An MD88 encounters the wake of a B777 reported 8 miles ahead.

Attributes
ACN	737145
Time
Date	200704
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : atl.airport
State Reference	GA
Altitude	msl single value : 9500
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	tracon : a80.tracon
Operator	common carrier : air carrier
Make Model Name	MD-88
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : intermediate altitude
Route In Use	arrival other
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : a80.tracon
Operator	common carrier : air carrier
Make Model Name	B777 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : intermediate altitude
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 8000 flight time type : 1300
ASRS Report	737145
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	inflight encounter : wake turbulence other anomaly
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : took evasive action flight crew : regained aircraft control
Supplementary
Problem Areas	Environmental Factor
Primary Problem	Environmental Factor

Narrative:

Severe wake encounter while 8 NM (radar confirmed) of B777; both at 180 KTS assigned. Aircraft was on autoplt when encountered. Both aircraft were descending on downwind RNAV arrival. Roll was at 45 degrees and increasing when manual control was reestablished. This is a significant wake encounter and may have resulted in temporary loss of control if the first officer had not been quick to disconnect the autoplt and reverse roll. Aircraft took approximately 2 to 3 seconds to respond. Aircraft weight was approximately 125000 pounds. Winds at altitude were directly on the tail at approximately 40 KTS.

Original NASA ASRS Text

Title: AN MD88 ENCOUNTERS THE WAKE OF A B777 RPTED 8 MILES AHEAD.

Narrative: SEVERE WAKE ENCOUNTER WHILE 8 NM (RADAR CONFIRMED) OF B777; BOTH AT 180 KTS ASSIGNED. ACFT WAS ON AUTOPLT WHEN ENCOUNTERED. BOTH ACFT WERE DESCENDING ON DOWNWIND RNAV ARR. ROLL WAS AT 45 DEGS AND INCREASING WHEN MANUAL CTL WAS REESTABLISHED. THIS IS A SIGNIFICANT WAKE ENCOUNTER AND MAY HAVE RESULTED IN TEMPORARY LOSS OF CONTROL IF THE FO HAD NOT BEEN QUICK TO DISCONNECT THE AUTOPLT AND REVERSE ROLL. ACFT TOOK APPROX 2 TO 3 SECONDS TO RESPOND. ACFT WT WAS APPROX 125000 LBS. WINDS AT ALT WERE DIRECTLY ON THE TAIL AT APPROX 40 KTS.

Data retrieved from NASA's ASRS site as of January 2009 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.