Improper gear safe and or unsafe lights alert B737-300 flight crew to a tripped circuit breaker.

Attributes
ACN	715199
Time
Date	200610
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 7000
Environment
Flight Conditions	Marginal
Light	Night
Aircraft 1
Controlling Facilities	tracon : sct.tracon tower : anc.tower
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 202 flight time total : 9501 flight time type : 3263
ASRS Report	715199
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	aircraft equipment other aircraft equipment : lndg gear safe lights other flight crewa other flight crewb
Resolutory Action	flight crew : overcame equipment problem
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

On descent it was noted that only the red nose gear light illuminated when the throttles were retarded to idle (red left gear and right gear lights did not illuminate). An mrm write-up was sent reflecting this problem. Socal requested that the speed be reduced to 160 KIAS after the aircraft had passed smo VOR and was on a 065 degree heading. The gear handle was lowered and flaps extended to 15 degrees. The gear sounded as though they had extended normally but no green landing gear down lights illuminated. There was no landing gear warning horn sounding at this time. The landing gear unsafe indication checklist (14.70.8) was referenced. The landing gear air/ground relay and lights circuit breaker (P6-3) C18 was found tripped and was reset in accordance with the checklist. The landing gear lights then indicated '3 green.' a normal landing and taxi to the gate were accomplished. Lax maintenance was informed of the problem on taxi in.

Original NASA ASRS Text

Title: IMPROPER GEAR SAFE AND OR UNSAFE LIGHTS ALERT B737-300 FLT CREW TO A TRIPPED CIRCUIT BREAKER.

Narrative: ON DSCNT IT WAS NOTED THAT ONLY THE RED NOSE GEAR LIGHT ILLUMINATED WHEN THE THROTTLES WERE RETARDED TO IDLE (RED L GEAR AND R GEAR LIGHTS DID NOT ILLUMINATE). AN MRM WRITE-UP WAS SENT REFLECTING THIS PROB. SOCAL REQUESTED THAT THE SPD BE REDUCED TO 160 KIAS AFTER THE ACFT HAD PASSED SMO VOR AND WAS ON A 065 DEG HDG. THE GEAR HANDLE WAS LOWERED AND FLAPS EXTENDED TO 15 DEGS. THE GEAR SOUNDED AS THOUGH THEY HAD EXTENDED NORMALLY BUT NO GREEN LNDG GEAR DOWN LIGHTS ILLUMINATED. THERE WAS NO LNDG GEAR WARNING HORN SOUNDING AT THIS TIME. THE LNDG GEAR UNSAFE INDICATION CHKLIST (14.70.8) WAS REFED. THE LNDG GEAR AIR/GND RELAY AND LIGHTS CIRCUIT BREAKER (P6-3) C18 WAS FOUND TRIPPED AND WAS RESET IN ACCORDANCE WITH THE CHKLIST. THE LNDG GEAR LIGHTS THEN INDICATED '3 GREEN.' A NORMAL LNDG AND TAXI TO THE GATE WERE ACCOMPLISHED. LAX MAINT WAS INFORMED OF THE PROB ON TAXI IN.

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.