Wake turbulence encounter behind 757 landing on parallel runway.

Attributes
ACN	288796
Time
Date	199411
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sfo
State Reference	CA
Altitude	msl bound lower : 6000 msl bound upper : 7000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : oak
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	approach : visual arrival other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	approach : visual arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 220 flight time total : 19000 flight time type : 4500
ASRS Report	288796
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : instrument pilot : commercial
Events
Anomaly	inflight encounter other other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : regained aircraft control other
Consequence	faa : reviewed incident with flight crew
Supplementary
Air Traffic Incident	other

Narrative:

Strong wake turbulence following B757 on visual approach to sfo, required full aileron to maintain control. Position -- inbound Q B approach sfo runway 28R. 095 degree radial sfo at or above profile about 18 DME. Altitude 7000-6000 ft descending, 160 KIAS assigned, flaps 15 degrees, nice day, workload low. WX -- clear, visibility 20 plus, ATIS wind calm. Event -- with B757 on tip toe approach to runway 28L. 5-7 mi ahead, aircraft began a moderate rate roll (cannot recall direction) requiring full aileron input to control aircraft roll. Aircraft continued to roll. Large thrust increase applied, some rudder and leveled off. Regained immediate control. Requested and received approval for south turns. Check tower winds (140/about 6 KTS). Requested runway 28L (upwind) and landed. Had aviation safety inspection (airworthiness). After landing: advised bat TRACON to 1) describe situation and south turns and runway 28L request. 2) re-emphasize pilots concerns regarding B757 wake turbulence. 3) suggest staggering approach aircraft so that aircraft immediately following B757 is on the upwind side. Suggestions: 1) involve ATC more regarding our desire to be upwind (this incident ATIS report calm but tower report 140/6 KTS) B-757. 2) re-evaluate aim for criteria for wake turbulence separation. We were never closer than 5 mi on TCASII.

Original NASA ASRS Text

Title: WAKE TURB ENCOUNTER BEHIND 757 LNDG ON PARALLEL RWY.

Narrative: STRONG WAKE TURB FOLLOWING B757 ON VISUAL APCH TO SFO, REQUIRED FULL AILERON TO MAINTAIN CTL. POS -- INBOUND Q B APCH SFO RWY 28R. 095 DEG RADIAL SFO AT OR ABOVE PROFILE ABOUT 18 DME. ALT 7000-6000 FT DSNDING, 160 KIAS ASSIGNED, FLAPS 15 DEGS, NICE DAY, WORKLOAD LOW. WX -- CLR, VISIBILITY 20 PLUS, ATIS WIND CALM. EVENT -- WITH B757 ON TIP TOE APCH TO RWY 28L. 5-7 MI AHEAD, ACFT BEGAN A MODERATE RATE ROLL (CANNOT RECALL DIRECTION) REQUIRING FULL AILERON INPUT TO CTL ACFT ROLL. ACFT CONTINUED TO ROLL. LARGE THRUST INCREASE APPLIED, SOME RUDDER AND LEVELED OFF. REGAINED IMMEDIATE CTL. REQUESTED AND RECEIVED APPROVAL FOR S TURNS. CHK TWR WINDS (140/ABOUT 6 KTS). REQUESTED RWY 28L (UPWIND) AND LANDED. HAD AVIATION SAFETY INSPECTION (AIRWORTHINESS). AFTER LNDG: ADVISED BAT TRACON TO 1) DESCRIBE SIT AND S TURNS AND RWY 28L REQUEST. 2) RE-EMPHASIZE PLTS CONCERNS REGARDING B757 WAKE TURB. 3) SUGGEST STAGGERING APCH ACFT SO THAT ACFT IMMEDIATELY FOLLOWING B757 IS ON THE UPWIND SIDE. SUGGESTIONS: 1) INVOLVE ATC MORE REGARDING OUR DESIRE TO BE UPWIND (THIS INCIDENT ATIS RPT CALM BUT TWR RPT 140/6 KTS) B-757. 2) RE-EVALUATE AIM FOR CRITERIA FOR WAKE TURB SEPARATION. WE WERE NEVER CLOSER THAN 5 MI ON TCASII.

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.