verall height of the ship was
increased by practically 10 feet without the War Office being informed.
The ship flew over and was landed safely, but on being taken into the
shed the envelope caught on the roof girders, owing to lack of
headroom, and was ripped from end to end. The Government agreed to
increase the height of the shed and the firm to rebuild the ship. This
was completed in March, 1911, and the ship was inflated again. On
carrying out a trial flight, having made several circuits at 600 feet,
she attempted to land, but collided with a house and was completely
wrecked. This was the end of a most unfortunate ship, and her loss was
not regretted.

DELTA

Towards the end Of 1910 the design was commenced of the ship to be
known as the Delta, and in 1911 the work was put in hand. The first
envelope was made of waterproofed silk. This proved a failure, as
whenever the envelope was put up to pressure it invariably burst.
Experiments were continued, but no good resulting, the idea was
abandoned and a rubber-proofed fabric envelope was constructed of
173,000 cubic feet volume. This ship was inflated in 1912. The first
idea was to make the ship a semi-rigid by lacing two flat girders to
the sides of the envelope to take the weight of the car. This idea had
to be abandoned, as in practice, when the weight of the car was
applied, the girders buckled. The ship was then rigged as a non-rigid.
A novelty was introduced by attaching a rudder flap to the top
stabilizing fin, but as it worked somewhat stiffly it was later on
removed. This ship took part in the manoeuvres of 1912 and carried out
several flights. She proved to be exceedingly fast, being capable of a
speed of 44 miles per hour. In 1913 she was completely re-rigged and
exhibited at the Aero Show, but the re-designed rigging revealed
various faults and it was not until late in the year that she carried
out her flight trials. Two rather interesting experiments were made
during these flights. In one a parachute descent was successfully
accomplished; and in another the equivalent weight of a man was picked
up from the ground without assistance or landing the ship.

ETA

The Eta was somewhat smaller than the Delta, containing only 118,000
cubic feet of hydrogen, and was first inflated in 1913. The envelope
was composed of rubber-proofed fabric and a long tapering car was
suspended, this being in the nature of a compromise between the short
car of