phys_student1
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Lift and Drag...Which frame of reference?
Hi,
When expressing the Lift and Drag acting on an airplane as:
F_{lift}=qSC_L
F_{drag}=qSC_D
where q is the dynamic pressure, S is the wing ref. area, and C's are the lift and drag coefficient.
My question: Some sources, like this one, claim these equations are 'defined' in stability frame {S}, while other claim they are in wind frame {W}. In either case you'll use a rotation matrix to go back to body frame {B}, but this matrix will differ whether going from W->B or S->B, wo which is correct?
Hi,
When expressing the Lift and Drag acting on an airplane as:
F_{lift}=qSC_L
F_{drag}=qSC_D
where q is the dynamic pressure, S is the wing ref. area, and C's are the lift and drag coefficient.
My question: Some sources, like this one, claim these equations are 'defined' in stability frame {S}, while other claim they are in wind frame {W}. In either case you'll use a rotation matrix to go back to body frame {B}, but this matrix will differ whether going from W->B or S->B, wo which is correct?