THE GERMAN AIRSHIP FLEET
Many reports have been current concerning the exact dimensions of the
airship fleet that Germany can put into action. It has been said that
she has been extremely active since the beginning of the present war
in adding fresh units to the forces she had available when the war
broke out. It has also been rumoured that she is making a new type of
Zeppelin--one much smaller, and which will have greater speed than the
larger type.
GERMAN AIRSHIPS IN THE SPRING OF 1913.
-------------------+--------+-----------------------------------
| | Motive power.
| Volume +-----+----------+----------+-------
Type. | m. | | | h.p. per | Max.
| | No. | Type. | Motor. | Speed.
| | | | | m/s
-------------------+--------+-----+----------+----------+-------
Zeppelin | 17,700 | 3 | Maybach | 150 | 21
Zeppelin | 18,700 | 3 | -- | 150 | 21.1
Zeppelin | 18,700 | 3 | -- | 150 | 22
Zeppelin | 18,700 | 3 | -- | 150 | 22
Zeppelin | 22,000 | 3 | -- | 150 | --
Zeppelin | 20,000 | 3 | -- | 170 | --
Zeppelin | 18,700 | 3 | -- | 170 | --
Zeppelin | -- | -- | -- | -- | --
Parsifal | 4,000 | 1 | Daimler | 85 | 14
Parsifal | 7,500 | 2 | N.A.G. | 110 | 15
Parsifal | 8,000 | 2 | Maybach | 180 | 18.8
Parsifal | 10,000 | 2 | Koerting | 200 | 18.5
Parsifal | 8,000 | 2 | N.A.G. | 110 | 16
Parsifal | 10,000 | 4 | Maybach | 180 | --
Siemens-Schückert | 15,000 | 4 | Daimler | 125 | 19.8
Schutte-Lanz | 19,500 | 2 | Daimler | 270 | 20
(1) Gross-Basenach | 5,200 | 2 | Koerting | 75 | 12.5
(2) -- | 5,200 | -- | -- | 75 | 12.5
-------------------+--------+-----+----------+----------+-------
(1) and (2) as in 1911; since then they have been renovated,
and no doubt their speed and volume are much greater.
We must accept with some reserve the reports that are current in this
respect, and it may be pointed out that in accounts of the doings of
Zeppelin airships in the papers it can be reasonably doubted whether
all the Zeppelins mentioned are in reality Zeppelins. Probably some are
the smaller types, such as the Gross or Parsifal. The word Zeppelin
seems to have become synonymous with a German airship, and the wounded
soldiers or prisoners who are responsible for many of the stories told
would not be likely to have complete knowledge of the distinctions
between classes of airships.
Though what Germany is exactly doing in way of new manufacture
must remain in much fog, still we can form some opinion as to her
preparedness with aircraft on the lighter-than-air principle from our
knowledge of what she possessed last year.
The table on the opposite page will show that her fleet of airships,
including those under construction, was then by no means negligible.
A nation possessing such a fleet of large airships as Germany does must
be provided with sheds (hangars) for their reception in all parts of
the country, and by the table that is appended it will be seen that in
this way last year Germany was very amply provided.
I am indebted to the _Aérophile_ for the following list of German
hangars for dirigibles, with dates of construction and names of
owners:--
-------------------------+--------------------------+------------------
Place and Date of | Proprietors. | Observations.
