A B737-700 was dispatched with the #1 engine nose cowl anti-ice valve open per MEL special procedures. Tech failed to lock high stage valve closed; rendering the pressure regulator and shutoff valve closed.

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Attributes
ACN	671956
Time
Date	200509
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll ground : maintenance
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	maintenance : technician
ASRS Report	671956
Person 2
Affiliation	company : air carrier
Function	maintenance : lead technician
ASRS Report	671957
Events
Anomaly	aircraft equipment problem : critical maintenance problem : non compliance with mel maintenance problem : improper maintenance maintenance problem : improper documentation non adherence : published procedure non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : l eng bleed warning other flight crewa
Resolutory Action	none taken : detected after the fact
Factors
Maintenance	contributing factor : schedule pressure contributing factor : manuals performance deficiency : non compliance with legal requirements
Supplementary
Problem Areas	Weather Chart Or Publication Aircraft Maintenance Human Performance
Primary Problem	Maintenance Human Performance
Situations
Publication	MEL

Narrative:

Plane came in with #1 cowl anti-ice valve inoperative. It was decided to place it on MEL. The #1 high stage valve should have been locked closed as the cowl anti-ice valve was locked open. After he was airborne; he called us to tell us the left duct pressure was zero. At this point I realized I locked out the pr/sov instead of the high stage valve. Factors involved were being rushed; under pressure (self imposed). I failed to confirm I was working on the right valve.

Original NASA ASRS Text

Title: A B737-700 WAS DISPATCHED WITH THE #1 ENG NOSE COWL ANTI-ICE VALVE OPEN PER MEL SPECIAL PROCS. TECH FAILED TO LOCK HIGH STAGE VALVE CLOSED; RENDERING THE PRESSURE REGULATOR AND SHUTOFF VALVE CLOSED.

Narrative: PLANE CAME IN WITH #1 COWL ANTI-ICE VALVE INOP. IT WAS DECIDED TO PLACE IT ON MEL. THE #1 HIGH STAGE VALVE SHOULD HAVE BEEN LOCKED CLOSED AS THE COWL ANTI-ICE VALVE WAS LOCKED OPEN. AFTER HE WAS AIRBORNE; HE CALLED US TO TELL US THE L DUCT PRESSURE WAS ZERO. AT THIS POINT I REALIZED I LOCKED OUT THE PR/SOV INSTEAD OF THE HIGH STAGE VALVE. FACTORS INVOLVED WERE BEING RUSHED; UNDER PRESSURE (SELF IMPOSED). I FAILED TO CONFIRM I WAS WORKING ON THE RIGHT VALVE.

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.