1.1 Purpose
The purpose of this test is to help determine the synergistic effects of combinations of temperature, altitude, humidity, input electrical power, and vibration on airborne electronic and electro-mechanical materiel with regard to safety, integrity, and performance during ground and flight operations. The synergistic effects may induce failures that would not be exhibited during individual environment testing. New to this method is the addition of input electrical power as an environment; to include voltage/frequency variations, and transients (if applicable) which are inherent to the system. While it is virtually impossible to replicate the complex mix of environments which can be seen during transport, storage, operation, and maintenance, the intent is to apply representative combinations of stresses to the materiel to determine performance and capabilities.
1.2 Application
NOTE: This Method is not intended to be used in lieu of Method 507 due to the cyclic and cumulative exposure required for Humidity testing. Additionally, this Method is not intended to be used in lieu of 500, 501, 502, and/or 514 unless properly tailored and authorized in the requirements documents.
- a. This Method was developed and based on rotor or fixed wing aircraft/platforms. The test procedures are applicable to all aircraft equipment. However, with tailoring, this method may also be applicable to other commodities; i.e., ground vehicles, support equipment, man-mounted equipment, etc.
- b. Use this Method to evaluate materiel to be deployed in/on aircraft or ground support equipment where temperature, altitude, humidity, input electrical power, and vibration, or any combination of these, may induce failures.
- c. This Method is primarily intended for actively powered materiel operated at altitude, i.e., aircraft and missile electrical/electronic equipment, mission equipment, electro-mechanical equipment, etc. This Method may be used for engineering development, for support of developmental and/or functional testing, and for other similar purposes.
- d. Use this Method to provide an option for use of vibration in combination with the climatic elements, or for use of the climatic tests in combination with each other. This is often noted throughout the text. Generally, the combined environment test simulates those synergistic environmental effects that occur for the majority of the deployment life.
1.3 Limitations
- a. Limit use of this Method to evaluating the combined effects of three or more of the following environments: temperature, altitude, humidity, input electrical power, and vibration.
- b. This Method does not normally apply to unpowered materiel transported as cargo in an aircraft.
MIL-STD-810H
METHOD 520.5
- c. The tailored test cycle should not include short duration vibration events or those that occur infrequently in the test cycle. These events include firing of on-board guns, extreme aircraft motion, and shock due to hard landings. Test for these events separately using the appropriate test method.
- d. This Method is not intended to be used for temperature/vibration testing, unrelated to the synergistic environmental test combinations detailed in paragraph 2.2.3. Refer to Method 514.
- e. This Method is not intended to be used to test materiel to be installed or operated in space vehicles, aircraft or missiles that fly at altitudes above 21,300 m (70,000 ft).