A B747-400 was dispatched in non compliance with the wrong #2 pneumatic valve deferred as inoperative per the MEL when in fact the inoperative high pressure regulator valve required a non icing clearance.

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Attributes
ACN	429375
Time
Date	199902
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B747-400
Operating Under FAR Part	Part 121
Flight Phase	ground : taxi ground : maintenance
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	other personnel other oversight : supervisor
Qualification	technician : airframe technician : powerplant technician : inspection authority
Experience	maintenance lead technician : 5 maintenance supervisor : 10 maintenance technician : 20
ASRS Report	429375
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : less severe maintenance problem : non compliance with mel non adherence : published procedure non adherence : far other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : #2 bleed overheat light other flight crewa other other : mech 1
Resolutory Action	other
Consequence	other
Factors
Maintenance	contributing factor : schedule pressure performance deficiency : non compliance with legal requirements
Supplementary
Problem Areas	Aircraft Maintenance Human Performance
Primary Problem	Maintenance Human Performance

Narrative:

After taxi out, crew reported via satcom radio that they had a #2 bleed overheat. I advised them to secure the bleed closed and proceed without restr. Later discovered that problem was with #2 prv which should have been deferred instead of the prsov which I did defer. Callback conversation with reporter revealed the following information: the reporter stated the reporter did not research the MEL adequately nor did he question the crew thoroughly. The reporter said he did not consider the non icing requirement.

Original NASA ASRS Text

Title: A B747-400 WAS DISPATCHED IN NON COMPLIANCE WITH THE WRONG #2 PNEUMATIC VALVE DEFERRED AS INOP PER THE MEL WHEN IN FACT THE INOP HIGH PRESSURE REGULATOR VALVE REQUIRED A NON ICING CLRNC.

Narrative: AFTER TAXI OUT, CREW RPTED VIA SATCOM RADIO THAT THEY HAD A #2 BLEED OVERHEAT. I ADVISED THEM TO SECURE THE BLEED CLOSED AND PROCEED WITHOUT RESTR. LATER DISCOVERED THAT PROB WAS WITH #2 PRV WHICH SHOULD HAVE BEEN DEFERRED INSTEAD OF THE PRSOV WHICH I DID DEFER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE RPTR DID NOT RESEARCH THE MEL ADEQUATELY NOR DID HE QUESTION THE CREW THOROUGHLY. THE RPTR SAID HE DID NOT CONSIDER THE NON ICING REQUIREMENT.

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.