Originally Posted by
issaccph
"When flaps are lowered, lift increases but so does drag. The drag increase is proportionately greater than the lift increase, even at small angles of flap extension, i.e. the L/D ratio is less with flap extended."
I don't get why CD-increase is greater then CL-increase, even with small angles of flap. I have a graph in my book showing that CL increases a lot with 10° flaps and CD increases just a bit with 10° flaps. How come "CD increases proportionately greater than CL"?
Thx!
P.S. I tried to add a picture of the graph but I get an error that I can't add an URL because I don't have 10 posts yet. The admin is not very helpful either...