Hello,

Just a couple quick comments. I have seen the Osiris fly on a 5S pack at about 1400 watts and it flies very, very well. However, keep in mind that this particular plane was right at 6 lbs or maybe slightly less. I was surprised to see the Wind S50 come in a 7 lbs. I have an Angel and its RTF weight is right at 6 lbs with a 5S 4000 mah pack. My general thinking is that a 5S pack is good for a 5.5-6 lb bird. Any heavier weight would probably require a 6S pack.

Good luck,

Teo