Well, Just for my two cents, 40,000 ft equates to roughly 1/5 the pressure at sea level or almost 3 lbs/in^2 absolute compared against 14.7 lbs/in^2 at sea level absolute. That leaves any type of plug or wall structure of the capacitor having to withstand 11 lbs/in^2 across it.
Also, the capacitor or even a transformer may have fluid inside and leak. It also may involve a chip ingassing humidity once it's back on the ground. Why? Assume typical temp at 40,000 ft is nominally -70 degrees F. Within a matter of minutes the plane could be on the ground in some tropical area. Condensation occurs on the chip, water forms, ingassing occurs and now you've got a saturated chip. Regards, Doug [email protected] wrote: > > There is also an FAA? limit on the magnetic properties of air > shipments. The gauss from the package must be within a stated > maximum to avoid interference with navigational instrumentation. > Even a concentrated shipment of small motors can exceed the > limit due to the magnetized elements within. > > It has been five years since I was in EMC so I can't cite the > actual standard or regulation. > > Don't know if this is what you were looking for...... > > George Alspaugh > Product Safety > > Please respond to rbusche%[email protected] > > To: emc-pstc%[email protected] > cc: (bcc: George Alspaugh) > bcc: George Alspaugh > Subject: Altitude > > This is not a safety or EMI question, but because this group has such > broad backgrounds and diversity I am hoping that someone can comment. > > I have been asked by one of our customers to ensure that our equipment > is capable of being shipped in an un-pressurized aircraft for altitudes > of 30K to 40 K feet. This is a non operational requirement, but are > there other concerns I should be aware of? I recall hearing that some > commercial grade electrolytic could explode at high altitudes. > > Any comments or suggestions greatly appreciated. > > Rick Busche > Evans & Sutherland > Salt Lake City, Utah > [email protected]
