An emb-145 flight crew encountered wake turbulence on approach behind a B777.

Attributes
ACN	793336
Time
Date	200806
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 5000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : zzz.tracon
Operator	common carrier : air carrier
Make Model Name	EMB ERJ 145 ER&LR
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	arrival : on vectors
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : zzz.tracon
Make Model Name	B777 Undifferentiated or Other Model
Flight Phase	descent : approach
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 : 16500 flight time type : 3500
ASRS Report	793336
Events
Anomaly	inflight encounter : wake turbulence
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Supplementary
Problem Areas	Environmental Factor
Primary Problem	Environmental Factor

Narrative:

About 10 minutes from landing while on vectors to final at 5000 ft MSL we encountered a sharp moderate roll to starboard approximately 20 degrees aob followed by a second; lesser intensity roll of about 10 degrees. The encounter was while level and in clear air. I was certain no damage was done to the aircraft but the surprising suddenness of the roll and the aob caused me to be concerned enough to check on my flight attendant. She stated she'd banged her jaw and side of head against the overhead lighting bank on the port side of the aircraft (the lights over the 'a' seat row); but felt okay at the moment. We landed without further incident. Wake turbulence off aircraft of unknown type. Suspect B777 which landed 5-7 miles ahead on runway xxc.

Original NASA ASRS Text

Title: AN EMB-145 FLT CREW ENCOUNTERED WAKE TURBULENCE ON APCH BEHIND A B777.

Narrative: ABOUT 10 MINUTES FROM LNDG WHILE ON VECTORS TO FINAL AT 5000 FT MSL WE ENCOUNTERED A SHARP MODERATE ROLL TO STARBOARD APPROX 20 DEGS AOB FOLLOWED BY A SECOND; LESSER INTENSITY ROLL OF ABOUT 10 DEGS. THE ENCOUNTER WAS WHILE LEVEL AND IN CLEAR AIR. I WAS CERTAIN NO DAMAGE WAS DONE TO THE ACFT BUT THE SURPRISING SUDDENNESS OF THE ROLL AND THE AOB CAUSED ME TO BE CONCERNED ENOUGH TO CHECK ON MY FLT ATTENDANT. SHE STATED SHE'D BANGED HER JAW AND SIDE OF HEAD AGAINST THE OVERHEAD LIGHTING BANK ON THE PORT SIDE OF THE ACFT (THE LIGHTS OVER THE 'A' SEAT ROW); BUT FELT OKAY AT THE MOMENT. WE LANDED WITHOUT FURTHER INCIDENT. WAKE TURBULENCE OFF ACFT OF UNKNOWN TYPE. SUSPECT B777 WHICH LANDED 5-7 MILES AHEAD ON RWY XXC.

Data retrieved from NASA's ASRS site as of May 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.