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<DOCNO>
677
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<TITLE>
methods for calculating the lift distribution of wings /subsonic lifting
surface theory/ .
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<AUTHOR>
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<BIBLIO>
r + m 2884, r.a.e. rep. aero. 2353. a.r.c. 13,439. january 1950 .
</BIBLIO>
<TEXT>
this report contains some fairly simple and economic methods for
calculating the load distribution on wings of any plan form based on
the conceptions of lifting surface theory . the computer work required
is only a small fraction of that of existing methods with comparable
accuracy . this is achieved by a very careful choice of the positions
of pivotal points, by plotting once for all those parts of the downwash
integral which occur frequently and by a consequent application of
approximate integration methods similar to those devised by the author
for lifting line problems .
the basis of the method is to calculate the local lift and pitching
moment at a number of chordwise sections from a set of linear equations
satisfying the downwash conditions at two pivotal points in each
section . interpolation functions of trigonometrical form are used for
spanwise integration both in setting up the downwash equations and in
getting the resultant forces on the wing from the local forces . the
preliminary chordwise integrations for the downwash are predigested in
a series of charts/figs.1-6/,.it is these which make the method a
practical computing proposition .
the theory is outlined in sections 2-5,.section 6 deals with the
solution of the linear equation and section 7 with the resultant forces
on the wing . some examples are worked out in section 8 to compare with
other methods,. one solution is given in full detail in tables 8-30 as a
 guide for computers . appendices i-vi discuss more carefully some
salient points of the mathematical theory, and appendix vii is intended
to instruct the computer how to carry out the steps of the calculation .
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