min at 2000 psig. The hydraulic power unit will be referred to by the term, "power unit".

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MIL-PRF-62495B(AT)

3.4.5 Endurance. The hydraulic power unit shall operate the ramp or simulated ramp,

satisfactorily for 1500 cycles from the fully extended to full retracted positions of the ramp. Total

external leakage during the endurance test shall be no greater than 15% of the reservoir fluid

volume prior to the test. Fluid shall be added and recorded as necessary during endurance.

Following this test the number of cycles completed in 5 minutes shall not be less than 80% of

those at the beginning of the test (see 4.6.7).

3.4.6 Environmental conditions.

3.4.6.1 High temperature. After storage of 160 degrees Fahrenheit (�F) for a period of

48 hours, the power unit shall be capable of delivering no less than 0.4 gal/min at 2000 psig at an

operating temperature of 160�F. After operation at 160�F the power unit shall not exhibit

structural damage of deformation and shall meet the requirements of 3.4.1 through 3.4.5. The

power unit shall also meet the performance requirements of 3.4.1 when operated intermittently

(see 6.3) at 125�F for a period of 30 minutes (see 4.6.8.1).

3.4.6.2 Low temperature. After storage at -70�F, the power unit shall operate at 65�F

and shall meet the performance requirements of 3.4.1 through 3.4.3 (see 4.6.8.2).

3.4.6.3 Humidity. After exposure to 10 cycles of 95% relative humidity at a temperature

of 86�F, the power unit shall meet the performance requirements of 3.4.1 through 3.4.3 at the

conclusion of the fifth and tenth cycle (see 4.6.8.3).

3.4.6.4 Steam and waterjet cleaning. The power unit shall meet the performance

requirements of 3.4.1 through 3.4.3 after being subjected to the steam and waterjet cleaning

specified in 4.6.8.4.

3.4.6.5 Shock. The power unit shall meet the requirements of 3.4.1 after application of

the following shock loading (see 4.6.8.5):

a. Power unit mounting - As shown on Drawing 12293172.

b. Area of shock application - At opposite face of shock mount from power unit.

3.4.6.6 Vibration. The power unit shall meet the requirements of 3.4.1 after the

following vibration (see 4.6.8.6):

a. Power unit mounting - As shown on Drawing 12293172.

b. Area of vibration application - At opposite face of shock mount from power unit.

c. Level as shown in figure 2.