Narrative:

We were flying over the north atlantic on a random route. I believe we had passed 48n015w proceeding to 48n020w. We could see thunderstorms about 80 miles ahead; both visually and on the radar. We called shanwick oceanic stating the 'weather deviation required' and requested 20 miles right of track and that we could be back on track by 48n020w. About 30 miles prior to the weather; shanwick SELCAL'ed us and informed us that our request was not approved. I again advised shanwick that 'deviation was required' and that we would be deviating up to 10 miles right of track. We did deviate around weather and reported back on track at 48n020w. Our maximum deviation never exceeded 8 mile. During the deviation; we did broadcast on 121.5 our flight level; position and deviation. We were following the procedures that are set forth in panel #2 of the atlantic orientation chart. Because shanwick oceanic seemed surprised with what we were doing; I commented to the first officer that they seemed unaware of the procedure. I then did a quick review of the orientation chart just to make sure that the procedure hadn't changed.

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Original NASA ASRS Text

Title: B767 flight crew reports deviating around weather on the North Atlantic after being denied permission to do so by Shanwick Oceanic control.

Narrative: We were flying over the North Atlantic on a random route. I believe we had passed 48N015W proceeding to 48N020W. We could see thunderstorms about 80 miles ahead; both visually and on the radar. We called Shanwick Oceanic stating the 'Weather Deviation Required' and requested 20 miles RIGHT of track and that we could be back on track by 48N020W. About 30 miles prior to the weather; Shanwick SELCAL'ed us and informed us that our request was not approved. I again advised Shanwick that 'Deviation Was Required' and that we would be deviating up to 10 miles RIGHT of track. We did deviate around weather and reported back on track at 48N020W. Our maximum deviation never exceeded 8 mile. During the deviation; we did broadcast on 121.5 our flight level; position and deviation. We were following the procedures that are set forth in Panel #2 of the ATLANTIC ORIENTATION CHART. Because Shanwick Oceanic seemed surprised with what we were doing; I commented to the F/O that they seemed unaware of the procedure. I then did a quick review of the orientation chart just to make sure that the procedure hadn't changed.

Data retrieved from NASA's ASRS site as of April 2012 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.