Distracted by malfunctioning fuel valve indication; flight crew of B737-700 descends prematurely.

Attributes
ACN	804445
Time
Date	200809
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : atl.airport
State Reference	GA
Altitude	msl single value : 7000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : a80.tracon
Operator	common carrier : air carrier
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	804445
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude
Independent Detector	aircraft equipment other aircraft equipment : spar valve closed light
Resolutory Action	controller : issued new clearance controller : issued advisory flight crew : returned to assigned altitude
Supplementary
Problem Areas	ATC Human Performance Aircraft Flight Crew Human Performance
Primary Problem	Ambiguous

Narrative:

On downwind descending through 7000 ft; the left engine; #1 'spar valve closed' light illuminated full bright. The light; when illuminated full bright indicates that the fuel valve disagrees with the commanded position. The valve is commanded open when the engine is running normally allowing fuel to flow. When it is bright and the engine fuel selector is on; it indicates the valve is commanded open; but actually in a closed position; thus not allowing fuel to the engine. As we were preparing to ask for priority; atl approach turned us on to a base leg with a turn to final shortly after. I heard; as my first officer did and read back; 'turn to heading 240 degrees; descend to 4000 ft; cleared for the visual approach to runway 26R.' upon reaching 4000 ft; the approach controller said we were only cleared down to 5000 ft and we should climb back to 5000 ft; which we did. Prior to reaching 5000 ft the tlr said to 'just stay on the GS from there.' our approximately altitude was about 4800 ft. There was no TCAS alert.

Original NASA ASRS Text

Title: DISTRACTED BY MALFUNCTIONING FUEL VALVE INDICATION; FLT CREW OF B737-700 DESCENDS PREMATURELY.

Narrative: ON DOWNWIND DSNDING THROUGH 7000 FT; THE L ENG; #1 'SPAR VALVE CLOSED' LIGHT ILLUMINATED FULL BRIGHT. THE LIGHT; WHEN ILLUMINATED FULL BRIGHT INDICATES THAT THE FUEL VALVE DISAGREES WITH THE COMMANDED POS. THE VALVE IS COMMANDED OPEN WHEN THE ENG IS RUNNING NORMALLY ALLOWING FUEL TO FLOW. WHEN IT IS BRIGHT AND THE ENG FUEL SELECTOR IS ON; IT INDICATES THE VALVE IS COMMANDED OPEN; BUT ACTUALLY IN A CLOSED POS; THUS NOT ALLOWING FUEL TO THE ENG. AS WE WERE PREPARING TO ASK FOR PRIORITY; ATL APCH TURNED US ON TO A BASE LEG WITH A TURN TO FINAL SHORTLY AFTER. I HEARD; AS MY FO DID AND READ BACK; 'TURN TO HDG 240 DEGS; DSND TO 4000 FT; CLRED FOR THE VISUAL APCH TO RWY 26R.' UPON REACHING 4000 FT; THE APCH CTLR SAID WE WERE ONLY CLRED DOWN TO 5000 FT AND WE SHOULD CLB BACK TO 5000 FT; WHICH WE DID. PRIOR TO REACHING 5000 FT THE TLR SAID TO 'JUST STAY ON THE GS FROM THERE.' OUR APPROX ALT WAS ABOUT 4800 FT. THERE WAS NO TCAS ALERT.

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.