n in the
air 96 hours, or four days, without landing.

It is therefore patent that in R 33 and R 34 we possess two airships
which can cross to America to-morrow as far as actual distance is
concerned, but various other conditions are necessary before such
voyages can be undertaken with any prospects of commercial success.

The distance between England and America must be roughly taken as 3,000
miles. It is not reasonable for airship stations to be situated either
in the inaccessible extreme west of Ireland or among the prevailing
fogs of Newfoundland.

Weather conditions must also be taken into account; head winds may
prevail, rendering the forward speed of the ship to be small even with
the engines running full out. In calculations it is considered that
the following assumptions should be made:

1. At least 75 per cent additional petrol to be carried as would
be necessary for the passage in calm air, should unfavourable
weather conditions be met. This amount could be reduced to 50
per cent in future airships with a speed of upwards of 80
miles per hour.

2. About a quarter of the total discharge able lift of the ship
should be in the form of merchandise or passengers to render
the project a reasonable commercial proposition.

We will consider the commercial loads that can be carried by the German
airship L 70 and our airships R 33 and R 38 under the conditions given
above. Two speeds will be taken for the purposes of this comparison:
normal full speed, or about 60 miles per hour, and cruising speed of 45
miles per hour.

L 70.--At 60 miles per hour a distance of 3,000 miles will be
accomplished in 50 hours.

Fuel consumption about
13 tons + 9.75 tons (additional for safety) = 22.75 tons.

Available lift for fuel and freight = 27.8 tons.
Fuel carried = 22.75 "
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Balance for freight = 5 " about.
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At 45 miles per hour, distance will be
accomplished in 66.6 hours.

Fuel consumption about
10 tons + 7.5 tons additional = 17.5 tons.

Available lift = 27.8 tons
Fuel carried = 17.5 "
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Balance for freight