Here is a copy of an interesting comparison in a book
by Hugh Allen, published in 1931, whose thesis was the natural advantages and
dominance of LTA airships over airplanes. It's an interesting twist on the
usual criticisms hurled at airships. Quotes follow :
".... The airplane is a dynamic craft, deriving
its lifting power from its velocity alone. The air pressure and suction on its
wings give aerodynamic lift only as long as flying speed is maintained.
The airship is primarily aerostatic, that is its
buoyancy arises from the fact that the lifting gas it contains is so much
lighter than air that it will support, without other assistance, not only the
balloon-like cells in which the gas is contained but the metal frame of the
ship itself and the weight of crew, motors, fuel, and a pay load.
The airship continues to remain aloft even though its
motors are shut off.
The airship, however, has an additional buoyancy, an
aerodynamic lift resultant from motors and control surfaces.
[SO FAR, SO GOOD! Then the analysis and predictions
start]
The airship and the airplane differ again in that the
airplane is primarily a fast short distance craft, while the airship is slower
and comes into its full efficiency only on long voyages, particularly across oceans.
The cruising speed of most transport or mail planes
carrying a pay load is 100 to 120 miles an hour with a radius [RANGE] of about
500 miles. Though naturally a specially built or special purpose plane can fly
faster and farther if pay load is replaced by fuel.
The airship, having a speed of 80 miles an hour and
carrying ten tons of useful load, has been flown more than 6,000 miles in 69
hours with a comfortable fuel reserve at the end of the journey.
While the transatlantic flights of the R-34, the Los
Angeles, the Graf Zeppelin and the R-100 have indicated transatlantic flying as
a logical field for the airship, there will still be controversy as to whether
the airplane may not challenge the airship here.
In discussing the subject before a meeting of the
Society of Automotive Engineers in New York in May, 1930, former Commander J.C.
Hunsaker, U.S.N., who had charge for the Navy of the design both of
heavier-than-air craft and lighter-than-air craft during the war [WORLD WAR I]
stated his belief that :
"All successful Atlantic airplane flights may
fairly be discounted as having been made by overloaded planes, without payload,
by abnormally courageous pilots, and in the most favorable summer weather that
could be found. The unsuccessful airplane flights give mute testimony that good luck cannot be
depended on.
"We do know, however," he continued,
"that the modern airplane can fly the Atlantic provided that one of
several things does not happen. The things that must not happen re : first, persistent head winds causing
exhaustion of fuel supply at sea; second, engine failure from any cause; third,
loss of visibility with consequent loss of control and course; and fourth,
failure of any structural part or function of lifting, stabilizing or control
surfaces.
"Each of these contingencies may be fatal to the
airplane, and in this I include the flying boat or seaplane in the North
Atlantic, as its chance of survival there on the surface of the sea is at best
precarious. In low latitudes both in the Pacific and Atlantic, the flying boat
has a very fair chance to remain afloat,
but due to the infrequency of passing steamers many days may elapse
before rescue. In general, a forced landing on the high seas cannot be
tolerated by a commercial enterprise.
The chance of a forced landing at sea due to exhaustion
of fuel is measured by the margin of fuel carried versus the weather to be
expected. We know that even with an overloaded start and no pay load and with
favorable weather there has been practically no margin for those airplanes that
have successfully negotiated the eastward crossing of the North Atlantic.
We are building larger airplanes but their endurance
unfortunately is not increasing... There are gains in aerodynamic and
structural efficiency due to changes in design made possible by very large
airplanes, yet the effect of such gains is largely absorbed in overcoming the
relative weight increase due to size itself."
End of quote from book "The Story of the Airship"
[GEE, DO YOU THINK THAT THE AIRPLANE WILL EVER CATCH UP
TO THE AIRSHIP --- THE EXPERT ENGINEER WHO WROTE THAT LITTLE PIECE IN 1931, QUOTED
VERBATIM ABOVE, ASSURES US THAT IT COULDN'T POSSIBLY HAPPEN but it's certainly
an interesting twist on the usual blather by the negative nattering
anti-airship nabobs. ]
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