The movement of troops by rail is always attended by dangers incident to sudden air
attacks. The extent to which these can be successfully warded off, may often
determine the final outcome of a battle.
The German Air Force Manual includes a section entitled "Protection of Troop Trains
Against Air Attack."
Where trains are to be protected by means of antiaircraft machine guns, the troops transported
will furnish 3 antiaircraft sections. Three antiaircraft railroad cars are provided, one at the
center of the train, and one at the center of the front and rear halves of the train. There are
two types of railroad cars: an open high-sided car with a superstructure or scaffolding, and an
open low-sided car. The type of car used depends upon the make-up of the train. Thus in the
case of non-motorized units which will use roofed cars for the most part, the guns must be
placed at a considerable height in order to get a clear field of fire. Therefore, two high-sided cars
with a superstructure are used, and only one low-sided car. This allotment of cars is reversed for
motorized units. The high-sided antiaircraft cars are spotted in the train with the roofed
cars, the low-sided antiaircraft cars with the open cars. Where possible, the guns are
mounted on vehicles when the low-sided car is used.
In conjunction with the antiaircraft machine guns, 20-mm. antiaircraft guns may be used. When
the 20-mm. guns are to be used, 2 antiaircraft sections are formed, and 3 low-sided cars, specially
designed for antiaircraft use, are provided. One car is placed at the tail-end of the train and
another at the center. The third car is placed immediately behind the locomotive so that when
the direction of the train is changed, as in switching for example, the tail car need
not be shifted; if possible, this car should also be provided with a gun. At least 2 open
cars with low loads should be coupled to either side of these special antiaircraft cars in
order to give a good field of fire. Additional 20-mm. guns may be used when required.
Care must be taken that the guns are not struck by obstructions, such as passing
trains, tunnels, signal posts, etc. For this purpose, lookouts are detailed to
observe on each side of the train. When not firing, the 20-mm. guns should be pointed
directly to the front or rear depending on their sector of fire.
No warning of attacks can be expected, so all antiaircraft personnel must be kept in a
constant state of readiness. There are two aircraft watchers, one observing an arc
of 180° to the front, the other to the rear. These watchers should be selected from
among the best-trained men and relieved frequently.
The procedure for firing is as follows: The normal zone of fire of the guns near the front of
the train is to the front, that of the guns near the rear, to the rear; these guns will support
each other only when there are no planes within their respective normal zones. The guns in the
middle of the train support the front or rear guns as the situation may require. When the
train is moving, only tracer ammunition will be used since the motion does not permit
accurate sighting. Care must be taken not to shoot up signal posts and other
installations, and even if under attack no firing may be done where there are overhead
powerlines. At prolonged halts, when for one reason or another fields of fire are
obstructed, the guns should be dismantled and set up at suitable points in the
surrounding countryside.