Aircraft encounters wake turbulence from proceeding B737 on descent into sfo.

Attributes
ACN	342350
Time
Date	199607
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sfo
State Reference	CA
Altitude	msl bound lower : 6000 msl bound upper : 6000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : oak
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent other
Route In Use	arrival other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : commercial pilot : cfi pilot : atp pilot : instrument
Experience	controller non radar : 3 controller supervisory : 1 flight time last 90 days : 180 flight time total : 10000 flight time type : 2000
ASRS Report	342350
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	inflight encounter other
Independent Detector	other flight crewa
Resolutory Action	none taken : insufficient time none taken : unable
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

On approach to sfo in VMC (B737-300) we rolled to the left 3 times in quick succession, up to about 20 degrees. I asked bay approach who we were following and he stated a B737, 7 mi ahead. We did not have the B737 in sight. Callback conversation with reporter revealed the following information: reporter participated in the wake turbulence structured callback study. Reporter was very surprised that he would get that much turbulence following a B737 7 mi ahead. Reporter had no suggestions on what might be done differently so as not to have that same type of encounter.

Original NASA ASRS Text

Title: ACFT ENCOUNTERS WAKE TURB FROM PROCEEDING B737 ON DSCNT INTO SFO.

Narrative: ON APCH TO SFO IN VMC (B737-300) WE ROLLED TO THE L 3 TIMES IN QUICK SUCCESSION, UP TO ABOUT 20 DEGS. I ASKED BAY APCH WHO WE WERE FOLLOWING AND HE STATED A B737, 7 MI AHEAD. WE DID NOT HAVE THE B737 IN SIGHT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR PARTICIPATED IN THE WAKE TURB STRUCTURED CALLBACK STUDY. RPTR WAS VERY SURPRISED THAT HE WOULD GET THAT MUCH TURB FOLLOWING A B737 7 MI AHEAD. RPTR HAD NO SUGGESTIONS ON WHAT MIGHT BE DONE DIFFERENTLY SO AS NOT TO HAVE THAT SAME TYPE OF ENCOUNTER.

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.