Construction. | |
-------------------------+--------------------------+------------------
Aix-la-Chapelle | -- | Designed for 1914
Allenstein | -- | Designed for 1914
Baden--Baden-Dos (1910) | -- | --
Berlin--Biesdorf (1909) | Siemens and |
| Schückert | --
Berlin--Reinickendorf | -- | --
Berlin--Johannisthal | Aëronautical |
(1910) | Sport Society | --
Berlin--Johannisthal | |
(1911) | -- | --
Berlin--Tegel (1905) | Prussian Army | --
Berlin--Tegel (1907) | Prussian Army | --
Berlin--Tegel (1908–10) | Prussian Army | --
Bitterfeld (1908) | Luffahrtzeug | --
| Society |
Bitterfeld (1909) | Luffahrtzeug | --
| Society |
Braunschweig | Airship Harbour | Designed for 1914
| Society of Brunswick |
Cologne | -- | --
Cologne--Leichlingen | Rheinwerke | --
| Motorluftschiff |
| Society |
Cologne--Nippes | Clouth | --
Cuxhaven | German Navy | Designed for 1914
Dresden | City of Dresden | Will only hold
| | one balloon
Düsseldorf (1910) | City of Düsseldorf | --
Cologne--Bickendorf | |
(1909) | Prussian Army | --
Frankfurt am Main | |
(1911) | Delay | --
Friedrichshafen (1908) | Zeppelin Society | --
Friedrichshafen--Manzell | Workshops of the | --
(1900) | Zeppelin Society |
Gotha (1910) | Town of Gotha | --
Graudenz | -- | Designed for 1914
Hannover | -- | Designed for 1914
Hamburg--Fuhlsbüttel | Hamburg Airship |
(1911) | Harbour Society | --
Hamburg--Hansa | -- | --
Kiel (1910) | Union for Motor-Airship | --
| Travel |
Königsberg-in-Preussen | | --
(1911) | Prussian Army |
Leehr | -- | Designed for 1914
Leipzig | Leipziger Luftschiffland | --
| Flugplatz Gesellschaft |
Liegnitz (1913) | Prussian Army | In construction
Mannheim--Schwetzinger | -- | --
Mannheim--Rheinau | Luftschiffbau |
(1909) | Schütte u. Lanz | --
Metz (1909) | Prussian Army | --
Potsdam, near Berlin | Zeppelin Society |
(1911) | -- | --
Posen | -- | Constructing
Schneidemühl | -- | Building
Strasbourg | Prussian Army | --
Thorn (1912) | -- | --
Trèves | -- | Building
Waune (1912) | Rhenish-Westphalien | --
| Flying |
| and Sports Club |
-------------------------+--------------------------+------------------
Such monster airships as the Zeppelin call for a large proportion
of pure hydrogen. This is, indeed, manufactured on a large scale in
Germany. It is produced in quantities by the electro-chemical works
at Bitterfeld, Griesheim, and at Friedrichshafen, specially for the
needs of the Zeppelins at the latter place. There are also works for
the production of very pure hydrogen by electrolysis at Bitterfeld,
Griesheim, Gersthofen, and Dresden.
In the particular way Germany means to use her lighter-than-air fleet
in the present war time will show. If, however, there have not yet
been attempts at any combination of action, individual Zeppelins have
already played the rôle of dreadnoughts of the air. Though their powers
have been no doubt exaggerated, they have been the terror of some
Belgian cities.
Early in the morning of August 25th a Zeppelin airship visited Antwerp,
and drifting silently with the wind steered over the temporary Royal
palace. There it discharged six highly explosive bombs. Not one found
its intended mark, though all fell near the palace. One appears to
have been very near hitting the tower of the cathedral. Though the
bombs failed to attain the object sought, no less than six or seven
persons were victims to the outrage. One struck a private house,
killed a woman, and injured two girls, killed two civic guards, and
wounded another. One bomb fell in the courtyard of the hospital of St.
Elizabeth, tore a hole in the ground, smashed the windows, and riddled
the walls.
The Zeppelin repeated its visit early in the morning of September 2nd,
but this time with less deadly result. The bombs only wounded the
victims. The experiences of the first visit had given effective warning
against a repetition of aërial invasion. The city had been darkened,
and the airship was attacked from the forts and the high points of the
city as soon as it made its appearance. The crew of the airship seem to
have been struck with panic when it failed to find its bearings over
the darkened city.
It appears they suddenly dropped all their bombs as ballast and rose
quickly out of harm’s way. The bombs used on this occasion were not
of the same type as those used on the previous attempt on the city.
The latter were of high explosive power designed to destroy buildings.
The former were covered by thin envelopes, and held together by
mushroom-shaped rivets. They were filled with iron bolts and nuts, and
were evidently designed for the destruction of human life. It is stated
that this is a type of bomb which has never been used by artillery,
being made on the same model as that used by the notorious French
robber, Bonnet.
In reference to airship raids over cities, it has been suggested in
America that the air in their immediate neighbourhood should be mined.
This could be done by having a number of captive balloons or kites,
the mines on which could be discharged electrically from the ground.
