Narrative:

Prior to leaving sju my WX briefing included information concerning an area of WX across the oceanic tracks at about my routing midpoint. We were cleared northbound on A300 at FL260 (the only available altitude on this route). As we approached ender (north 27.00, west 68.39) our WX radar showed an extensive line of severe WX with an alignment of nne/ssw. Our conservative estimate was that the line of severe WX extended 100 mi southwest and 100 mi northeast of our position. I attempted to contact commercial radio to report the severity of the WX and advise that we were going to have to deviate to the northeast. I made numerous attempts to contact commercial radio on 8846 to no avail due to extremely poor HF communication resulting from static, etc. We started to deviate to the northeast. As we were on the edge of the severe WX we finally made contact with arinc and advised that we were abeam ender by approximately 50 mi. Commercial radio indicated that they would report our deviation. We lost contact with arinc on HF due to atmospheric interferences. Commercial radio re-established contact with us via SELCAL. We were advised to contact bda control on VHF 128.5. Bda control idented us about 180 mi southwest of bda. At this position we were back toward track. Bda reclred us to priss and then A23 to bdl. Once clear of the WX the flight was routine. In retrospect there was no way we could have penetrated the line of severe WX west/O a serious compromise of safety. Supplemental information from acn 102948: although we had notified commercial radio of the need for deviation, we did not elect to contact bda control on our own. I think our main problem was the line of thunderstorms was moving northeast much faster than we anticipated.

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Original NASA ASRS Text

Title: LGT MAKES WX DEVIATION FAR TO THE EAST OF ASSIGNED OCEANIC AIRWAY.

Narrative: PRIOR TO LEAVING SJU MY WX BRIEFING INCLUDED INFO CONCERNING AN AREA OF WX ACROSS THE OCEANIC TRACKS AT ABOUT MY ROUTING MIDPOINT. WE WERE CLRED NBOUND ON A300 AT FL260 (THE ONLY AVAILABLE ALT ON THIS ROUTE). AS WE APCHED ENDER (N 27.00, W 68.39) OUR WX RADAR SHOWED AN EXTENSIVE LINE OF SEVERE WX WITH AN ALIGNMENT OF NNE/SSW. OUR CONSERVATIVE ESTIMATE WAS THAT THE LINE OF SEVERE WX EXTENDED 100 MI SW AND 100 MI NE OF OUR POS. I ATTEMPTED TO CONTACT COMMERCIAL RADIO TO RPT THE SEVERITY OF THE WX AND ADVISE THAT WE WERE GOING TO HAVE TO DEVIATE TO THE NE. I MADE NUMEROUS ATTEMPTS TO CONTACT COMMERCIAL RADIO ON 8846 TO NO AVAIL DUE TO EXTREMELY POOR HF COM RESULTING FROM STATIC, ETC. WE STARTED TO DEVIATE TO THE NE. AS WE WERE ON THE EDGE OF THE SEVERE WX WE FINALLY MADE CONTACT WITH ARINC AND ADVISED THAT WE WERE ABEAM ENDER BY APPROX 50 MI. COMMERCIAL RADIO INDICATED THAT THEY WOULD RPT OUR DEVIATION. WE LOST CONTACT WITH ARINC ON HF DUE TO ATMOSPHERIC INTERFERENCES. COMMERCIAL RADIO RE-ESTABLISHED CONTACT WITH US VIA SELCAL. WE WERE ADVISED TO CONTACT BDA CTL ON VHF 128.5. BDA CTL IDENTED US ABOUT 180 MI SW OF BDA. AT THIS POS WE WERE BACK TOWARD TRACK. BDA RECLRED US TO PRISS AND THEN A23 TO BDL. ONCE CLR OF THE WX THE FLT WAS ROUTINE. IN RETROSPECT THERE WAS NO WAY WE COULD HAVE PENETRATED THE LINE OF SEVERE WX W/O A SERIOUS COMPROMISE OF SAFETY. SUPPLEMENTAL INFO FROM ACN 102948: ALTHOUGH WE HAD NOTIFIED COMMERCIAL RADIO OF THE NEED FOR DEVIATION, WE DID NOT ELECT TO CONTACT BDA CTL ON OUR OWN. I THINK OUR MAIN PROB WAS THE LINE OF TSTMS WAS MOVING NE MUCH FASTER THAN WE ANTICIPATED.

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.