Mission profile data is essential to sound design limit testing of systems and subsystems.
Contractors should be required to develop test environments using measured environmental data, where possible.
Design limit testing should be planned at multiple levels from parts to critical assemblies to subsystems to the system level.
The best design limit tests result when the complex combination of environments which represent the true field environment are simulated.
Test environments that are not representative of true worst case operating environments result in high risk of poor performance during operational use.
Because many design limit tests are viewed as "hurdles which must be jumped," the test program often becomes a success-oriented exercise.
High confidence, not test completion, is the goal of successful testing and the program should be structured to create this atmosphere.
All failure incidents are important and should be analyzed in detail regardless of when they occurred.
Subsystems which are being designed for multiple-use applications require tests be designed to simulate worst case conditions for all applications.
If a subsystem has been previously qualified, additional testing is required for any environment more severe than the original environment for which the subsystem was qualified.
Qualification of equipment by similarity can only be legitimized when quantification of the original and the current operational environments demonstrates their similarity.