A B757-200 flight crew on descent experienced EICAS message forward equipment smoke following diffic...

Attributes
ACN	811588
Time
Date	200811
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 7000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : zzz.tracon tower : den.tower
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 205 flight time total : 12750 flight time type : 8215
ASRS Report	811588
Events
Anomaly	aircraft equipment problem : critical other anomaly
Independent Detector	aircraft equipment other aircraft equipment : eicas
Resolutory Action	flight crew : declared emergency flight crew : landed in emergency condition
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

While descending on the arrival at an ATC assigned 310 KTS/12000 ft; the first officer and I both noted a 'surging' sound and discovered that the left recirculation fan was cycling on and off; with the 'inoperative' light coming on and off. We also got a status message; 'ovbd exterior valve open.' complied with the QRH for left recirculation fan. Descending to 7000 ft on downwind just to the north of the runways; got a 'forward equipment smoke' EICAS message and the 'smoke' discrete light on the overhead panel. Declared an emergency with ATC and complied with the QRH. First officer quickly briefed flight attendants. Vectored expeditiously to final for runway xxl; landed and cleared the runway. Stopped on the taxiway for quick inspection by the fire crew. A PA to passenger was made. Proceeded to gate. At no time was there any indication of smoke in the cockpit or cabin. Mechanics that met aircraft at gate also reported no evidence or smell of smoke in equipment bays. Flight attendants reported no undue concern by any passenger.

Original NASA ASRS Text

Title: A B757-200 FLIGHT CREW ON DESCENT EXPERIENCED EICAS MESSAGE FORWARD EQUIP SMOKE FOLLOWING DIFFICULTY WITH ONE OF THE RECIRCULATING FANS. THEY DECLARED AN EMERGENCY; RAN THE QRH; AND LANDED WITHOUT INCIDENT.

Narrative: WHILE DSNDING ON THE ARR AT AN ATC ASSIGNED 310 KTS/12000 FT; THE FO AND I BOTH NOTED A 'SURGING' SOUND AND DISCOVERED THAT THE L RECIRCULATION FAN WAS CYCLING ON AND OFF; WITH THE 'INOP' LIGHT COMING ON AND OFF. WE ALSO GOT A STATUS MESSAGE; 'OVBD EXTERIOR VALVE OPEN.' COMPLIED WITH THE QRH FOR L RECIRCULATION FAN. DSNDING TO 7000 FT ON DOWNWIND JUST TO THE N OF THE RWYS; GOT A 'FORWARD EQUIP SMOKE' EICAS MESSAGE AND THE 'SMOKE' DISCRETE LIGHT ON THE OVERHEAD PANEL. DECLARED AN EMER WITH ATC AND COMPLIED WITH THE QRH. FO QUICKLY BRIEFED FLT ATTENDANTS. VECTORED EXPEDITIOUSLY TO FINAL FOR RWY XXL; LANDED AND CLRED THE RWY. STOPPED ON THE TXWY FOR QUICK INSPECTION BY THE FIRE CREW. A PA TO PAX WAS MADE. PROCEEDED TO GATE. AT NO TIME WAS THERE ANY INDICATION OF SMOKE IN THE COCKPIT OR CABIN. MECHS THAT MET ACFT AT GATE ALSO RPTED NO EVIDENCE OR SMELL OF SMOKE IN EQUIP BAYS. FLT ATTENDANTS RPTED NO UNDUE CONCERN BY ANY PAX.

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.

A B757-200 flight crew on descent experienced EICAS message forward equipment smoke following difficulty with one of the recirculating fans. They declared an emergency; ran the QRH; and landed without incident.