Aircraft Zero-lift Drag Coefficient at Take-off with Gear Up

The aircraft drag polar is expressed as:

..\Images\IMG00030_shg.gif

For parabolic drag polars:

..\Images\INFO0276_wmf.gif

for parabolic drag polars:

..\Images\INFO0277_wmf.gif

where:

..\Images\INFO0278_wmf.gif

is the wing aspect ratio.

..\Images\INFO0279_wmf.gif

is the Oswald's efficiency factor.