1.1 Specifies tests to evaluate the effects of temperature variations on components or equipment used in aircraft. The tests have limited application and should only be specified in the relevant equipment specification when the thermal effects due to a change of temperature are significant to the operation of the equipment. The tests will enable equipment manufacturers to demonstrate that their equipment — when exposed to changes in the local atmosphere — will continue to function, and/or survive.
1.1.1 Two categories of test are described:
a) Temperature variations — Generally applicable to equipment likely to suffer gradual changes in atmospheric temperature, and
b) Thermal shock — Generally applicable to equipment likely to suffer rapid or instantaneous changes in atmospheric temperature.
1.2 The tests are not suitable for equipment installed in locations where the heat transfer rate is greatly increased by high velocity or turbulent air movement (for example, external to the aircraft or in intake or supercharger ducting ), where the temperature change affects only certain parts or surfaces of the equipment (for example, radomes, windscreens, etc ), nor is it applicable to equipment which is subjected to thermal shock by contact with a hot fluid (for example, hydraulic components ). For such equipment the relevant equipment specification shall detail the appropriate test to be conducted.
IS 8252 Pt.8-1979 history
1979IS 8252 Pt.8-1979 Aircraft equipment environmental testing Part 8 Temperature changes