actice
adopted by the Schutte-Lanz Company in Germany.

It must be frankly acknowledged that this experiment resulted in
failure. The ship when completed showed great improvement both in
shape, speed and lifting capacity over any airship commissioned in this
country, and as a whole the workmanship exhibited in her construction
was exquisite. Unfortunately, under the conditions to which it was
subjected, the hull structure did not prove durable, and to those
conditions the failure is attributed. Under different circumstances it
may be hoped that the second ship, when completed, will prove more
fortunate.

In length R 31 was 615 feet, with a diameter of 66 feet, and the
capacity was 1 1/2 million cubic feet.

In shape the hull was similar to the later types of Zeppelin, having a
rounded bow and a long, tapering stern. The longitudinal and transverse
frames were composed of girders built up of three-ply wood, the whole
structure being braced in the usual manner with wire bracings. It had
been found in practice with rigid airships that, if for any reason one
gasbag becomes much less inflated than those adjacent to it, there is
considerable pressure having the effect of forcing the radial wires of
the transverse frames towards the empty bag. The tension resulting in
these wires may produce very serious compressive strain in the members
of the transverse frames, and to counteract this action an axial wire
is led along the axis of the ship and secured to the centre point of
the radial wiring. This method, now current practice in rigid airship
construction, was introduced for the first time in this ship.

As will be seen from the photograph, the control and navigating
compartment of the ship is contained in the hull, the cars in each case
being merely small engine rooms. These small cars were beautifully
made of wood of a shape to afford the least resistance to the air, and
in number were five, each housing a single 250 horse-power Rolls Royce
engine driving a single fixed propeller. Here we see another decided
departure from our previous methods of rigid airship construction, in
that for the first time swivelling propellers were abandoned. R 31
when completed carried out her trials, and it was evident that she was
much faster than previous ships. The trials were on the whole
satisfactory and, except for a few minor accidents to the hull
framework and fins, nothing untoward occurred.

At a later date the whole shi