AIA NAS1717

INACTIVE FOR NEW DESIGN * X-REF NAS380

Purpose

This standard specifies reliability demonstration guidelines and
practices for liquid rocket engines.

Application

This standard provides methodology for conducting reliability
demonstration programs suitable for use with liquid rocket engines.
To be most meaningful and statistically correct, a demonstration
program should be conducted at the highest practical level of
assembly and under conditions representative of those experienced
in the use environment.

Program limitations in conjunction with need for data at early
dates in the program force certain compromises which historically
have proven acceptable. The first of these compromises is that it
is necessary to utilize static test results. Second, design and
development configuration engines which closely approximate the
planed flight engines may be included in the demonstration sample.
Finally, certain programs may not provide for sufficient complete
engine tests and subsystem test results may be combined with tests
of the complete engine to produce a sufficient sample for
reliability demonstration.

Validity of the reliability demonstration program is adversely
affected as the samples depart from the use configuration and
environment. The extent to which sub stem data is combined with
data obtained from tests of the complete engine system shall be
mutually agreed to between the contractor and procuring
activity.

General requirements and the reliability demonstration criteria
described in the detailed requirements (Section 5) will be the
principal basis for assessment of liquid rocket engine reliability.
Specific demonstration plans will be prepared by the contractor in
keeping with customer requirements, as part of the overall
reliability program plan.