Initially, under the Flight Test Program, Mir was scheduled
to operate up to 5 years. The station operated nearly 3
times as long (its service life reached more than 15 years).
Under the Flight Test Program, the Modules were scheduled
to fly as part of Mir for a period of 3 years (1095 days).
Below are given the actual operating periods of the Modules
as part of the Orbital Complex (as of December 31, 2000).
|| Operational use
as part of the OC, (days)
(749 - till depressurization)
Most of the onboard systems have significantly exceeded
service life characteristics specified in the log books
for assemblies, instruments, units and systems as a whole.
There were instruments, which operated more than 10 times
longer than originally specified service life.
In order to ensure a prolonged operational use of the Mir
OC, a special procedure was adopted envisaging extension
of its operating period on an annual basis with generation
of the required special reports on the systems, as well
as final conclusion of General Designer. In so doing, it
was allowed to operate the systems with exhausted service
life and use them until failure occurs ensuring the required
reliability and safety level.