Narrative:

ZLA suffered a circuit breaker failure that necessitated shutting off our power to our cooling system. When we shut the power off, after about 45 mins (on oct/xa/96 at XX30 local), ZLA lost most radio, interphone, and radar data. We had an operational deviation with ZAB. Due to having to shut off our equipment cooling system, portions of our computer system became overheated. One sector had display problems the next morning. We subsequently suffered a loss of 6 other control position by the failure of yet another component(south) in our system. This failure lasted 5 days, only being fixed early this morning (oct/xh/96). Controllers were forced to work with sectors 'combined' up, resulting in an increased workload, decreased safety margins, and greatly increased controller fatigue. Attempts to fix the problem caused an additional 7 sectors to fail on oct/xg/96. Callback conversation with reporter revealed the following information: reporter stated that since the final repairs have been completed, no other outages related to this anomaly have occurred. Reporter claims that during the outage facility environmental technicians discovered that some equipment should not have been coupled to the essential buss which caused some of the failures. These circuits should have been connected to the main power buss.

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Original NASA ASRS Text

Title: ZLA CTLR RPTS THAT A CIRCUIT BREAKER FAILURE CAUSED A COOLING PROB WHICH LED TO MULTIPLY SECTOR FAILURES. AN OPDEV OCCURRED WITH ZAB DURING THE INITIAL OUTAGE.

Narrative: ZLA SUFFERED A CIRCUIT BREAKER FAILURE THAT NECESSITATED SHUTTING OFF OUR PWR TO OUR COOLING SYS. WHEN WE SHUT THE PWR OFF, AFTER ABOUT 45 MINS (ON OCT/XA/96 AT XX30 LCL), ZLA LOST MOST RADIO, INTERPHONE, AND RADAR DATA. WE HAD AN OPDEV WITH ZAB. DUE TO HAVING TO SHUT OFF OUR EQUIP COOLING SYS, PORTIONS OF OUR COMPUTER SYS BECAME OVERHEATED. ONE SECTOR HAD DISPLAY PROBS THE NEXT MORNING. WE SUBSEQUENTLY SUFFERED A LOSS OF 6 OTHER CTL POS BY THE FAILURE OF YET ANOTHER COMPONENT(S) IN OUR SYS. THIS FAILURE LASTED 5 DAYS, ONLY BEING FIXED EARLY THIS MORNING (OCT/XH/96). CTLRS WERE FORCED TO WORK WITH SECTORS 'COMBINED' UP, RESULTING IN AN INCREASED WORKLOAD, DECREASED SAFETY MARGINS, AND GREATLY INCREASED CTLR FATIGUE. ATTEMPTS TO FIX THE PROB CAUSED AN ADDITIONAL 7 SECTORS TO FAIL ON OCT/XG/96. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT SINCE THE FINAL REPAIRS HAVE BEEN COMPLETED, NO OTHER OUTAGES RELATED TO THIS ANOMALY HAVE OCCURRED. RPTR CLAIMS THAT DURING THE OUTAGE FACILITY ENVIRONMENTAL TECHNICIANS DISCOVERED THAT SOME EQUIP SHOULD NOT HAVE BEEN COUPLED TO THE ESSENTIAL BUSS WHICH CAUSED SOME OF THE FAILURES. THESE CIRCUITS SHOULD HAVE BEEN CONNECTED TO THE MAIN PWR BUSS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.