On my 4c pack I fast charge at 4.9... I lost a plane once due to
the battery... If I can help it.... Never again!!! Tranny, once my
meter shows mid scale, I never really looked at the voltage...
I do carry an extra battery for my tranny, So I just switch it
out and slow charge at home... A few members have said you
can get a few more flights out of that, I say for the amount of
time it takes to fast charge, or chance losing the plane... I'll
go the fast charge route....