For future wars there will no doubt be devised some form of travelling
aërial torpedoes for destroying the intruding airships. Such torpedoes
would, however, have to be capable of guidance. As has been pointed
out by Mr. W. F. Reid, in 1884, at the siege of Venice, the Austrians
used free balloons for the purpose of dropping bombs upon the town.
The bombs were attached to the balloons in such a way that after the
burning of a certain length of safety fuse, the connection was severed,
and the bomb fell. The length of fuse was calculated according to the
speed of the wind; but, unfortunately, when the balloons rose, they
entered an upper air-current travelling in a different direction from
that below, and many of the bombs burst in the Austrian lines, whence
they had started. Thus it would not be expedient to let loose ordinary
unmanned balloons loaded with timed explosives, even if the direction
of the wind seemed favourable, for their meeting an approaching airship
fleet, as an upper current might bring them back over the city, where
they might do mischief.
It is, however, quite conceivable that in the future aërial torpedoes
may be devised in the shape of unmanned balloons or aëroplanes
controlled by wireless waves of electricity. Those who saw the
striking experiment of steering a small navigable balloon in a large
hall entirely by wireless electric waves must have realised the
possibilities which may thus be opened out in the future.
* * * * *
While writing, the news has come that another Zeppelin has dropped
three bombs on Ostend, the casualty list being one dog. Two unexploded
projectiles were found on a field near Waeragheim. These were probably
thrown from the same airship. They show how constantly missile throwing
from a moving airship may fail to come near the mark. There is no doubt
that to hit particular objects aimed at from airships is by no means
an easy matter. Success would seem to require considerable training in
this particular method of warfare. The late Colonel Moedebeck, in his
well-known pocket-book of aëronautics, makes the following remarks on
the throwing of balloon missiles:--
We may assume that, if handled skilfully, the object aimed at will
be hit very exactly. We must distinguish between the throw when the
airship is at rest and that when it is in motion. In throwing out
while at rest, which is only possible when the airship can travel
against the wind, the following points must be considered:--
(_a_) _The height of the object._--This may be accurately
determined from the contour lines on the map, or from a
determination of its normal barometric height. Both must be done
before starting.
(_b_) _The height of the airship above the object._--The barometric
height is read and reduced to normal conditions. The difference in
heights as found from (b) and (a) gives the height above the object.
(_c_) _The velocity of the wind._--May be read on an anemometer in
the airship, or determined beforehand by captive balloons.
(_d_) _The time of fall._--Given by the law of gravitation from the
determination under (b).
The height of fall = h = gt²/2.
Whence the time of fall t = √(2h/g).
(_e_) _The resistance of the air._ R = (γ/g)Fv².
(_f_) _The leeway._--The longer the fall, and the lighter and
larger the falling body, the stronger is the drift. For known
missiles, the drift for different heights and wind velocities may
be determined practically.
(_g_) _Unsteadiness of the airship._--The irregularity of the
pressure of the wind, and its constant variation in direction,
renders it impossible for the airship to remain perfectly steady.
The elements stated under (_b_) and (_f_) must be rapidly
determined, and suitable tables have been prepared for this
purpose. The irregularity of the wind and the peculiarities of the
airship mentioned under (_g_) render a preliminary trial necessary.
The drift also is determined by this method, before the large
air-torpedo is cast out.
The air-torpedo must be brought by sight vertically over the object
by steering the airship, the value of the mean drift previously
determined being allowed for.
In throwing out a missile while actually travelling, the velocity
of the airship must be taken into account, as well as the elements
(_a_) to (_g_) given above, since this velocity is also possessed
by the body thrown out.
The determination of the proper point is now greatly increased in
difficulty. Its position is a function of the relative height of
the airship above the object, of the velocity, and of the drift,
and allowance must be made for all these factors. For this purpose,
motion, either with or against the wind, is the simplest. On
account of the point on the earth over which the missile must be
thrown out not being in general well marked, it is necessary to
use also angles of sight.
The problem before the aëronaut is, then, as follows:--For a
given height, velocity, and drift to find the necessary angle of
depression at which the missile must be thrown out in order that it
may fall on to the object.
The casting out of the missile against the object while travelling
is governed, therefore, by the same rules as those governing the
discharge of a torpedo from a torpedo-boat.