- Procedure II is intended for testing of unique mission profiles and troubleshooting. The profile steps must be tailored for the specific application. Steps may be added, repeated, or deleted based on the specific mission requirements.
- Temperatures and Altitudes for troubleshooting shall be obtained from actual mission data, if possible.
- Temperatures and Altitudes for mission specific testing shall be obtained from the relevant program office or mission needs statement based on the mission geophysical location.
- Temperature Ramp Rate: IAW equipment or platform specification. If not specified, then <5 Deg C/min.
- Altitude Ramp Rate: IAW Equipment for platform specification.
- Humidity: The specific relationship between temperature, altitude, and humidity is highly variable and the profile should be considered as an example only. This parameter should be analyzed based on the specific mission geographic and atmospheric conditions. (Note: in the attack segment, if test chamber is unable to apply humidity at altitude, then this segment may be set to site pressure to incorporate the humidity parameter. This simulates a low level attack in a humid environment.)
- Input Electrical Power:
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a. Voltage: Alternate from cycle to cycle; Nominal, High, Low, High, etc. See Tables 520.5-III, IV, V, and VI for guidance.
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b. Frequency Variation: The input electrical power frequency shall be varied from cycle to cycle. See Tables 520.5-III, V, and VI for guidance.
Note: Flight critical equipment may be required to operate under abnormal and/or emergency voltage condition. See Table IV and MIL- STD-704 for the appropriate levels. See paragraph 2 2.4.4. for additional guidance.
- Supplemental Cooling temperature and mass flow rate shall be IAW the platform/system specification. There shall be no ECS supplemental cooling for the first 2 minutes following power on. This shall be followed by a linear drop in the ECS supplemental cooling air temperature to the specified cooling temperature. The ECS cooling air temperature ramp rate shall be determined from the platform ECS specification. For RAM cooled compartment a thermal analysis shall be performed per the guidance in paragraph 2.2.4.1.1.a.
- Vibration may be performed separately with temperature. Vibration is intended to be tailored for the test items specific rotorcraft and/or fixed wing application and the levels should be in accordance with the levels expected during the specific mission segments.
- It is preferred that consecutive cycles be run continuously; however, if test chamber operations preclude continuous operation, then the transition from high altitude to site, and from loiter temperature to minimum temperature shall be completed prior to interrupting the cycles. These conditions shall be maintained until the cycle is resumed.
- Pre-Test, Post-test and Functional tests are performed to verify consistent satisfactory performance throughout the test. Pre and Post tests are generally the same. Functional tests, especially during altitude exposure, may be dependent on chamber access. These tests should be tailored per guidance in Part One.