Crew had engine failure in ZID class a airspace.

Attributes
ACN	517143
Time
Date	200107
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : ind.airport
State Reference	IN
Altitude	msl single value : 31000
Environment
Flight Conditions	IMC
Weather Elements	Ice
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zid.artcc
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : instrument pilot : multi engine pilot : atp
Experience	flight time last 90 days : 200 flight time total : 14600 flight time type : 1000
ASRS Report	517143
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical other anomaly other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : engine vibration sensor other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance flight crew : diverted to another airport flight crew : declared emergency flight crew : landed in emergency condition
Consequence	other other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Cruise at FL310, first officer and I noticed an acrid smell -- dirty socks. 3 mins later, the left engine vibration indicator indicated 5.0 (maximum high) with vibrations but no other indication. Right engine normal, anti-ice on. Smell increased. Oxygen mask -- both pilots on. Vibration ceased with thrust levers pulled to idle for descent. 3 mins later, level at 13000 ft in clear. Anti-ice off, power up, left engine vibration returned (5.0). Smell throughout cabin. No smoke. Retarded thrust levers to idle. Vibration both engines normal, but left engine noise. Smell cleared. Checklists accomplished. In descent to approach at ind runway 23L, flight attendant reported streams of flame out of back of left engine. Flew single engine approach with left engine in idle. Uneventful landing at ind, except 10000 pounds overweight. Taxied to gate after fire personnel checked aircraft/left engine. Emergency declared departing 13000 ft. All engine indications on both engines normal except vibration indicator on left engine at FL310 cruise and when power was advanced at 13000 ft.

Original NASA ASRS Text

Title: CREW HAD ENG FAILURE IN ZID CLASS A AIRSPACE.

Narrative: CRUISE AT FL310, FO AND I NOTICED AN ACRID SMELL -- DIRTY SOCKS. 3 MINS LATER, THE L ENG VIBRATION INDICATOR INDICATED 5.0 (MAX HIGH) WITH VIBRATIONS BUT NO OTHER INDICATION. R ENG NORMAL, ANTI-ICE ON. SMELL INCREASED. OXYGEN MASK -- BOTH PLTS ON. VIBRATION CEASED WITH THRUST LEVERS PULLED TO IDLE FOR DSCNT. 3 MINS LATER, LEVEL AT 13000 FT IN CLR. ANTI-ICE OFF, PWR UP, L ENG VIBRATION RETURNED (5.0). SMELL THROUGHOUT CABIN. NO SMOKE. RETARDED THRUST LEVERS TO IDLE. VIBRATION BOTH ENGS NORMAL, BUT L ENG NOISE. SMELL CLRED. CHKLISTS ACCOMPLISHED. IN DSCNT TO APCH AT IND RWY 23L, FLT ATTENDANT RPTED STREAMS OF FLAME OUT OF BACK OF L ENG. FLEW SINGLE ENG APCH WITH L ENG IN IDLE. UNEVENTFUL LNDG AT IND, EXCEPT 10000 LBS OVERWT. TAXIED TO GATE AFTER FIRE PERSONNEL CHKED ACFT/L ENG. EMER DECLARED DEPARTING 13000 FT. ALL ENG INDICATIONS ON BOTH ENGS NORMAL EXCEPT VIBRATION INDICATOR ON L ENG AT FL310 CRUISE AND WHEN PWR WAS ADVANCED AT 13000 FT.

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.