Various German documents which have become available for examination
reveal much information concerning the tactics, and apparatus employed by the
German Air Force in the use of smoke. It will be noted that German and American
smoke tactics are similar in many respects.
The following information obtained from German documents, was compiled
in the Office of the Chief of Chemical Warfare,
* * *
a. Weapons and Objectives
Aerial smoke apparatus can be used to establish smoke screens (a curtain
of smoke extending down to the ground) and area screens (a smoke cloud extending
close to the ground and covering a given area). At present, smoke does not appear
to be a suitable weapon for aerial combat.
Ordinary screens are established by a single aircraft or by several aircraft
following each other. Area screens, on the other hand, are produced by a number
of aircraft flying in close proximity. Two means of dissemination from aircraft
(1) Spray Apparatus -- Under air pressure, smoke acid, which is either
sulfurtrioxide or chlorsulfonic acid or a mixture of the two, is sprayed from tanks
attached to the plane. By experiments it has been found that planes spraying smoke
should fly at altitudes of 130 to 165 feet or less. Another German source states
that the minimum altitude for smoke cloud emission is 100 feet.
(2) Smoke Bombs -- Smoke bombs are used for establishing screens from
high altitudes. Usually the filling is either smoke acid or a Berger mixture
consisting of powdered aluminum and hexachlorethane. Release by aircraft is the
same as for HE bombs.
b. Atmospheric Conditions
Proper evaluation of weather conditions determines the effectiveness of
smoke screens produced by planes. The following data have been ascertained by
(1) Very Favorable Weather -- No wind or light wind, high humidity,
atmospheric conditions of early morning and dusk, also night time.
(2) Favorable Weather -- Wind velocity from 4 to 16 mph for spray
dissemination, 7 to 13 mph for smoke bomb, temperature not below 23° F, overcast sky.
(3) Unfavorable Weather -- Wind and sunlight cause convection currents
("noon weather"). Very strong wind and squally weather cause drifting and
scattering of smoke. Following a dry cool night, sunlight, and medium strong
wind will cause rapid dispersion of cloud ("Forenoon weather"). Heavy frost and
low atmospheric humidity result in poor smoke cloud formation. Smoke dissemination
may be made effective under unsatisfactory weather conditions by an
adequate increase in expenditure of smoke agents.
Surprise is an important factor in the use of smoke. Consequently in
defense, enemy smoke on one's own positions is an imperative signal for the
dispatch of one's own aerial reconnaissance. Situations which permit the use of smoke
by aircraft are:
(1) Attack on Ground Targets -- In HE bombing or in strafing attacks, smoke-disseminating
planes can be used to blind or neutralize the aimed fire of enemy
antiaircraft batteries and thus reduce the danger to the attacking planes. However,
premature employment of smoke in such cases may enable enemy planes to
intercept and thus jeopardize the effectiveness of the smoke on the antiaircraft positions.
The further danger exists that smoke may conceal the actual objective of the
friendly planes which are attacking.
During night bombing, the use of smoke may decrease the effectiveness of
enemy searchlights as well as their antiaircraft fire. Diversion screens may
deceive the enemy as to the true objective of the attack.
(2) Antiaircraft Defense -- For screening of important installations, including
airfields, aircraft factories, arsenals, business and industrial centers.
This use requires an adequate service to warn of approaching enemy planes and
a system to enable rapid response.
Area screens laid by aircraft can hamper the orientation of enemy aircraft
with respect to their objective by covering an area considerably larger than the
specific target. Dense masking screens may be established by mass employment
of smoke. (However, in practice, the Germans seem to depend on ground means of
dissemination for area smoke screens.) Even light smoke screens may suffice to
render orientation difficult, but they possess the disadvantage of being rapidly
dissipated. Thorough preparations are required to co-ordinate use of area smoke
with antiaircraft defenses.
(3) In Support of Ground Forces -- Thorough preparation and perfect
coordination with the ground forces, including a reliable communications system,
are necessary. Consideration must be given to the necessity of not interfering
with one's own aerial combat reconnaissance. These are some of the tasks that
may be undertaken:
Observation posts of enemy artillery and machine gun emplacements may
be blinded by smoke bombs. Flanking fire from sectors outside the main line of
attack may be neutralized by smoke sprayed from low-flying aircraft. This can
be particularly valuable in facilitating movement of units within the area under
enemy observation either in attack or defense.
Similarly, to break off combat, and during withdrawal, smoke may be
placed on the enemy to delay his movements and enable one's own ground troops
to withdraw with a minimum danger from effective enemy fire. Consideration
must be given to the possibility that smoke may limit or neutralize one's own
aerial defenses and may interfere with operations in adjacent sectors as a result
d. German Aircraft Smoke Bombs
The following table identifies and describes two of the smoke bombs used
by the German air force. It is probable that other bombs are available and that
they may be encountered. For a detailed description of the NC 50 bomb, see
Tactical and Technical Trends, No. 29, p. 27.
|Type of bomb
||On land and at sea|
||2'2-1/2" x 8" diam||
||Nose-white; body-aluminum color with 4 white bands, 1 in wide||
|Ballistics and suspension||
||Same as for SC50*||
||Same as for SC250|
||Mechanical tail fuze||
||Electric contact fuze (Zd. 26)|
|Duration of smoke cloud||
||30 to 40 mins||
||2 to 3 mins|
Doctrines set forth by the Germans in the documents under review are for
the most part standard practice. It is questionable, however, whether the use of
smoke-spraying aircraft to produce large area screens is anywhere nearly as
effective as ground installations for this purpose. Actual German practice seems
to confirm this.
Direct spraying of smoke on enemy ground units by low-flying aircraft to
prevent flank fire during an attack would seem to be questionable tactics. The
smoke-laying aircraft would be extremely vulnerable in such an operation. However,
it may be intended to lay smoke in an adjoining area which will drift over the units
which it is desired to blanket.
During the Grecian campaign smoke was at times used by the Germans to
indicate targets. Reconnaissance planes would lay down a streamer of smoke to
indicate the direction of the targets. In one case a German aircraft circled a
camouflaged airfield and laid down a smoke trail. In another, a winding road was
outlined for several kilometers by smoke placed over it by two reconnaissance
bombers. Following shortly, 20 bombers flew over the smoke trail, 10 on each
side, and dropped their bombs.
*See Tactical and Technical Trends, No. 37, p. 27.