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|  MILB-48447A(AR)
AMENDMENT 2
PAGE 3
3.4.4, Delete and substitute:
3.4.4 Vibration "B". Vibration shall be applied along each of
the three mutually perpendicular axes of the body assembly. The
vibration shall be sinusoidal as follows:
a. At a frequency of 5 Hertz (Hz), the acceleration shall be
1.0 G + 10%.
b. During a frequency sweep of 5 to 500 Hz, maintain constant
acceleration of 1.0 G + 10%.
c. During a frequency sweep of 500 to 5 Hz, maintain constant
acceleration of 1.0 G + 10%
d. At 5 Hz, acceleration shall be 1.0 G + 10%.
The frequency of applied vibration shall be swept logarithmically
in 15 minutes + 1 minute sweep cycles for a total of 15 minutes +
1 minute along each of the three mutually perpendicular axes
(total Vibration time 45 minutes + 3 minutes). The body assembly
shall shown no evidence of physical failure subsequent to
vibration. Following the vibration test the body assembly shall
meet therequirements of 3.2and 3.5 through 3.17.4 inclusive."
3.4.5, Delete and substitute:
3.4.5 S h o c k The body assembly shall be subjected to 24
cumulative shock consisting of three each at 35 G's + 10%, then
20 G's + 10% applied in each direction along each of the two
mutually perpendicular horizontal axes(all four sides). The
shock pulse shall have a half sine wave with a time duration of 3
+.2 milliseconds. The body assembly shall also be subjected to
six cumulative shocks consisting of three each at 35 G's + 10%,
then 20 G's 10% applied in one direction along the vertical axis
(normal operating position of the body assembly only). The shock
pulse shall have a half sine wave with a time duration of 18 + 3
milliseconds. The body assembly shall show no evidence of
physical failure subsequent to shock. Following the shock test,
the body assembly shall meet the requirements of 3.2 and 3.5
through 3.17.4 inclusive."
PAGE 4
*
3.6, Delete and substitute:
"3.6 Sealing. The body assembly shall show no evidence of
leakage in excess of 0.1 pound per square inch (psi) when
subjected to an internal pressure of 5 + 0.10 psi for a minimum of
1 hour. The interior atmosphere of the accepted body assembly
shall contain nitrogen having a dew point at least as low as minus
25F at atmospheric pressure. The body assembly shall then be
sealed with the dry nitrogen specified to an internal pressure of
between 0.25 and 0.50 psig."
2
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