Tactical and Technical Trends, No. 20, p. 26, gave an analysis of some
samples of gas and oil used in German mechanized vehicles. It is evident from
the following report that the enemy continues to maintain a high standard for
gasoline and other fuels.
a. Aviation Gasoline
There are still two chief types of fuel in use in the Luftwaffe: viz.,
B. 4 ("blue," generally used in bombers) and C. 3 ("green," used in fighters).
During the last year, there has been no fundamental change in the quality
or method of production of the blue-type fuel. The base spirit is of petroleum
origin. If it emanates from current Axis production, it probably comes from
Rumania. It is understood, however, that the quantities involved do not preclude
the possibility of its derivation from pre-war or captured stocks of American
or Venezuelan aviation gas.
It is blended to 90-octane by the addition of mixed high-octane gasolines,
aromatics or hydro-gasoline, and T.E.L. (tetra-ethyl-lead). A previous
conclusion that usually two of these blending agents (and T.E.L.) are used in
conjunction has been confirmed. It has been suggested that the added high-octane
gasolines come from captured stocks, and this is a possible explanation of the
small concentrations used.
The reason for the continued use of blue fuel is not yet clear. There is
no evidence of any increased use of hydro-gas--if anything, the reverse is true.
Evidence strengthens the view that the C. 3 green fuel is capable of
giving very high performance, and that it has an exceptionally good rich-mixture
performance, considerably better than 100-octane aviation gasoline.
The origin of the aromatics in the green fuel is not certain, but the possibility
of making them by the treatment of hydrogenation products from creosote
has been established.
The method of preparation which most closely fits the analysis of this
green fuel is the blending of a light cut of straight-run petroleum spirit with
gasoline or naphtha, produced from creosote by some form of aromatising
hydrogenation, and with the addition of high-octane materials.
All German aircraft fuels continue to show the presence of about 5.5
milliliters of T.E.L. per imperial gallon.
b. Motor Fuels
The test results on motor fuels from Europe, as well as other information
available, suggest that T.E.L. is not being used, but that alcohol is being
employed to a limited extent. A number of samples from the Middle East
contained T.E.L.; others contained alcohol. A fair proportion of both sets of
samples from Europe and the Middle East contain a high percentage of aromatic
hydrocarbons, indicating that there is no general shortage of aromatics in Germany.
Octane numbers vary widely, and from the very low antiknock value of
some of the motor gasolines captured in the Middle East, it would appear that
local blending with benzol, alcohol, and/or T.E.L. must take place.
c. Other Fuels
The high-speed diesel-fuel samples from Europe are all of low
pour-point, some as low as minus 40° C; it is suggested that a number contain
Fischer-Tropsch gas oil (probably a special process for mixing gas oil) mixed
with creosote. The low pour-point indicates that extensive provision has been
made for dewaxing. On the other hand, some high-speed diesel-fuel samples
from the Middle East are of much higher pour-point, showing that the enemy
may have segregated them according to the type of climate in which they are to
Several fuels appear to be of Rumanian origin, while one may be
Persian. For heavy bunker fuels, coal tar products are being used in some cases.