ESDU 70011:2012

ESDU 70011 presents data for the lift-curve slope and
aerodynamic centre position for wings with straight leading- and
trailing-edges and streamwise tips in subsonic flow. The data were
derived from lifting-surface theory and are presented in carpet
form for ßA up to 12,
Atan?
_½ up to 6 and taper ratio (?) from 0
to 1, where A is aspect ratio, ß is (1 –
M²)^½ where M is Mach
number, and
?
_½ is the half-chord sweep. The data can be applied to other
than straight-tapered planforms by means of the equivalent wing
planform concept (ESDU 76003 or ESDU 76015). Comparisons with a
wide range of test data indicate that the lift-curve slope of wings
on wing-body combinations is predicted to within about 5% and that
aerodynamic centre position is predicted generally to within 0.03
of the aerodynamic mean chord.

A computer program of the method (ESDUpac A7011) is provided.
The program, which includes an extension to cover wings with
modestly swept forward half-chord lines, can be run online at
esdu.com.

For information, an improved form of the Helmbold-Diederich
equation for wing lift-curve slope is given which provides
predictions largely within ±2% of the values obtained from this
Data Item for ßA > 1.5.