Narrative:

I was first officer, PF. We were receiving radar vectors after passing kains intersection to mia. A visual approach expected to runway 12. Local WX approximately 3000 ft scattered, 75 degrees F, winds 120 degrees 18 KTS with LLWS reports. At 8000 ft I was hand flying in VMC. An aircraft was observed on TCASII and then visually to be approximately 7-8 mi at 8000 ft MSL. We were on arrival at kains and given heading 270 degrees. In the turn we encountered moderate turbulence with slight altitude fluctuations and rapid roll from a 20 degree bank turn to approximately 45 degrees. Control was never lost, turn was completed. Captain asked mia approach what type aircraft we were following and the controller advised a B757. We advised him of wake turbulence encounter. Controller said we were 7 mi in trail. We then received delaying vectors for additional spacing as aircraft was conducting ILS to runway 09L. Flight continued without further incident. During deplaning, a passenger commented about the 'big bump.' even though I have followed many B757's on approach without incident I feel controllers should notify aircraft that are within 10 mi in trail of all B757's. It is obvious the B757 has a wake turbulence problem. I am curious that not much news has come from boeing on possible remedies to eliminate the problem (as much as feasible). Retrofit may not be financially an option but I hope some research is being conducted. When made aware I am following a B757 I will continue to stay upwind, above GS and land long when at all possible but I need to know he's there without his wake turbulence being the only calling card. Callback conversation with reporter revealed the following information: callback in conjunction with wake turbulence special study. Reporter flight crew was surprised at the rate of roll from 20 degree bank to instantly 45 degree bank due to preceding B757. Flight crew had aircraft both visually and on TCASII, but didn't know it was a B757. When ATC was questioned about the preceding aircraft type, the controller was surprised that they had experienced the wake turbulence because reporter was 7 mi in trail of the B757. Approach control then provided greater spacing for reporter with radar vectors. Besides the instant bank increase, no further control problems occurred. Several passenger made comments when deplaning about the 'big bump.'

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Original NASA ASRS Text

Title: ACFT 7 MI IN TRAIL OF B757, SAME ALT, EXPERIENCED WAKE TURB AND RAPID ROLL FROM A 20 DEG BANK TO 45 DEG BANK. ACFT IN COMPLETE CTL AND INSTANTLY RETURNED TO NORMAL FLT.

Narrative: I WAS FO, PF. WE WERE RECEIVING RADAR VECTORS AFTER PASSING KAINS INTXN TO MIA. A VISUAL APCH EXPECTED TO RWY 12. LCL WX APPROX 3000 FT SCATTERED, 75 DEGS F, WINDS 120 DEGS 18 KTS WITH LLWS RPTS. AT 8000 FT I WAS HAND FLYING IN VMC. AN ACFT WAS OBSERVED ON TCASII AND THEN VISUALLY TO BE APPROX 7-8 MI AT 8000 FT MSL. WE WERE ON ARR AT KAINS AND GIVEN HEADING 270 DEGS. IN THE TURN WE ENCOUNTERED MODERATE TURB WITH SLIGHT ALT FLUCTUATIONS AND RAPID ROLL FROM A 20 DEG BANK TURN TO APPROX 45 DEGS. CTL WAS NEVER LOST, TURN WAS COMPLETED. CAPT ASKED MIA APCH WHAT TYPE ACFT WE WERE FOLLOWING AND THE CTLR ADVISED A B757. WE ADVISED HIM OF WAKE TURB ENCOUNTER. CTLR SAID WE WERE 7 MI IN TRAIL. WE THEN RECEIVED DELAYING VECTORS FOR ADDITIONAL SPACING AS ACFT WAS CONDUCTING ILS TO RWY 09L. FLT CONTINUED WITHOUT FURTHER INCIDENT. DURING DEPLANING, A PAX COMMENTED ABOUT THE 'BIG BUMP.' EVEN THOUGH I HAVE FOLLOWED MANY B757'S ON APCH WITHOUT INCIDENT I FEEL CTLRS SHOULD NOTIFY ACFT THAT ARE WITHIN 10 MI IN TRAIL OF ALL B757'S. IT IS OBVIOUS THE B757 HAS A WAKE TURB PROB. I AM CURIOUS THAT NOT MUCH NEWS HAS COME FROM BOEING ON POSSIBLE REMEDIES TO ELIMINATE THE PROB (AS MUCH AS FEASIBLE). RETROFIT MAY NOT BE FINANCIALLY AN OPTION BUT I HOPE SOME RESEARCH IS BEING CONDUCTED. WHEN MADE AWARE I AM FOLLOWING A B757 I WILL CONTINUE TO STAY UPWIND, ABOVE GS AND LAND LONG WHEN AT ALL POSSIBLE BUT I NEED TO KNOW HE'S THERE WITHOUT HIS WAKE TURB BEING THE ONLY CALLING CARD. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: CALLBACK IN CONJUNCTION WITH WAKE TURB SPECIAL STUDY. RPTR FLC WAS SURPRISED AT THE RATE OF ROLL FROM 20 DEG BANK TO INSTANTLY 45 DEG BANK DUE TO PRECEDING B757. FLC HAD ACFT BOTH VISUALLY AND ON TCASII, BUT DIDN'T KNOW IT WAS A B757. WHEN ATC WAS QUESTIONED ABOUT THE PRECEDING ACFT TYPE, THE CTLR WAS SURPRISED THAT THEY HAD EXPERIENCED THE WAKE TURB BECAUSE RPTR WAS 7 MI IN TRAIL OF THE B757. APCH CTL THEN PROVIDED GREATER SPACING FOR RPTR WITH RADAR VECTORS. BESIDES THE INSTANT BANK INCREASE, NO FURTHER CTL PROBS OCCURRED. SEVERAL PAX MADE COMMENTS WHEN DEPLANING ABOUT THE 'BIG BUMP.'

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.