An air carrier light transport may have encountered B-757 wake turbulence.

Attributes
ACN	270502
Time
Date	199405
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mem
State Reference	TN
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : mem
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	approach : straight in approach : visual
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 : straight in
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 150 flight time total : 2800 flight time type : 1900
ASRS Report	270502
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	inflight encounter other other anomaly
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

After having been cleared for the visual approach to 18L (mem) we were established on the localizer and descending to intercept the GS approximately 3 mi outside the outer marker. While precisely on the GS, we encountered sufficient wake turbulence to require abrupt and substantial control input and the application of maximum power to egress. We had been cleared to land behind a light twin but a quick review of our FMS wind data revealed a westerly wind of 58 KTS. A 757 had been cleared for runway 18R approximately 4 mins ahead and to our right. 18R extends further north than 18L resulting in a higher glide path relative to aircraft on 18L. This, in combination with the westerly wind blew the wake of the 757 approximately 1200 ft east where we encountered it. Insomuch as we were well outside the outer marker at the time of the encounter, we reacquired the approach and continued, albeit one DOT above the GS, to a normal and uneventful landing. No damage or injuries noted.

Original NASA ASRS Text

Title: AN ACR LTT MAY HAVE ENCOUNTERED B-757 WAKE TURB.

Narrative: AFTER HAVING BEEN CLRED FOR THE VISUAL APCH TO 18L (MEM) WE WERE ESTABLISHED ON THE LOC AND DSNDING TO INTERCEPT THE GS APPROX 3 MI OUTSIDE THE OUTER MARKER. WHILE PRECISELY ON THE GS, WE ENCOUNTERED SUFFICIENT WAKE TURB TO REQUIRE ABRUPT AND SUBSTANTIAL CTL INPUT AND THE APPLICATION OF MAX PWR TO EGRESS. WE HAD BEEN CLRED TO LAND BEHIND A LIGHT TWIN BUT A QUICK REVIEW OF OUR FMS WIND DATA REVEALED A WESTERLY WIND OF 58 KTS. A 757 HAD BEEN CLRED FOR RWY 18R APPROX 4 MINS AHEAD AND TO OUR R. 18R EXTENDS FURTHER N THAN 18L RESULTING IN A HIGHER GLIDE PATH RELATIVE TO ACFT ON 18L. THIS, IN COMBINATION WITH THE WESTERLY WIND BLEW THE WAKE OF THE 757 APPROX 1200 FT E WHERE WE ENCOUNTERED IT. INSOMUCH AS WE WERE WELL OUTSIDE THE OUTER MARKER AT THE TIME OF THE ENCOUNTER, WE REACQUIRED THE APCH AND CONTINUED, ALBEIT ONE DOT ABOVE THE GS, TO A NORMAL AND UNEVENTFUL LNDG. NO DAMAGE OR INJURIES NOTED.

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.