Downloaded from https://www.everyspec.com ) MIL-STD-81OC b. Using suitable wooden fences, constrain the,vehicular, or simulated, adapter plate to a horizontal motion of not more than 2 inches in any lateral direction. 4.6.10.2.3 Performance of test Step 1 - Preuare the test item in accordance with General Require- ments, 3.2, securing the test item to the vehicular, or simulated, adapter plate and placing on the package tester with the constraints outlined in 4.6.10.2.2. If the test item weighs over 200 pounds, simulated adapter plate approved by the procuring agency shall be used.
Step 2 - Attach an accelerometer as close as ,possibleto the point of test item attachment .torecord the shock transmitted to the test item. Step 3 - Adjust the package tester, shafts in phase and table operating in a vertical linear mode, to a speed such that the average value of the random accelerationpeaks shall be 7.5 f2.5g’s. Measure this input with an accurate measuring or recording system at the output of a band pass filter. The filter band pass shall be 0.2 to 100 Hz and the attenuation slope shall be 12 to , 18 dB per octave at the 3-dB down point.
Due to the random nature of the input, pulses greater than 10g’s can be expected to occur, however, if they are infre- quent, they need not be used in calculating the aver- age. Perform the test for a total,of 3 hours. At the end of each 3/4-hour period, rotate the adapter plate and test item 90 degrees each time in the same direction. Step 4 - At the end of the 3-hour period, operate and inspect the test item in accordance with General Requirements, 3.2. Then inspect the test item as specified in General Requirements, 3.2. 4.6.11 Procedure X (Former 4.15). Equipment transported as secured cargo. Proceed the same as in 4.5.1.3 with the unpackaged test item secured to the vibrator table.
The test level and time schedules shall be in accordance with figure 514.2-7 and table 514.2-VII. The test item will not be operated during ~ibration. 4.6.12 Procedure XI (Former 4.16). Equipment transported as loose cargo. 514.2-17 t METHOD 514.2