Narrative:

On downwind for runway 4R ILS at 5000 ft autoplt on aircraft began sudden bank to approximately 35 degrees due to wake turbulence; autoplt disengaged and unusual attitude recovery accomplished with little or no loss of altitude. ATC advised of wake turbulence encounter. They replied that they had a B757 in front of us that they had descended to 4000 ft. Approach and landing was normal without further incident. Winds were relatively calm and it appears that ATC is vectoring aircraft too close together.

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Original NASA ASRS Text

Title: B737-300 ENCOUNTERED WAKE TURB; ROLLING ACFT INTO APPROX 35 DEGS ANGLE OF BANK.

Narrative: ON DOWNWIND FOR RWY 4R ILS AT 5000 FT AUTOPLT ON ACFT BEGAN SUDDEN BANK TO APPROX 35 DEGS DUE TO WAKE TURBULENCE; AUTOPLT DISENGAGED AND UNUSUAL ATTITUDE RECOVERY ACCOMPLISHED WITH LITTLE OR NO LOSS OF ALTITUDE. ATC ADVISED OF WAKE TURBULENCE ENCOUNTER. THEY REPLIED THAT THEY HAD A B757 IN FRONT OF US THAT THEY HAD DESCENDED TO 4000 FT. APCH AND LNDG WAS NORMAL WITHOUT FURTHER INCIDENT. WINDS WERE RELATIVELY CALM AND IT APPEARS THAT ATC IS VECTORING ACFT TOO CLOSE TOGETHER.

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