounds. All 2.4 mm coroplast. Instead the gutter pipe I use foam 2 1/4" block (2 pieces).
My power setup is : Trinity Speed Gems 12 turns(ferrite r/c car motor) w/ Master Airscrew gearbox 3:1 ,10x6 prop and 6 or 7 Sanyo Nicd SubC cells.


The only reference that I've is Motocalc :

Gear Ratio = 3.50Diam (in) = 10.0Pitch (in) = 6.0 NC = 6
Weight (oz) = 48.5
Batt Amps = 31.6Motor Amps = 31.6Motor Volts = 6.4
Input (W) = 201.2InPLd (W/lb) = 66.3Loss (W) = 55.4
MGbOut (W) = 145.9OutPLd (W/lb) = 48.1MotGb Ef(%) = 72.5Shaft Ef(%) = 64.1
Motor RPM = 27428Prop RPM = 7836
Thrust (oz) = 30.1PSpd (mph) = 44.5RofC (fpm) = 644
Time (m:s) = 3:13

The static pitch speed (45mph) is within the range of approximately 2.5 to 3 times the model's stall speed (18mph), which is considered ideal for good performance.
With a wing loading of 15.5oz/sq.ft, a model of this size will have trainer-like flying characteristics. It would make an ideal trainer, for use in calm to light wind conditions.
The static thrust (30.1oz) to weight (48.5oz) ratio is 0.62:1, which will result in short take-off runs, and no difficulty taking off from grass surfaces (assuming sufficiently large wheels).
At the best lift-to-drag ratio airspeed, the excess-thrust (14.7oz) to weight (48.5oz) ratio is 0.3:1, which will give strong climbs and rapid acceleration. This model will most likely readily loop from level flight, and have sufficient in-flight thrust for many aerobatic maneuvers.

Any input would be very helpful. Thanks.

espadet

And with 6 Sanyo 2400 Nicd SubC cells, 9x6 prop, 3.5 gearbox:

Weight (oz) = 54.2
Batt Amps = 25.5 Motor Amps = 25.5 Motor Volts = 6.6
Input (W) = 168.5 InPLd (W/lb) = 49.7 Loss (W) = 43.0 MGbOut (W) = 125.5 OutPLd (W/lb) = 37.0
MotGb Ef(%) = 74.5 Shaft Ef(%) = 68.5
Motor RPM = 30022 Prop RPM = 8578
Thrust (oz) = 23.4 PSpd (mph) = 48.7 RofC (fpm) = 409
Time (m:s) = 5:53 and to level flight and throtle 80%: 10 min