Spektrum AR7100 Series User Manual page 8

EN
Recommended Guidelines for Battery Capacity
For 50-size electric and glow powered helicopters a minimum capacity
of 2000mAh is recommended. For 90-size helicopters a minimum of
3000mAh is recommended. Our staff uses 2000mAh LiPos in 50-size helis
and 4000mAh LiPos in 90-size machines and typically flies 4 or 5 flights
then recharges.
Following is a picture of a typically recommended installation.
8 Spektrum AR7100