ZOA CTLR DESCRIBED FAILURE OF OCEANIC DATA LINK; IE; ADS AND CPDLC ON 2 CONSECUTIVE DAYS; INDICATING THIS TYPE OF PROB IS ONGOING.

Narrative

AT APPROX XA30; WE BEGAN LOSING ALL DATA LINK CONNECTIONS WITH ACFT OVER THE PACIFIC OCEAN. LOSING DATA LINK CONSTITUTES THE LOSS OF ADS AND CPDLC. WE EFFECTIVELY LOST COMS WITH 50+ AIRPLANES THAT WERE CONNECTED ON DATA LINK AND UNDER ZOA CTL. ONCE IT WAS DETERMINED THAT WE WERE NO LONGER CONNECTED TO THESE PLANES; THE CTLRS HAD TO ATTEMPT TO REESTABLISH SEPARATION ON THE PAIRS THAT WERE SEPARATED USING DISTANCE BASED LONGITUDINAL AND ALSO ATTEMPT TO REESTABLISH COMS WITH THESE ACFT. AFTER SEVERAL ECS (EXTERNAL COMS SEVER) AND CHANNEL SWAPS; THE PROB REMAINED. AT APPROX XC00; ADS AND CPDLC BEGAN WORKING AGAIN. NO EXPLANATION WAS GIVEN FOR THE CAUSE OF THE OUTAGE OR WHAT FIXED IT. THE NEXT DAY; AT APPROX XA00 WE AGAIN LOST DATA LINK COMS ON ALL OF THE FANS EQUIPPED AIRPLANES OVER THE PACIFIC. THE SAME ATTEMPTS WERE MADE TO CORRECT THE PROB THAT WERE MADE THE DAY BEFORE; BUT TO NO AVAIL. SITA WAS CALLED AND REPLIED THAT THEY WERE NOT HAVING ANY PROBS. AROUND XC30; SVC BEGAN TO BE RESTORED. LATER ZOA RECEIVED A FAX FROM SITA STATING THAT THERE WAS AN UNPLANNED OUTAGE FOR 2 1/2 HRS WHICH COINCIDED WITH THE LOSS OF DATA LINK. APPARENTLY; THESE 2 INSTANCES LIKELY HAD DIFFERENT CAUSES. THIS HAS BEEN AN ONGOING ISSUE AT ZOA SINCE 2005 WHEN OCEAN21 WAS TURNED ON. THERE HAVE BEEN SEVERAL UCR'S FILED AND SOME HALF-HEARTED ATTEMPTS TO FIX THE PROB; BUT THIS CONTINUES TO BE A NOT ONLY A SAFETY ISSUE; BUT A SVC ISSUE AS WELL.