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DISCUSSION OF VARIOUS SITUATIONS
Various situations which might occur are described below, along with
the estimated probability of detonation in each case. In each situation
malfunction of certain parts of the system is assumed and the probabilities
estimated for failures of the remaining devices which could result ina
hazardous detonation.
A detailed explanation showing the basis of the esti-
mates for each situation is given in the appendix.
Numerical estimates are made for probabilities of specific types of
component failure and these quantities are combined to arrive at a combined
figure for the probability that detonation will occur in a certain situation. there is no statistical data to support these estimates; they are
based only on judgment as to what should be expected of the component reliability. It is believed that the resulting probabilities of premature
are small enough so that a wide margin of error in the individual estimates
would not affect any conclusions which may be dravm from this report.
i. Handling operations up until the time of installation of the high
voltage jumper cable "key",
Prior to the installation of the "key" there is no way in which a firing
voltage can reach the capacitor bank, so the probability of a premature
detonation is essentially zero,
This includes the effects of fire, since
a fire could contribute no probability of establishing a high voltage path
from the battery to the capacitor bank when the "key" is not installed.
2.
After installation of the key and prior to launch.
At this time a nuclear detonation can occur if signals are supplied
to the warhead. These signals will be supplied in the proper sequence by
the arming and fuzing timer if it receives unlock and start signals, provided the signals can get through the T=+107 safing and.arming device. Certain signais from the missile system are required in order that solenoidoperated detents in the T-107 are released; these same signals would actuate
the arming and fuzing timers and battery. The probability of premature,
therefore, is the probability that the missile systen will supply these
signals and that certain mechanical actions will occur in the T-107. It is
estimated that the probability of detonation in this period is about 10-2,
excluding fire. In the event of fire the probability is estimated to be
about 10-9,
3. Launching occurs and missile moves from the pad, but not far enough
so that the electrical’ system is destroyed on impact after thrust is term-
inated,
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