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|  MIL-T-48558B(AR)
3.7 Environmental.
3.7.1 Storage temperature. The telescope shall show no
evidence of physical failure when thermally stabilized at ambient
temperatures of +160F (+71C) 5F (3C) and -50F (-46C)
5F (+3C) for a period of 4 hours 15 minutes at each
temperature.
temperature. The telescope shall meet the
3.7.2 Operating
applicable requirements of 3.12 while exposed and thermally
stabilized 2 hours + 15 minutes at ambient temperatures of +150F
(+65) + 5F (+3C) and exposed and thermally stabilized for 4
hours + 75 minutes at an ambient temperature of -50F (-46C)
5F (+3C). Upon return to standard ambient temperature, +60F to
+90F (+16C) to +32C), from each operating temperature, the
telescope shall meet the requirements of 3.7.6 through 3.13.1.
3.7.3 Shock. When required, the telescope shall
withstand a total of 18 shock impulses, 3 in each direction of 3
mutually perpendicular axes. Each shock impulse shall be a half
sine wave with a time duration of 6 + 1 milliseconds. The peak
amplitude of each shock impulse shall be 75g's. Subsequent to
shock, the telescope shall show no evidence of physical damage and
shall meet the requirements of 3.7.5 through 3.13.1.
3.7.4 Vibration.
3.7.4.1 Vibration "A". When required the telescope shall
withstand a total of 270 minutes + 5 minutes sweep-cycle
vibration. The vibration shall be applied for 90 minutes 2
minutes along each of the three mutually perpendicular major axes.
A complete sweep-cycle shall consist of vibration from origin (5
hz at 1 inch double amplitude) to mid-point (5g's + 0.5g's at 500
hz) to origin, and shall have a duration of 15 minutes + 1 minute.
Double amplitude shall be constant at 1 inch between 5 hz and 10
hz, and varied with frequency to maintain a constant 5g's 0.5g's
acceleration between 10 hz and 500 hz. Upon completion of
vibration, the telescope shall exhibit no evidence of damage and
shall meet the requirements of 3.7.5 through 3.13.1.
3.7.4.2 Vibration "B". The telescope shall be vibrated in a
vertical plane at a constant frequency of 30 5 cycles per second
with an amplitude of 1/16 inch (1/8 1/64 inch total excursion)
for a period of 5 minutes 15 seconds. Subsequent ot vibration,
there shall be no evidence of damage and the telescope shall meet
the requirements of 3.7.5 through 3.13.1.
3.7.5 Post vibration and shock.
3.7.5.1 Collimation change. The line of sight established
by paragraph 3.6 prior to vibration shall not deviate more than
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