plated with duralumin sheets and the upper part is covered with
canvas attached to light wooden battens to give the necessary
shape. This effected a very considerable reduction in weight.
The original 250 horse-power Rolls Royce engine was installed,
now driving a single large two-bladed propeller astern. A test
having been taken, it was found that the disposable lift under
standard conditions was 6.28 tons. It was therefore decided that
all the ships of the class should be modified to this design when
circumstances permitted. Speed trials were carried out under
various conditions of running, when it was found that the ship
possessed a speed of 54 1/4 miles per hour with the engines
running full out.

To summarize the performances of these ships as we did in the
case of No. 9, we find:

Speed:
Full 54 miles per hour
Normal =2/3 48 " " "
Cruising =1/3 33 " " "

Endurance:
Full 18 hours = 1,000 miles
Normal 26 " = 1,250 "
Cruising 50 " = 1,900 "


The production of the rigid airship during the war was always
surrounded with a cloak of impenetrable mystery. Few people,
except those employed on their construction or who happened to