Originally Posted by Model Aero
Can you share what motor you are using? The 2810-9 motor on 4S pulls about 420 watts with an 8 x 4 prop.
I wish I had the motor info, but I think it's a Grim Reaper of some sort. I bought it at the 3DHS closeout sale a while back. I think the kV must be lower than your 2810-9 motor because it only pulled 415 watts with the 8x6 on 4-cells. It weighs 75 grams so it should work I think.
I was concerned that here in Texas in the summertime, I might need some extra motor cooling. I see the openings in the front of the cowl, but there doesn't seem to be any opening for the air to exit the cowl area. I was planning to cut out an area on the bottom of cowl to provide an air exit and also allow any ingested water a way to drain out.
I have discovered that just like so many other foamies, the Ultra's paint is a little fragile. I tried using the low tack Blue painters tape when I was installing the canopy, but it still pulled off some of the paint. I think that it's just a fact of life that foam doesn't allow much of a purchase for paint to adhere to its surface. It's not a disaster, it's just a reality with foam ARFs.
I hope that my comments are not misinterpreted. They are all intended to be constructive and I hope they can help other builders. I really like my new Ultra and I can't wait to get her airborne!