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-   -   Great Planes Big Stick 40 (http://www.rcuniverse.com/forum/glow-electric-conversions-132/1264820-great-planes-big-stick-40-a.html)

d_wheel 11-09-2003 09:42 PM

Great Planes Big Stick 40
I just put 2 flights on my Stick after converting it to electric. It is the standard 59" span "traditional" Ugly Stick. It had approximately 150 flights as a glow powered model, using an O.S. 52 4 stroke. Having flown Sitcks for more years than I care to admit, it is one of my favorites. I find it very relaxing to fly. Kind of a no brainer type model with no bad habits.

I wanted to keep it as close to stock as possible which meant not using a high gear reduction which would have made it necessary to use a larger propeller. This in turn would have made it necessary to increase landing gear lengths. My final choice was to use a Mega 22-20-2 motor with 3:1 gear reduction and the same 12.25x3.75 prop I used on the 4 stroke. I used the same motor mount that the 4 stroke was mounted to, only having to file away a small amount of material to make the clam-shell mounts fit between them. Battery power for the test flights was 12 cell 3000 mah NiMh. All up weight with this setup is 6 punds 9 ounces. With the 4 stroke it was an even 6 pounds. Calculations provided by P-Calc at http://brantuas.com/ezcalc/dma.asp proved to be pretty much on the money.

The takeoff roll was as expected with solid climb out. Definitely not a "vertical take off" machine, but no problem climbing to pattern altitude. I had forgotten to take a phillips screwdriver with me, so couldn't attach the fuel tank, now battery, cover so didn't try any negative G maneuvers (didn't want the battery pack to fall out). Loops, rolls, etc. were no problem at all. The CG was about 1.5 inches forward from it's glow powered days so it was necessary to fly with quite a bit of up trim. The airplane didn't seem to notice this at all until I tried to do a spin. It just spiraled down with no sign of spinning. Landings were just as solid as ever with nose high touchdowns being very easy.

With throttle management, I got 6 minutes out of each flight. Both flights included full power takeoffs, loops, rolls, and quite a few touch and goes. Except for climb outs, loops, and rolls, I was almost always at 1/2 throttle.

All in all, I am very pleased with this conversion. I will now start looking for ways to lighten the model and will be using a 4S4P 8000 mah LiPo battery in the future. The battery will lighten the model by about 5 ounces and should move he CG back a bit.

I have always recommended the Ugly Stick as a trainer, and will not hesitate to do so with the E-powered version.



jboy381-RCU 12-07-2003 09:48 AM

RE: Great Planes Big Stick 40
sent you a PM...


jboy381-RCU 12-07-2003 10:39 AM

RE: Great Planes Big Stick 40

i was worndering if you wanted to build one from plans???i have two verson of the ugly i got from RCM mag...(das ugly stik and das little stik)the little stik is a 25% reduction of the ugly stik...
PM me if you are intrested...


d_wheel 12-13-2003 12:10 PM

RE: Great Planes Big Stick 40 - Update
Since posting the original message, I have made a few changes to the Stik. First, I switched to 6:1 gear ratio. The original prop has been replaced with an 11x9, and the battery pack is now a 5S4P 8000 mah Thunderpower LiPo. The pack is about the same weight as the original NiMh's, but offer almost 3 times the capacity and about 4 more volts. Flight times, with throttle management, are about 35 minutes per charge. I usually fly 11 or 12 minute flights, and get 3 flights per charge. The first 4 or 5 minutes from a fresh charge yields performance that is better than the original 52-4 stroke glow engine. From that point it is about the same or slightly less. I had to add 6 ounces of lead to the tail to get the CG correct. With the improved performance I am now totally pleased with this conversion.

I have also tried a 14x10 prop, and the performance is more than great! It is unbelievable! Vertical is almost unlimited, and loops/hammerheads, and other vertical maneuvers are close to perfection. Flight times are a little over 25 minutes per charge with throttle management.

The only problems I have noticed is that the larger propeller causes the torque/gyroscopic effects to be worse. During a large loop I have to hold right rudder to keep the track straight. Also, prop clearance on the ground is marginal, but I fly off a paved runway so this is not really a problem.



jboy381-RCU 12-13-2003 11:42 PM

RE: Great Planes Big Stick 40 - Update
great d wheel,

i like to hear about your success...if i want to do mine i know just how to do it...

thanks for the info...


BTW...i sent the plans today should be sent out monday...

dem 06-01-2012 05:32 AM

RE: Great Planes Big Stick 40
I just got a big stick 40 and will be making it an electric from the git go. I am using a Turnigy 420 Kv "G46" motor, a Turnigy 60A controller and planning on using 4000 4cell, 14.8 volt Lipo battery. These seem to fall well within the specs for the conversion. My biggest concerns are:
1. Should the motor be mounted directly to the firewall using the supplied hardware or is there an angle needed to be added?
2. How and where should I be adding holes to allow enough air through the plane to cool the esc?
3. Do you convert to a tail dragger or change wheel size for grass runway?

I have a watt meter and the suggested prop (not near me and do not remember type so feel free to suggest) but not sure of what else I need to be asking. This is my first ARF and also first conversion and want to make my "second" plane as good as possible.

Marcio Senger 07-05-2012 02:34 PM

RE: Great Planes Big Stick 40

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