All flights in the United States are grounded until further notice,

[Brad Sallows]

As I wrote earlier the disadvantage to centralization. One group of cables in a remote location and it took down the entire system. I would assign some of the blame to the people who originally designed it without building in the ability to change equipment and wiring harnesses out and verify acceptance in total isolation.

How do you know they didn't design it that way and that the people doing the upgrade didn't 100% understand what they were upgrading?

 

[YZT580]

How do you know they didn't design it that way and that the people doing the upgrade didn't 100% understand what they were upgrading?

Don't for sure but I am relying on history. Every failure in the U.S. going back to the late 70s' affected more than just the unit where the failure occurred. Their flight planning computer was centralized in Washington which I believe is the system that failed here as a/c were still being displayed and it appears that if they were airborne and correlated than the information on that flight stayed with it so no display problems. Communications weren't an issue so that only leaves flight planning. This also wasn't the first wire replacement to be done. Just like Bell and their fiberoptic replacement they have been going place to place for years. It is possible that the tech screwed up and left the system live while he did the substitute but it doesn't seem likely as part of any system that I have dealt with there is a system check to ensure continuity and unplugging something immediately turns the green light red. Time will tell but whether the FAA will tell anyone else remains to be seen (at least until the law suits hit)

 

[The Bread Guy]

How do you know they didn't design it that way and that the people doing the upgrade didn't 100% understand what they were upgrading?

Not to mention sometimes plugging new shit into older shit with a different "new, improved" interface may not always go according to plan?