This article is from the Radio Control (R/C) Flying FAQ, by Shamim Mohamed shamim@math.isu.edu with numerous contributions by others.
Electric power systems are heavier for a given power output. This means
that planes must be built lighter, which may be more challenging
(especially for the beginner). That's really the only significant
disadvantage. The big advantages are that electrics are quiet and clean.
To me, the biggest advantage of all is that electric flight is unusual and
interesting.
 
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