acdii

I have this plane with twin Power 25 motors. Flew it a few times using 3300 MAH 3S Lipos. Duration seems to be short as my voltage alarm beeps rather quickly at full throttle, but at half throttle it has longer duration, but I dont know how long it will stay up. When I flew a T-34 with the power 25 setup and same packs, got about 8 minutes.

There appears to be plenty of room for larger packs, so do I go with a 3S higher mah, or a 4S of the same or higher mah? I would like to get at least 12 -15 minutes flight time with some reserve.

Walt Thyng

My Feedback: (9)

Duration is a function of amp draw; if you want more duration either install packs with a higher MAH rating or reduce amp draw (as you do when reducing throttle). Going to a 4S pack of the same mah rating will most likely reduce duration (it will also give you more power).
Walt

acdii

Ahh OK, so it will be better to go to a 3S 5000 MAH than a 3500 mah 4S. Good, that I can do without a lot of cash put out.  I dont need the power, with the TO and its flat straight wing, it aint a speed demon, so more power would be a waste, especially since it will take off with 3/4 stick or less.   Depending on the weather tonight, if its decent I will put it up and see how long it lasts at 1/2 throttle, if I can ever figure out these danged timer settings on the JR 12 radio. <div>
</div><div>I tried to setup dual elevator and totally messed up the settings on another plane I was working on.  Sometimes what they have in the manual, and what is on the screen are totally not the same IYKWIM. </div>

flyinwalenda

My Feedback: (5)

Going with a higher mah rating will provide you with longer run times(similar to putting in a larger fuel tank). Your "C" rating determines how much of that power you can use at full throttle without battery damage.
Also , don't run your batteries down to the point where the ESC cuts out to figure out how long you can fly as that will damage the packs . It would be better if you flew the plane for 5 minutes with fully charged packs at full throttle then land and put the packs on your charger or tester to determine how much power was used or how much you have left(It depends on what kind of charger or tester you have)/ Then you have a better idea how long you can fly ad where to set your timer. If you determine you can fly for 8 minutes then set your timer for 7.45.

acdii

I used a voltage alarm that beeps like a madman when it reaches a set voltage on any cell. I set it to 3.4 volts, and it has served me well. The T-34 had the Same power setup in it and I would get 8 minutes before I had to land it.  The 3.4 volts is just a .1 above cutoff on the ESC.