Thread Tools
Jul 26, 2002, 07:27 PM
Registered User
e-sailpilot86's Avatar
Question

Well performing long chord-ed flying wing, how is it possible?


I've seen two flying wings at my club, and they fly wonderfully! The wingspan must be 60-80 inches, with a chord of maybe 30-35 inches! How do they fly so well? It's as if they're some type of high aspect ratio high L/D ship... Does anyone know of any plane like this, and why they do so well?
Sign up now
to remove ads between posts
Jul 26, 2002, 08:49 PM
Registered User

Low Aspect Ratio Wing


At the best L/D half the drag of any gliding plane will be induced drag. At speeds between stall and best L/D the induced drag is more than half the total drag. The induced drag is proportional to the square of the coefficient of lift and inversely proportional to the aspect ratio. This suggests that there are two ways to reduce induced drag. The conventional approach is to increase the aspect ratio associated with a high lift airfoil. The second way is to use a very low coefficient of lift. The wing loading must be drastically lowered to have a similar speed envelope to the high aspect ratio case. I'll bet that these flying wings have very thin airfoils and wing loadings around 3 ounces per square foot or less.

I would very much like to see pictures or drawings and know the airfoil used.