Improvements in the Art of Aërostation, and Apparatus employed therefor.
Year: 1894

page_text: Date of Application, 21st Apr., 1894-Accepted, 25th May, 1894
COMPLETE SPECIFICATION.
Improvements in the Art of Aërostation, and Apparatus employed
therefor.
I, JOSEPH HOFMANN of No. 1 Lichterfelderstrasse in the City of Berlin
Prussia in the Empire of Germany, Counsellor of the Government, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
My said invention relates to a new system of aërial navigation and to machinery
for carrying into practice the said new system.
Dynamical aerostation, if motive power supplied by animals is not considered,
hitherto has been obtained only by two kinds of mechanical means or machinery,
namely, by rockets, as employed in fire-works, and by toys with screw-propellor-
wheel. In devices of the former class, the capability of flying is only obtained by
re-action (the pressure of gases discharging into the surrounding air in an opposite
direction to the motion of the rocket) and in devices of the latter kind only by
action (the pressure of working surfaces acting on the surrounding air).
These two kinds of mechanical means are scarcely capable of being developed
to ultimate success; the latter kind for the reason that it is practically impossible
to carry the weight of its source of motive power, and the former kind, because its
source of driving power is too rapidly spent.
The same difficulties which exist with the screw wheels, equally exist with other
mechanical means of similar kind, such as flapping wings, wheels with moving
blades, propellors which act by repulsion, like an umbrella closed and opened in
quick succession, and other devices. All kinds of machinery of such and similar
systems are objectionable for the reason that they require engines and steam-boilers,
or explosive-engines, or motors of considerable weight to supply the necessary
power, and further, that, the medium being the atmosphere, surfaces of large
extent are required, which, in their turn, require extensive construction to obtain
sufficient stability.
The object of my present invention is to establish a new system of aërial
navigation, and to construct machinery to carry said system into practical use, in
which system and machinery no working-mechanism is required at all to perform
the operation of flying.
By means of the so-called sailing-flight, generally employed by birds and other
flying animals, it is possible to fly almost in horizontal line to considerable distances,
by cautiously using gravity. But as the atmosphere cannot be traversed without
friction, the loss of elevation, while sailing, will be increased, as the supply of
outside force is reduced, that is, as the wind calms. If the wind be calm or the
atmosphere but slightly agitated, it is only the loss of elevation in sailing that
must be replaced by the animal force. A bird, when sailing, may be well
compared with a sailor at sea, who only occasionally requires steam-power.
For such exceptional use the dead weight of engines of any kind whatsoever is
excessive.
The object of the new system of my invention is to realise the sailing-flight,
independent of the existing greater or minor agitation of the atmosphere, by
replacing the loss of elevation by aspiration of the atmosphere existing above the
surface of resistance, and by forcing it down upon the atmosphere existing below
the said surface of resistance, and, in addition, by making the atmosphere,
forced from the upper down to the lower surface, follow such directions that

page_text: at any time there will remain vertical components and, accordingly, a lifting
power. This tendency may be further increased by mixing with the atmosphere
on its way down from the upper to the lower side of the surface of resistance,
the exhaust steam and the products of combustion, whereby the atmosphere forced
down by aspiration, is caused to expand and its lifting power increased. While
being blown off, the atmosphere, unmixed or mixed with steam and other gases, will
further constitute a lifting power by reaction.
In carrying into practice the improved system of aërostation of my invention, I
prefer to employ machinery constructed according to one of the modifications
hereinafter described with reference to the accompanying drawings, the mechanical
means therein represented serving merely as specimens to indicate how the scheme
may be practically attained.
In the drawings,
Figure 1 is a vertical section, and
Figure 1A, a plan of the essential part of the air-ship.
But this
a, is the surface of resistance, the steam boiler. The steam is blown off
through pipes c carrying nozzles c¹ which may open into ėjectors or directly into
the atmosphere, and while being blown off, the steam carries along with it the
outside atmosphere L as well as the air of combustion K K' K². The mixture of
atmospheric air, steam and products of combustion is forced below the surface of
resistance a, and, naturally, has the tendency to retain its direction.
tendency is counteracted by the shape of the resisting surface and, accordingly,
operative power is furnished to the said surface a. The number of nozzles c
employed is so calculated that the spheroids of dispersion close up to each other.
The opening between the surface a and the cone is provided with a number of
flaps d which together act as a retaining-valve as soon as the machine begins to
sink. The machine, then, will act as a parachute.
Machines of the construction shown in Figures 1 and 1^, however, do not yet fulfil
all demands that may be desired of an aërostat for the reason that the momentum
of torsion generated by the volume of air traversing the nozzles is not balanced by
any counterforce. To obtain such balance I have provided means which are
illustrated in Figures 2, 3, 4 and 5.
In Figures 2 and 24, I have provided several conducting surfaces instead of a
single one, and the plurality of conductors are alternately receiving a positive and
a negative momentum of torsion. The said conducting surfaces may be provided
with conducting blades f, as in a turbine, by which interrupting blades the issuing
jet will be caused to operate to its utmost power of reaction.
In Figures 3 and 34, I have shown a construction in which the surface of
resistance of the kind shown in Figure 1 is a double one, one of the two surfaces
being provided with nozzles directed to the right, and the other surface with
nozzles directed to the left. The car, the boiler, etcetera, are carried between the
two surfaces in a central position.
In Figures
and 4, the curved surfaces are one-sided (cylindrical). The
operation of reaction, in this case, will not act in continuous lines, but at both
sides of the car, in straight lines directed parallel to the direction in which the
ship moves.
At the right side of Figure 4, I have shown a supporting and protecting
Burface n in addition to the surface of resistance a. The purpose of this supporting
and protecting surface n is to allow of mechanically elevating the ship during its
sailing flight. In this case the whole surface of resistance may resolve itself into
one-sided nozzles.
This
In Figures 5 and 5ª, I have shown a machine having but one symmetrical axis.
The nozzles are provided at the fixed ends of the wings whereby the atmosphere
is guided from outside and above against the car downwards and to the rear.
machine however, will not be able to rise vertically in a calm atmosphere, but it
will only be able to rise in flying forward or against the wind.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is―
1. A new method of aërostation, consisting in withdrawing the atmosphere from
above a surface of resistance and forcing it below the said surface in rapid motion
in such a manner that on its way down it receives components of pressure tending
upwards, and that, besides, it works by reaction, substantially as and for the purpose
described.
2. A new method of aerostation consisting in withdrawing the atmosphere from
above a surface of resistance, mixing it with the air of combustion employed for
heating the boiler and forcing the mixture down below the said surface substantially
as and for the purpose described.
3. A new method of aërostation, consisting in withdrawing the atmosphere from
above a surface of resistance, mixing it with the air of combustion employed for
heating the boiler and with the exhaust steam and forcing the mixture down below
the said surface, substantially as and for the purpose described.
4. A flying machine having means for withdrawing the atmosphere from above
a surface of resistance and forcing it down below the said surface, substantially as
and for the purpose described.
5. A flying machine having means for withdrawing the atmosphere from above
a surface of resistance and forcing the same down below the said surface in com-
bination with retaining valves provided in the passage of the air through the said
surface substantially as and for the purpose described.
6. A flying machine having means for withdrawing the atmosphere from above
a surface of resistance and forcing the same down below the said surface, in com-
bination with a supporting and protecting surface substantially as and for the
purpose described.
Dated this 20th day of April 1894
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.