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From: | |
Reply To: | TechNet E-Mail Forum. |
Date: | Thu, 30 Jul 1998 15:44:41 -0400 |
Content-Type: | text/plain |
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Vernon,
Per our Reliablity Engineer:
A dropped PWB is considered to be unreliable because the g-forces that the
PWB saw when it hit the ground cannot be correctly determined. If the
g-forces exceeded the maximum allowed for each device any of the following
may have occurred:
1) The glass seal at the IC leads could be cracked and there is no test to
determine this
2) The lids on ICs may no longer be hermetic and there is no test to
determine this
3) Solder joints may be cracked and there is no test to determine this
4) Host of other mechanical failures that cannot be tested for immediately
but may result in functional failures later while in flight.
A dropped PWB may be used as a test card or slave until it exhibits
failures but never in a flight unit.
Regards,
Michael Hilton
Associate Engineer
Orbital
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