Design and Stress Analysis of Extraterrestrial ... - The Black Vault

Table 1.2.
Ilmpulse J LPRE PEE MEE
/s e.2-3.5)'103 (50-100).103 up to 600.i03
Extrateri'zestrial electrical rocket motors have a specific
imPulSe higher \than LPRE. This explains the preferred use of
electrical rocket motors for interstellar flights. The value of
specific impulse, In each concrete case should be optimal.
Reliability and:' servi:`e life of ERE
Reliability is usually understood as the property of the product
to execute assigned' functions, preserving its operating indexes
within assigned limits during the required time interval -or required
operating time.
The reliability of a product is explained by its ".dependability,"
"maintainability," "storage stability," and also by the "longevity"
of its parts.
In this section we examine only problims relating to longevitY'.
A broader discussion of the problem of relfdbIlitly is given in
section 1.4.
Longevity is- the property of a part to preserve efficiency
up to a limiting condition with the necessary interruptions for
maintenance and repair.
The indexes of longevity are life and service.period.
Life is characterized by the length of operating time up to
a limiting condition Specified in the technical specifications and
records. The service period is the length of time by the calendar
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