Downloaded from https://www.everyspec.com AMCP 706- I identifying-information, environmental con- After the design is established, reliability ditions, operating hours or cycles, and failures, tests can be used to make decisions about system reliability and to determine if relil- 1-2 RELIABILITY TEST PROGRAM ability goals have been met, The procedures described in this volume can be applied to a Testing is an important and expensive part variety of situations.
The tests range from of the development program for an equip- quality-assurance tests, which are performed ment or system, Because reliability testing is at the plirt level on lots of components, to expensive, the test program must be designed reliability demonstration tests used to prove carefully to fit into the overall development that a system indeed meets its reliability program, requirements. The information provided by a reliability Demonstration tests on systems can be per- test program can be used at any point in the formed in three distinct phases: system life cycle.
A well planned program of functional environmental testing must be con- 1, Specifc subsystems and equipments ducted during system design and development must be testad to determine If they meet the in order to achieve the required reliability reliability requirements allocated to them. and to provide data for improving reliability, The equipments must be evaluated in a con- These tests are used to measure the reliability trolled environment in which performance is of components, equipments, and subsystems monitored by means of an instrumented test used in a system. Tests also are used to de- set-up.
Equipments that do not meet tell- sign tools to evaluate the relationship between ability requirements must be redesigned. various environments and stresses, and reliabil- ity. The reliability tests performed during 2. After individual equipments have been development answer the basic question of tested, they must be mated and the entire whether or not the design really works, system must be subjected to realistic opera- tional procedures and environments. Reli- A reliability measurement program must ability data are gathered by means of a care, be planned carefully, The contractor develop- fully organized data reporting system.
plan that includes all reliability tests to be by Army personnel who exercise the system performed during the program. The tests in the operational environment, Reliability must be designed to make maximum use of data are gathered along with many other data A all data produced on the program. The reli- items. These tests permit the reliability per- abiIty test program must be integrated with formance of Army systems to be determined other system/equipment test programs in in realistic operating environments, and they order to minimize wasted effort. A number may uncover weaknesses masked in the pre- of standard test plans have been developed vious tests.
to guide contractors and Army project man- agers (Refs. 6, 7, and 8), The test plans in Achiuved reliability must be demonstrated MIL-STD-781 can be used for testing equip- formally at specified times during the pro- ments and systems whose failure characteristics grant. Demonstration testing must be per- are governed by the exponential distribution, formed at the system level, and at the sub- The sampling plans described in MIL-STD-105 system and equipment levels. Demonstration can be used for I-shot devices.
Modifications test plans must include a definition of failure of tho procedures in MIL-STD-105 for com- criteria, applied environments and stresses, ponents governed by a Weibull distribution are test procedures, and the applicable statistical described in TR-7 (Ref. 4). test plans. ( .................. "