Narrative:

Following an airbus on a visual 3 mi behind. Encountered wake and rolled more than 45 degrees. Disconnected autoplt and used full control authority to level the wings. Slowed to increase spacing. We asked what kind of airbus and was told an A321. Spacing was good. He was at 4000 ft and passed through our altitude 3 miles ahead in fairly calm conditions. We do not know how heavy he was; but maybe more spacing behind A321 would be better.

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Original NASA ASRS Text

Title: PASSING THROUGH THE WAKE OF AN A321 CAUSED MORE THAN 45 DEGS OF ROLL THAT REQUIRED THE USE OF FULL CONTROL AUTHORITY BY A B737 CREW DURING RECOVERY.

Narrative: FOLLOWING AN AIRBUS ON A VISUAL 3 MI BEHIND. ENCOUNTERED WAKE AND ROLLED MORE THAN 45 DEGS. DISCONNECTED AUTOPLT AND USED FULL CONTROL AUTHORITY TO LEVEL THE WINGS. SLOWED TO INCREASE SPACING. WE ASKED WHAT KIND OF AIRBUS AND WAS TOLD AN A321. SPACING WAS GOOD. HE WAS AT 4000 FT AND PASSED THROUGH OUR ALTITUDE 3 MILES AHEAD IN FAIRLY CALM CONDITIONS. WE DO NOT KNOW HOW HEAVY HE WAS; BUT MAYBE MORE SPACING BEHIND A321 WOULD BE BETTER.

Data retrieved from NASA's ASRS site as of May 2009 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.