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|  MIL-C-48490B(AR)
4.6.3 Sealing. Pressurize each compartment with dry nitrogen to 4.5
0.5 psig and perform either Sealing A or Sealing B leakage test. After
determination of compliance with the sealing requirement, purge the optical
and transmitter compartments with dry nitrogen at 12 1 psig for not less
than 30 minutes, purge the compartment behind the commnander's panel with dry
nitrogen at 1 0.1 psig for not less than 5 minutes, lower the pressure of
the optical and transmitter compartments to 4.5 0.5 psig and lower the
pressure of the compartment behind the commander's panel to 0.0 0.2 - 0.0
psig. Nitrogen shall be BB-N-411$ type 1$ class 1, grade B with a dewpoint
not greater than -25F.
4.6.3.1 Sealing A. Use item 3 of table x and subject the assembly to the
leakage (immersion) test specified in MIL-STD-81O, method 512.1, procedure
IV. Immersion time shall be not less than 5 minutes.
4.6.3.2 Sealing B. Use item 3 of table X, place the assembly in the
following environment for not less than 2 hours and verify that the pressure
drop is not greater than 0.2 psig.
73 + 2.5F
a. Temperature
50 percent 5 percent
b. Relative humidity
28.5 + 2.0 -3.0 in. H
c. Atmospheric pressure
4.6.4 Environmental tests.
4.6.4.1 Shock.
4.6.4.1.1 Basic design. Use item 2 of table X and subject the assembly
to the shock test specified in MIL-STD-81O, method 516.2, procedure I, figure
516.2.2. Apply three half sine wave shock pulses in each direction along the
three axis Peak amplitude shall be 40 4 g with a time duration of 18 + 3
msec measured at the 10 percent amplitude points. At the conclsusion of this
test, subject the assembly to the performance tests of table VII.
4.6.4.1.2 High inttensity. Use item 2 of table X and subject the assembly
to the shock test specified in MIL-STD-810, method 516.2, procedure IV, figure
516.2-2. Apply three half sine wave shock pulses in each direction along the
three axis. Peak amplitude shall be 100.0 10.0 g with a time duration of
1.5 0.2 msec measured at the 10 percent amplitude points. At the conclusion
of this test, subject the assembly to the performance tests of table VII.
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