An md super 80 was operated in non compliance with an altitude alert circuit breaker not staying reset. Maintenance was not advised after first reset of the circuit breaker.

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Attributes
ACN	429492
Time
Date	199902
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : dsm.airport
State Reference	IA
Altitude	agl single value : 0
Environment
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	MD-80 Super 80
Operating Under FAR Part	Part 121
Flight Phase	ground : preflight ground : parked
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
ASRS Report	429492
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical non adherence : far non adherence : company policies non adherence : published procedure
Independent Detector	aircraft equipment other aircraft equipment : alt. alert window other flight crewa other flight crewb
Resolutory Action	aircraft : equipment problem dissipated flight crew : overcame equipment problem
Consequence	other
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

During preflight at dsm, we noticed the altitude alerting window was blank. Checking circuit breakers, we found #C-17 digital flight guidance system switch 'a' circuit breaker was popped. We were on APU power. The circuit breaker was reset. A min later, it popped again. We checked the MEL under altitude alert system and decided we were ok to go. After engine start, we decided to try another reset, in case it was power source related. During taxi out it popped again. We then noted that the amber yaw damper and mach trim lights were illuminated. Before returning to the gate we decided to give it 1 more try in case it was moisture, ice or temperature related. (Outside air temperature was 21 degrees F.) the circuit breaker remained set for the duration of the flight. We decided to document the occurrence as an entry to have the system checked out. After reviewing the MEL part 1 and operating manual, I realize we should have contacted maintenance technician and sought corrective action instead of resetting the circuit breaker after the first attempt.

Original NASA ASRS Text

Title: AN MD SUPER 80 WAS OPERATED IN NON COMPLIANCE WITH AN ALT ALERT CIRCUIT BREAKER NOT STAYING RESET. MAINT WAS NOT ADVISED AFTER FIRST RESET OF THE CIRCUIT BREAKER.

Narrative: DURING PREFLT AT DSM, WE NOTICED THE ALT ALERTING WINDOW WAS BLANK. CHKING CIRCUIT BREAKERS, WE FOUND #C-17 DIGITAL FLT GUIDANCE SYS SWITCH 'A' CIRCUIT BREAKER WAS POPPED. WE WERE ON APU PWR. THE CIRCUIT BREAKER WAS RESET. A MIN LATER, IT POPPED AGAIN. WE CHKED THE MEL UNDER ALT ALERT SYS AND DECIDED WE WERE OK TO GO. AFTER ENG START, WE DECIDED TO TRY ANOTHER RESET, IN CASE IT WAS PWR SOURCE RELATED. DURING TAXI OUT IT POPPED AGAIN. WE THEN NOTED THAT THE AMBER YAW DAMPER AND MACH TRIM LIGHTS WERE ILLUMINATED. BEFORE RETURNING TO THE GATE WE DECIDED TO GIVE IT 1 MORE TRY IN CASE IT WAS MOISTURE, ICE OR TEMP RELATED. (OUTSIDE AIR TEMP WAS 21 DEGS F.) THE CIRCUIT BREAKER REMAINED SET FOR THE DURATION OF THE FLT. WE DECIDED TO DOCUMENT THE OCCURRENCE AS AN ENTRY TO HAVE THE SYS CHKED OUT. AFTER REVIEWING THE MEL PART 1 AND OPERATING MANUAL, I REALIZE WE SHOULD HAVE CONTACTED MAINT TECHNICIAN AND SOUGHT CORRECTIVE ACTION INSTEAD OF RESETTING THE CIRCUIT BREAKER AFTER THE FIRST ATTEMPT.

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.