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and fire hazards) liquid propellant component, especially in monopropellants. This
conclusion is backed up by the following relatively recent serious accidents.
An accident in the Russian submarine
Kursk
which sank in the Barents Sea in-
volved an h/c H
2
O
2
-fueled torpedo explosion. Before this accident, on 18 March
1980, an A-7 rocket exploded during fueling, killing 48 people at the Plesetsk space-
port [1]. As was discovered by the author of this topic, the accident was caused by
the thermal explosion of h/c H
2
O
2
which came into contact with catalytically active
Pb-containing solder. The soldering alloy was mistakenly used by a manufacturer
to solder a stainless steel screen filter in the h/c H
2
O
2
supply line. The author was
honored with a Plesetsk Spaceport Diploma for investigating the accident and devel-
oping a number of practically important recommendations regarding fire and explo-
sion safety when using h/c H
2
O
2
. Nowadays, since the widespread use of h/c H
2
O
2
has meant that it must be stored for a long time in tanks of various machines and
devices, the issue of its heterogeneous decomposition upon contact with surfaces
of construction materials is still very important. Data on this matter is scarce in the
literature.
In contrast to h/c H
2
O
2
, at long-term storage temperatures liquid hydrazine ex-
hibits high thermal stability. Because of this, as well as its high-energy character-
istics, hydrazine is widely used for various applications (for example, in the Space
Shuttles) and is considered a promising material for use in future space engineering.
However, in order to be able to analyze the performance of hydrazine in units that
are used for several years, data on its low-temperature homogeneous and heteroge-
neous decompositions upon contact with construction materials of tanks, pipelines,
etc., are required. In addition, it is also important to obtain information on the high-
temperature decomposition and thermal explosion of hydrazine. This necessity is
explained by considering the characteristics of a catalytic unit operating according
to a standard cyclogram. During a stop phase, monopropellant is not supplied to
the unit. Under these conditions, hydrazine in the cutoff valve and in the supply
pipeline rapidly heats up due to the heat from the cooling (but still burning hot) cat-
alytic unit. Without employing special measures in order to suppress the heating-up
effect, thermal explosions of hydrazine can occur.
Such a scenario was discussed in [2], where the increased explosion hazard pre-
sented by hydrazine use in the Space Shuttle was emphasized (hydrazine is used in
a turbo-compressor unit that drives the hydraulic system).
11.2 Some Additional Experimental Techniques
The kinetics of the thermal decomposition and explosion of h/c H
2
O
2
and hydrazine
was studied using a method described in Sect. 10.5, a manometric method devel-
oped by Prof. Nechiporenko (Institute of Chemical Physics Problems of the Rus-
sian Academy of Sciences), and techniques using specially designed kinetic devices
(automatic volumetric device (AVD) and Microdroplet).
The use of the AVD and Microdroplet devices allows one to obtain information
about the decomposition macrokinetics over a very wide temperature range: high
temperatures correspond to conditions in the pipelines of a liquid rocket engine
