B737-400 crew lost dc bus #1 in ZSE class a.

Attributes
ACN	586572
Time
Date	200307
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : pdx.airport
State Reference	OR
Altitude	msl single value : 33000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zse.artcc
Operator	common carrier : air carrier
Make Model Name	B737-400
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
ASRS Report	586572
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : less severe other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : master caution light dc voltmeter dc ammeter other flight crewa other flight crewb
Resolutory Action	flight crew : landed in emergency condition flight crew : declared emergency none taken : anomaly accepted other
Consequence	other other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

FL330, south of pdx, lost dc bus #1. Troubleshot the situation, determined no power out of thrust reverser #1, and the 2-3 crossover had failed open. No power to the #1 dec bus. Further investigation revealed the dc #1 power circuit breaker opened. Continued to sfo, normal landing. After talking with maintenance and flight operations duty officer, emergency declared by dispatch. No other problems noted.

Original NASA ASRS Text

Title: B737-400 CREW LOST DC BUS #1 IN ZSE CLASS A.

Narrative: FL330, S OF PDX, LOST DC BUS #1. TROUBLESHOT THE SIT, DETERMINED NO PWR OUT OF THRUST REVERSER #1, AND THE 2-3 CROSSOVER HAD FAILED OPEN. NO PWR TO THE #1 DEC BUS. FURTHER INVESTIGATION REVEALED THE DC #1 PWR CIRCUIT BREAKER OPENED. CONTINUED TO SFO, NORMAL LNDG. AFTER TALKING WITH MAINT AND FLT OPS DUTY OFFICER, EMER DECLARED BY DISPATCH. NO OTHER PROBS NOTED.

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.