The common practice I refer to in aerospace is that of attenuating vibration levels for equipment items weighing over a threshold weight, typically about 80 lbs. The heavier the item, the more attenuation is allowed until the threshold floor of about 25% of max level is reached. This means that if the Environmental Criteria Document specifies a base input of 15 Grms with a peak PSD of .15 G^2/Hz, then a heavy item might only be tested to half of the peak level, .075 G^2/Hz with attendant Grms.
If I now have an SRS from say, a catapult launch and arrested landing scenario, would it appropriate to apply inertia relief to the shock levels for heavy items as well?
Designing engine mounts to carrier shock loads without the benefit of inertial relief would add weight to the structure.
Thanks.
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