Description / Abstract:
1. SCOPE:
The terms used in most engineering technologies tend to be physical
characteristics such as speed,
rate of turn, and fuel consumption. While they may require very
careful definition and control of
the way in which they are measured, the terms themselves are not
subject to different
interpretations. Reliability, maintainability and supportability (RMS)
however, use terms that are
mathematically defined. As a result, there are more than 2000 terms
defined in just the documents
reviewed so far, many of which have multiple interpretations.
This proliferation of definitions of the terms leads to problems when
one attempts to compare the
performance of one system to another. For example, the RMS pertomrance
of a transport aircraft from
the commercial arena is measured using metrics that are not the same
as those for a fighter or
attack aircraft from a military service. It is accepted that some of
the metrics may be unique
because of the nature of the missions, but it is the strong conviction
of the Government and
Industry practitioners who make up the SAE Committee G-11 that there
should be some fundamental
definitions used for all hardware systems.
Accordingly, in early 1986 the SAE G-11R (Resources) subcommittee was
formed and tasked to review
relevant RMS documents, extract any applicable terms, and through a
system of logical selection
compile a series of terms and definitions that would be recommended
for the Aerospace Community.
There are undoubtedly many more documents that need to be reviewed for
the definitions they
contain, for example, we have specifically excluded "software
reliability" from this edition. Also,
there is a need to reconcile the terms and their definitions with
those commonly used in the
commercial aircraft business. It is planned that the SAE subcommittee
work shall continue to result
in future revisions that will broaden the scope of the document. This
is the document that has been
prepared by the SAE G-11R subcommittee. Future updates of this
document will continue to reflect
the converging of defense and commercial technology and standards.