Electric Stunt > Gettin all AMP'ed up!

Power System Setup

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jfv:
I'm putting together an electric adaption of the Flite Streak (my own structural design) and just want to make sure I have the power system spec'd out correctly.  The plane has a full fuse similar to the combat Streak.  I'm estimating the total weight in the high 20 oz range depending on the battery selection.  I have a Scorpion 3014-16, a CC Phoenix 35 ESC, and a Ztron timer.  I'll be running in governor mode.  Based on what I read here, using a 10x7 APC E prop set about 8500 rpm should be a good starting point.  I've also read that a 2100, 3 cell pack would work, but based on my electric RC experience, that seems a little light on capacity.  Comments and recommendations would be appreciated.

Alan Hahn:
What you have is exactly what I am now running in my Super Clown (I just swapped the Brodak Motor for a Scorpion 3014).
I do use the 3s2100mAHr setup and was using about 1700 mAHr last time I looked. Yes it is a little edgy, but since the battery "only" costs ~$47, I'm willing to take some chances! Besides, that was with the Brodak motor--hope I do a little bit better with the Scorpion--but will see!

I am running on 0.012 58 foot lines---AMA "legal". My all up weight is ~28oz (using the 3s2100). My notes say I was flying 4.8s laps at 8400 rpm, with level flying power at ~200watts, peaking to 290 in the verticals. I wanted to increase the lap time by 0.1 sec--it would be a bit more comfortable.

jfv:
Thanks Alan.  I'll go with the 2100 pack since I have a stock of those.  One more question.  What are your flight time settings on your timer?

Alan Hahn:
On my JMP-2 (which is similar to the Ztron 2) I start with a 20 second delay, plenty of time to walkout to the handle. The total flying time is setup to fly 310s. I start a 6 min countdown timer just as I initiate the timing sequence (when the 20 s delay starts). I am coming out of the 4-leaf clover when the timer hits 5 minutes. I get the 2 blip warning about 20s later. I am walking to pickup the plane at 5m50s on the timer. Now this is with the Nobler, but the SuperClown is similar (a little faster actually since the Nobler is flying 5s laps.

One thing I like about the Ztron is that you can disable the 2 blip warning.

Another detail is the slow ramp-up and down of the CC ESC on governor mode takes about ~10s to go from off to on andvice versa.

Throttle wise, I think the timer/throttle is set at about 30% (maybe lower) to get an rpm of 8100. On the Ztron that would be a "15" if my memory is correct. (I'll check that out).[added--my notes tell me a Ztron setting of "16" on the dip switches corresponds to a rpm of 9100rpm, so I'm now guessing a 14 or so will get in the ballpark of 8500 rpm.]

Here is a rundown of the current settings in the CC Phoenix 35.

AutoLipo Detect
Soft Cutoff (Heli gov mode always forces this)          50% Brake [off in Heli Gov mode]
Heli Gov HIGH                                                                 0.6s Brake delayed   [off in Heli Gov mode]
Forward Direction                                                           Brake Immediate  [off in Heli Gov mode]
 Motor Start   Medium                                                     PWM rate 13kHz
Throttle Response   Medium                                         Current Limiting--Insensitive
Motor Timing  Low Advance (to see if it is a bit more efficient)
Governor gain   Custom--71                                         Spool-up speed   Custom  10 [as fast as I can get it]

jfv:
Thanks again for the info.  I'll copy your setup to start with and work from there.  Got back into flying pretty heavy several years ago after a long layoff.  Still scratch build most of my stuff.  All my RC planes are electric.  Really looking forward to getting back on the "lines" as that's where my roots are.  My flying friends always bust my chops because they say all my RC designs look a lot like control line planes.  I'll let you know how things worked out.

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