Narrative:

Approximately 50 mi south of puerto plata VOR WX deviations were required and approved. Aircraft maintained FL290. Around 30 south of puerto plata we passed the WX and turned back on course. The first officer noticed a widebody transport passing diagonally from right to left at our altitude, crossing in front of us less than 2 mi distant. ZMA was queried and said they had no one but aircraft might be widebody transport Y assigned FL280. The center then said they had the aircraft reading an altitude of FL290. We were still under the control of santo domingo but also in contact with ZMA as per note F on la hi/lo chart 7--note located just west of providenciales. Callback conversation with reporter revealed the following: no follow up inquiry was made by this flight crew. The jumpseat was occupied by an FAA inspector and he promised to make an inquiry and let the flight crew know exactly what caused this incident. Reporter has not heard from the FAA inspector as yet. Everyone in the cockpit made the assumption that the center at santo domingo had assigned the widebody transport FL290 and had coordinated the aircraft to ZMA at FL280. No doubt the deviation around severe WX caused the aircraft to be closer together than their routes, west/O deviation, would have allowed. Reporter stated that the proximity of aircraft was such that they never felt in danger and he emphasized that a near midair collision did not take place.

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Original NASA ASRS Text

Title: WHILE DEVIATING AROUND SEVERE WX, ACR-LGT ENCOUNTERED ACR-WDB AT SAME ALT IN FOREIGN OCEANIC AIRSPACE, RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: APPROX 50 MI S OF PUERTO PLATA VOR WX DEVIATIONS WERE REQUIRED AND APPROVED. ACFT MAINTAINED FL290. AROUND 30 S OF PUERTO PLATA WE PASSED THE WX AND TURNED BACK ON COURSE. THE F/O NOTICED A WDB PASSING DIAGONALLY FROM RIGHT TO LEFT AT OUR ALT, XING IN FRONT OF US LESS THAN 2 MI DISTANT. ZMA WAS QUERIED AND SAID THEY HAD NO ONE BUT ACFT MIGHT BE WDB Y ASSIGNED FL280. THE CENTER THEN SAID THEY HAD THE ACFT READING AN ALT OF FL290. WE WERE STILL UNDER THE CTL OF SANTO DOMINGO BUT ALSO IN CONTACT WITH ZMA AS PER NOTE F ON LA HI/LO CHART 7--NOTE LOCATED JUST W OF PROVIDENCIALES. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: NO FOLLOW UP INQUIRY WAS MADE BY THIS FLT CREW. THE JUMPSEAT WAS OCCUPIED BY AN FAA INSPECTOR AND HE PROMISED TO MAKE AN INQUIRY AND LET THE FLT CREW KNOW EXACTLY WHAT CAUSED THIS INCIDENT. RPTR HAS NOT HEARD FROM THE FAA INSPECTOR AS YET. EVERYONE IN THE COCKPIT MADE THE ASSUMPTION THAT THE CENTER AT SANTO DOMINGO HAD ASSIGNED THE WDB FL290 AND HAD COORDINATED THE ACFT TO ZMA AT FL280. NO DOUBT THE DEVIATION AROUND SEVERE WX CAUSED THE ACFT TO BE CLOSER TOGETHER THAN THEIR ROUTES, W/O DEVIATION, WOULD HAVE ALLOWED. RPTR STATED THAT THE PROX OF ACFT WAS SUCH THAT THEY NEVER FELT IN DANGER AND HE EMPHASIZED THAT A NMAC DID NOT TAKE PLACE.

Data retrieved from NASA's ASRS site as of August 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.