achine."

CHAPTER VII. PUTTING ON THE RUDDER.

Gliders as a rule have only one rudder, and this is in the rear. It
tends to keep the apparatus with its head to the wind. Unlike the rudder
on a boat it is fixed and immovable. The real motor-propelled flying
machine, generally has both front and rear rudders manipulated by wire
cables at the will of the operator.

Allowing that the amateur has become reasonably expert in the
manipulation of the glider he should, before constructing an actual
flying machine, equip his glider with a rudder.

Cross Pieces for Rudder Beam.

To do this he should begin by putting in a cross piece, 2 feet long by
1/4 x 3/4 inches between the center struts, in the lower plane. This may
be fastened to the struts with bolts or braces. The former method is
preferable. On this cross piece, and on the rear frame of the plane
itself, the rudder beam is clamped and bolted. This rudder beam is 8
feet 11 inches long. Having put these in place duplicate them in exactly
the same manner and dimensions from the upper frame The cross pieces on
which the ends of the rudder beams are clamped should be placed about
one foot in advance of the rear frame beam.

The Rudder Itself.

The next step is to construct the rudder itself. This consists of two
sections, one horizontal, the other vertical. The latter keeps
the aeroplane headed into the wind, while the former keeps it
steady--preserves the equilibrium.

The rudder beams form the top and bottom frames of the vertical rudder.
To these are bolted and clamped two upright pieces, 3 feet, 10 inches
in length, and 3/4 inch in cross section. These latter pieces are placed
about two feet apart. This completes the framework of the vertical
rudder. See next page (59).

For the horizontal rudder you will require two strips 6 feet long, and
four 2 feet long. Find the exact center of the upright pieces on the
vertical rudder, and at this spot fasten with bolts the long pieces of
the horizontal, placing them on the outside of the vertical strips. Next
join the ends of the horizontal strips with the 2-foot pieces, using
small screws and corner braces. This done you will have two of the
2-foot pieces left. These go in the center of the horizontal frame,
"straddling" the vertical strips, as shown in the illustration.

The framework is to be covered with cloth in the same manner as the
planes. For this about ten yards will be needed.

Strengthening the Rudder.