MD80 flight crew encounters wake turbulence during climb to altitude from preceding B777.

Attributes
ACN	707850
Time
Date	200608
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : djb.vortac
State Reference	OH
Altitude	msl single value : 36500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	MD-80 Series (DC-9-80) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise : enroute altitude change
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zob.artcc
Operator	common carrier : air carrier
Make Model Name	B777 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain
Qualification	pilot : atp
ASRS Report	707850
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	inflight encounter : wake turbulence
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : exited adverse environment flight crew : regained aircraft control
Supplementary
Problem Areas	Aircraft Environmental Factor
Primary Problem	Environmental Factor

Narrative:

We were climbing from FL350 to FL370. A B777 had previously passed us at FL370. We were on the same flight path. At FL365 we encountered his wake turbulence and rolled about 30 to 45 degrees. The total encounter was about 15 to 20 seconds long with at times strong buffeting. My first officer had to fight the controls and the rolling moment to stay in control. No injuries. Reminded passenger that this is why we ask them to wear their seatbelts. The key to this encounter -- we never would have anticipated this because the B777 was 12 miles ahead of us.callback conversation with reporter revealed the following information: reporter stated that they did not expect any encounter as the B777 was well past their position. The wind was a quartering tailwind of approximately 50 KTS. The aircraft was on the exact same course as the B777 and approximately 12 NM past the reporter's aircraft prior to the climb being initiated to the next altitude. As the climb was initiated at approximately FL365; the aircraft began to shudder several times and then the roll was quite violent to approximately 45 degrees; requiring full aileron deflection to bring it back to flight level. Reporter stated that both he and first officer were caught by surprise by the encounter as they actually watched the other aircraft's distance on the TCAS and assumed that was sufficient.

Original NASA ASRS Text

Title: MD80 FLT CREW ENCOUNTERS WAKE TURB DURING CLB TO ALT FROM PRECEDING B777.

Narrative: WE WERE CLBING FROM FL350 TO FL370. A B777 HAD PREVIOUSLY PASSED US AT FL370. WE WERE ON THE SAME FLT PATH. AT FL365 WE ENCOUNTERED HIS WAKE TURB AND ROLLED ABOUT 30 TO 45 DEGS. THE TOTAL ENCOUNTER WAS ABOUT 15 TO 20 SECONDS LONG WITH AT TIMES STRONG BUFFETING. MY FO HAD TO FIGHT THE CTLS AND THE ROLLING MOMENT TO STAY IN CONTROL. NO INJURIES. REMINDED PAX THAT THIS IS WHY WE ASK THEM TO WEAR THEIR SEATBELTS. THE KEY TO THIS ENCOUNTER -- WE NEVER WOULD HAVE ANTICIPATED THIS BECAUSE THE B777 WAS 12 MILES AHEAD OF US.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THEY DID NOT EXPECT ANY ENCOUNTER AS THE B777 WAS WELL PAST THEIR POSITION. THE WIND WAS A QUARTERING TAILWIND OF APPROX 50 KTS. THE ACFT WAS ON THE EXACT SAME COURSE AS THE B777 AND APPROX 12 NM PAST THE RPTR'S ACFT PRIOR TO THE CLB BEING INITIATED TO THE NEXT ALT. AS THE CLB WAS INITIATED AT APPROX FL365; THE ACFT BEGAN TO SHUDDER SEVERAL TIMES AND THEN THE ROLL WAS QUITE VIOLENT TO APPROX 45 DEGS; REQUIRING FULL AILERON DEFLECTION TO BRING IT BACK TO FLT LEVEL. RPTR STATED THAT BOTH HE AND FO WERE CAUGHT BY SURPRISE BY THE ENCOUNTER AS THEY ACTUALLY WATCHED THE OTHER ACFT'S DISTANCE ON THE TCAS AND ASSUMED THAT WAS SUFFICIENT.

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.