The principle which has been found
to be most satisfactory is to fix the points of suspension
distributed over the greatest length of envelope possible
proportional to the lift of gas at each section thus formed.
From these points the wires are led to the car. If the car is
placed close to the envelope it will be seen that the suspensions
of necessity lie at a very flat angle and exert a serious
longitudinal compression. This must be resisted by a high
internal pressure, which demands a stouter fabric for the
envelope and, therefore, increased weight. It follows that the
tendency of the envelope to deform is decreased as the distance
of the car from the gas compartment is increased.
One method of overcoming this difficulty is found by using the
Astra-Torres design. As will be seen from the diagram of the
North Sea airship, the loads are excellently distributed by the
several fans of internal rigging, while external head resistance
is reduced to a minimum, as the car can be slung close underneath
the envelope. Moreover, the direct longitudinal compression due
to the rigging is applied to a point considerably above the axis
of the ship. In a large non-rigid many of these difficulties can
be overcome by distributing the weight into separate cars along
the envelope itself.
Pages:
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31