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Old 01-06-2010, 11:27 PM
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can773
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Default RE: 30C Batteries for F3A

Hi Jean-Paul,

In F3A one of the more important aspects of a battery is the energy density (Wh/kg), we need lightweight, sufficient flight time, total power is not the most important things. C rating does not affect this parameter directly, however higher C batteries are in general heavier which lowers their energy density.

The original Prolite batteries from TP were some of the highest energy density packs produced (the 2000 mAh cell was very high for a lipo), and is the main reason why they worked so well for pattern.

A side benefit of lower C packs is they act as a governor of sorts. In order to get 9 minute flights you have roughly a 7C average discharge rate, with maybe double that as a peak burst on uplines. A 20C rated pack discharging at 7C average cannot burst as high as a 30 or 40C rated pack can. In a lipo the closer you operate to the rated discharge capacity, the less burst capability you have. This is why a lower C pack feels much more consistent in flight. Again this is why the original Prolites which were 13-15C packs felt so consistent because while operating at 7C average they could not produce a large burst of power like some of the modern packs can.

High C packs are good for guys who want to fly for two-three minutes

Hope that helps