During preflight logbook review; a B757-200 captain notices that center hydraulic system #2 electric...

Attributes
ACN	803030
Time
Date	200809
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	803030
Events
Anomaly	aircraft equipment problem : less severe maintenance problem : improper maintenance maintenance problem : improper documentation maintenance problem : non compliance with mel non adherence : published procedure non adherence : far
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact other
Consequence	other
Factors
Maintenance	contributing factor : briefing performance deficiency : non compliance with legal requirements performance deficiency : testing performance deficiency : logbook entry performance deficiency : inspection performance deficiency : fault isolation
Supplementary
Problem Areas	Flight Crew Human Performance Maintenance Human Performance Aircraft Company
Primary Problem	Maintenance Human Performance

Narrative:

During preflight; I noticed that the flight plan note and logbook entry # described a center hydraulic pump #2 press indicator light problem and was coded 29-4C; but the initial information sheet and the placard was coded 29-2; which is a hydraulic pump failure. When I checked the pump operation; the #2 pump breaker was not collared per 29-2 and system pressure was normal; but the center pump #1 low pressure indicator and the center system low pressure indicator appeared to be wired backwards. I notified ZZZ maintenance and maintenance control; and the ZZZ mechanics found the wiring problem and quickly fixed it. This aircraft had been flying like this for 15 days.callback conversation with reporter revealed the following information: reporter stated he believed the issue was originally written-up as a pressure indication problem of the center hydraulic system pressure light indicator. Somehow their maintenance control ended up deferring the center hydraulic system #2 electric motor pump (acmp) as having failed. Reporter stated when he put the center hydraulic system # 2 electric pump on; he noticed the #2 pump pressure light would go out (as it should) and so would the center hydraulic #1 electric pump pressure indicator; even though the #1 pump was not actually 'on.' but the center hydraulic system pressure light was still 'on.' the center hydraulic system pressure light will go out if either #1 or #2 electric pumps are switched on. Reporter stated; that after explaining this to the mechanics; he believes they switched the #1 pump low pressure sensor indicator connector with the center hydraulic system pressure sensor indicator connector. All center hydraulic system lights and pressure indications functioned normally afterwards.

Original NASA ASRS Text

Title: DURING PREFLIGHT LOGBOOK REVIEW; A B757-200 CAPTAIN NOTICES THAT CENTER HYD SYSTEM #2 ELECTRICAL HYD PUMP WAS INCORRECTLY DEFERRED AS FAILED. #1 PUMP CONNECTOR SWITCHED WITH CENTER SYSTEM PRESSURE SENSOR.

Narrative: DURING PREFLT; I NOTICED THAT THE FLT PLAN NOTE AND LOGBOOK ENTRY # DESCRIBED A CTR HYD PUMP #2 PRESS INDICATOR LIGHT PROB AND WAS CODED 29-4C; BUT THE INITIAL INFO SHEET AND THE PLACARD WAS CODED 29-2; WHICH IS A HYD PUMP FAILURE. WHEN I CHECKED THE PUMP OPERATION; THE #2 PUMP BREAKER WAS NOT COLLARED PER 29-2 AND SYSTEM PRESSURE WAS NORMAL; BUT THE CTR PUMP #1 LOW PRESSURE INDICATOR AND THE CTR SYSTEM LOW PRESSURE INDICATOR APPEARED TO BE WIRED BACKWARDS. I NOTIFIED ZZZ MAINT AND MAINT CTL; AND THE ZZZ MECHANICS FOUND THE WIRING PROBLEM AND QUICKLY FIXED IT. THIS ACFT HAD BEEN FLYING LIKE THIS FOR 15 DAYS.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED HE BELIEVED THE ISSUE WAS ORIGINALLY WRITTEN-UP AS A PRESSURE INDICATION PROBLEM OF THE CENTER HYD SYSTEM PRESSURE LIGHT INDICATOR. SOMEHOW THEIR MAINT CONTROL ENDED UP DEFERRING THE CENTER HYD SYS #2 ELECTRIC MOTOR PUMP (ACMP) AS HAVING FAILED. REPORTER STATED WHEN HE PUT THE CENTER HYD SYS # 2 ELECTRIC PUMP ON; HE NOTICED THE #2 PUMP PRESSURE LIGHT WOULD GO OUT (AS IT SHOULD) AND SO WOULD THE CENTER HYD #1 ELECTRIC PUMP PRESSURE INDICATOR; EVEN THOUGH THE #1 PUMP WAS NOT ACTUALLY 'ON.' BUT THE CENTER HYD SYSTEM PRESSURE LIGHT WAS STILL 'ON.' THE CENTER HYD SYSTEM PRESSURE LIGHT WILL GO OUT IF EITHER #1 OR #2 ELECTRIC PUMPS ARE SWITCHED ON. REPORTER STATED; THAT AFTER EXPLAINING THIS TO THE MECHANICS; HE BELIEVES THEY SWITCHED THE #1 PUMP LOW PRESSURE SENSOR INDICATOR CONNECTOR WITH THE CENTER HYD SYSTEM PRESSURE SENSOR INDICATOR CONNECTOR. ALL CENTER HYD SYSTEM LIGHTS AND PRESSURE INDICATIONS FUNCTIONED NORMALLY AFTERWARDS.

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.

During preflight logbook review; a B757-200 captain notices that center hydraulic system #2 electrical hydraulic pump was incorrectly deferred as failed. #1 pump connector switched with center system pressure sensor.