The calculator is a device in slide rule form for assisting in the design and stressing of flat rectangular panels in shear.

In the Incomplete Tension Field theory, the ratio q/qb becomes an important factor, where

q applied shear stress (lb./in.2)

qb shear stress at which panel first buckles (lb./in.2).

This ratio is normally evaluated by use of the formula

qb = KE(t/b)2

where E Young's modulus (lb./in.2)

t thickness of panel (in.)

a length of longer side of panel (in.)

b length of shorter side of panel (in.)

and K depends on the value of b/a and the edge conditions, and is normally obtained from R.Ae.S. Data Sheet 02.03.01.

This method becomes laborious when dealing with large numbers of panels.

By the use of the Calculator, q/qb may be found quickly, with no unnecessary paper work.