rainedave

My Feedback: (1)

I've attached a pic of the root airfoil from Kimbro's Deception. I was hoping someone might know what type it is. It sort of looks like a laminar flow type since the thickest point is pretty far back. What would its advantages be over an NACA 00xx type? Less drag, I'm guessing.

wellss

probably a 63 series. Drag is only lower in a small angle of attack range. Outside of that range, it is significantly higher, contributing to a lower maximum lift.
At low Rn, the drag reduction is negligable.

Jim_Purcha

My Feedback: (8)

Hey Rainedav, it looks more like a narrow arch support, size 11 or 12 Wing Tip. LOL

BMatthews

It does look like that doesn't it. This sort of shape used to be quite common in pattern ship plans I looked at back in the 70's and 80's. Pappy Debolt in particular was fond of this shape.

At our model sizes it doesn't really work well at reducing drag because it's actually very hard to maintain a proper laminar flow at our typical reynolds number range. What may actually be happening is that the extra drag from the "bad" airflow helps the model to achieve a better constant speed in the verticals. Oddly enough a direct opposite goal to what the airfoil was originally intended for if it really is one of the laminar flow types.

Perhaps Dick Hanson will drop in here and expound more on this since he's probably forgotten more about pattern ships than I've ever known.