i did a dimensional analysis. but I'm pretty sure that I'm using all the right units. still having problems though. are the formulas correct and is the oswald efficency factor an approptriate value for a DC - 10?
the answers that i got using these formulas were:
for Cd = 0.125
for Cdi= 0.0137
for CDo = 0.11
as cdi and cdo were so different i thought that there must be a problem.
i was also unsure if the thrust value given was for one engine or for all three. is it an appropriate value for three...
i am having trouble calculating various drag co-efficents for a dc -10 in cruise.
i have found this data:
Thrust: 153000 lb
density: 0.00085 slug/ft
V= 852ft/s
W=580000lb
AR= 7.5
e= .8
S= 3958ft^2
Cl= 0.5
I have also found the formulas
Cd= D/ (density x S x V^2 /2)
Cd= Cdo +...