Narrative:

While cruising at FL350 aircraft encountered severe turbulence. Was unable to control aircraft altitude and heading. Advised center of situation. Turbulence lasted from near bancs intersection to past 46N, 502, estimated to most severe turbulence (when aircraft was close to uncontrollable) lasted approximately 5 mins.

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Original NASA ASRS Text

Title: WDB TRANS-ATLANTIC FLT ENCOUNTERS SUSTAINED SEVERE TURBULENCE AT 35000', CAUSING LOSS OF CONTROL.

Narrative: WHILE CRUISING AT FL350 ACFT ENCOUNTERED SEVERE TURB. WAS UNABLE TO CONTROL ACFT ALT AND HDG. ADVISED CENTER OF SITUATION. TURB LASTED FROM NEAR BANCS INTXN TO PAST 46N, 502, ESTIMATED TO MOST SEVERE TURB (WHEN ACFT WAS CLOSE TO UNCONTROLLABLE) LASTED APPROX 5 MINS.

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.