Narrative:

I was the pilot flying on approach to runway 25L into lax. We had been cleared to descend via the SEAVU2; cleared ILS 25L (standard operations for lax). The weather was VMC. Winds aloft were approximately 12-15 mph with headwind directly down the inbound approach course. At approximately 15 nm on final approach course; ATC advised a B757 would join the approach ahead of us; entering from left base. I recall the B757 was asked to maintain 250 KTS as long as possible and we were instructed to slow down. We reported the B757 in sight. They rolled wings level on final approach approximately 6 nm ahead of us; speed and spacing looked good. Still approximately 6 nm behind the B757; approximately 10 nm from the airport; approximately 3;500 ft AGL; on the localizer and glideslope (GS); we encountered the wake turbulence of the B757. There were no indications that alerted us of the rough air ahead. Our aircraft rocked left and right; then rolled left approximately 45-60 degrees. I recovered the aircraft manually; leveled the wings; and momentarily maintained altitude to fly above the B757's flight path. I briefed the captain that we would continue the visual approach 'one dot high' on the GS. Other than the momentary roll to the left; the aircraft was stable. We continued without further event flying slightly high on the GS (one dot) and on the localizer centerline with the autopilot; auto-thrust and flight directors all off. Apart from that brief encounter with wake turbulence; the flight and landing were otherwise smooth and uneventful. During deplaning; there were passengers inquiring about the turbulence on final approach. The captain; while standing in the galley/cockpit area bidding farewell to the passengers; explained the turbulence to the passengers asking about it [as] they exited the aircraft. Opinion: the headwinds on final approach were approximately 12-15 mph; and despite our distance behind the B757 being more than adequate (approximately 6nm); I believe the winds were the reason we encountered the wake turbulence at a distance greater than that recommended in the aim; and despite no other FAA literature supporting that theory. At the average approach speed of an A320 approximately 135kts; at approximately 6nm we were approximately 2m40s behind the B757. More detailed wake turbulence study required.

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Original NASA ASRS Text

Title: A320 First Officer reported encountering wake vortex in 6 miles trail of a B757 on approach to LAX that rolled the aircraft up to 60 degrees. Reporter cited wind conditions as probably contributory.

Narrative: I was the pilot flying on approach to RWY 25L into LAX. We had been cleared to descend via the SEAVU2; cleared ILS 25L (standard operations for LAX). The weather was VMC. Winds aloft were approximately 12-15 mph with headwind directly down the inbound approach course. At approximately 15 nm on Final Approach Course; ATC advised a B757 would join the approach ahead of us; entering from left base. I recall the B757 was asked to maintain 250 KTS as long as possible and we were instructed to slow down. We reported the B757 in sight. They rolled wings level on final approach approximately 6 nm ahead of us; speed and spacing looked good. Still approximately 6 nm behind the B757; approximately 10 nm from the airport; approximately 3;500 FT AGL; on the LOC and glideslope (GS); we encountered the wake turbulence of the B757. There were no indications that alerted us of the rough air ahead. Our aircraft rocked left and right; then rolled left approximately 45-60 degrees. I recovered the aircraft manually; leveled the wings; and momentarily maintained altitude to fly above the B757's flight path. I briefed the Captain that we would continue the visual approach 'One Dot High' on the GS. Other than the momentary roll to the left; the aircraft was stable. We continued without further event flying slightly high on the GS (One Dot) and on the LOC centerline with the Autopilot; Auto-Thrust and Flight Directors all off. Apart from that brief encounter with wake turbulence; the flight and landing were otherwise smooth and uneventful. During deplaning; there were passengers inquiring about the turbulence on final approach. The Captain; while standing in the galley/cockpit area bidding farewell to the passengers; explained the turbulence to the passengers asking about it [as] they exited the aircraft. Opinion: The headwinds on Final Approach were approximately 12-15 mph; and despite our distance behind the B757 being more than adequate (approximately 6nm); I believe the winds were the reason we encountered the wake turbulence at a distance greater than that recommended in the AIM; and despite no other FAA literature supporting that theory. At the average approach speed of an A320 approximately 135kts; at approximately 6nm we were approximately 2m40s behind the B757. More DETAILED Wake Turbulence Study Required.

Data retrieved from NASA's ASRS site 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.