ORIGINAL: jerzdvt
-Does more mah mean longer flight time?
Yes, the mAh rating is the battery capacity or "fuel tank" size.
-Can you interchange Nimh, Nicad, and Lipo? (which is better, Nimh or Nicad)?
I'm not exactly an expert on electrics but I imagine that would depend on the ESC. I know some work with various types of batteries and some don't. maybe someone else can elaborate on that. As far as which is better, that depends on application. Nicads can provide a lot of power quickly and are very cost effective but require regular cycling while NiMh has higher capacity than NiCad given the same physical size but some may not be able to deliver it as quickly. Everything has good and bad qualities and everything has areas where it works well.
-Is there any way to obtain 10-15min flight times with an electric trainer?
I don't see why not if you have a fairly high capacity battery and manage the throttle.
-Does it really take an hour to charge a battery when the advertisement says 15min?
Again, I'm no expert but I'd be careful about charging batteries too fast. To do it means more current being pushed into the battery, resulting in more heat. From what I understand, 1C is the fastest you want to charge most batteries. (1C=1xrated capacity. For a 1000mAh battery, 1C would equal 1000ma or 1A). This should theoretically give a charge time in the 1 hour range. I could be wrong about this however, maybe someone else can elaborate.
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