An L1011 was dispatched in non compliance with #1 idg deferred per the MEL in conflict with a previo...

Attributes
ACN	446491
Time
Date	199908
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : yyz.tower
Operator	common carrier : air carrier
Make Model Name	L-1011 Tri-Star All Series
Operating Under FAR Part	Part 121
Flight Phase	ground : preflight ground : parked ground : maintenance
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 80 flight time total : 15400 flight time type : 2800
ASRS Report	446491
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : multi engine pilot : instrument
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper documentation maintenance problem : non compliance with mel maintenance problem : improper maintenance non adherence : published procedure
Independent Detector	aircraft equipment other aircraft equipment : #1 generator control other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact
Consequence	other
Factors
Maintenance	contributing factor : manuals contributing factor : schedule pressure performance deficiency : non compliance with legal requirements performance deficiency : repair performance deficiency : testing performance deficiency : installation
Supplementary
Problem Areas	Maintenance Human Performance Chart Or Publication Aircraft Company
Primary Problem	Maintenance Human Performance
Situations
Publication	Minimum Equipment List

Narrative:

Preflight found aircraft had multiple deferrals (10). Went over each one with maintenance personnel present, having them replace missing deferral stickers. 2 deferrals were interrelated -- electrical system light on pilot's caution warning annunciator panel inoperative and #1 idg. The electrical system light required maintenance to perform a light test on flight engineer's electrical system panel, for the flight engineer to scan electrical panel during takeoff for abnormal indications, and cruise to scan electrical system panel more frequently. The MEL also stated 3 idg system are operative and referred to the idg system MEL. Upon reading idg MEL, it stated 3 were installed, 2 were required for dispatch and listed APU operating procedures below 10000 ft and selecting essential power to operating generators. Unfortunately, in going over the procedures to operate the aircraft with multiple MEL's, I missed the point with electrical system light inoperative on annunciator panel inoperative, 3 idg's were required -- not 2 idg's and an APU generator. Not only did I miss this, maintenance control who issued the mels, the dispatcher, the mechanic who signed the maintenance release, and the mechanics I discussed the MEL's missed it. During quiet time during cruise, discovered mistake. Notified maintenance and outbound crew of mistake. Maintenance repaired #1 idg.

Original NASA ASRS Text

Title: AN L1011 WAS DISPATCHED IN NON COMPLIANCE WITH #1 IDG DEFERRED PER THE MEL IN CONFLICT WITH A PREVIOUS DEFERRED ITEM.

Narrative: PREFLT FOUND ACFT HAD MULTIPLE DEFERRALS (10). WENT OVER EACH ONE WITH MAINT PERSONNEL PRESENT, HAVING THEM REPLACE MISSING DEFERRAL STICKERS. 2 DEFERRALS WERE INTERRELATED -- ELECTRICAL SYS LIGHT ON PLT'S CAUTION WARNING ANNUNCIATOR PANEL INOP AND #1 IDG. THE ELECTRICAL SYS LIGHT REQUIRED MAINT TO PERFORM A LIGHT TEST ON FE'S ELECTRICAL SYS PANEL, FOR THE FE TO SCAN ELECTRICAL PANEL DURING TKOF FOR ABNORMAL INDICATIONS, AND CRUISE TO SCAN ELECTRICAL SYS PANEL MORE FREQUENTLY. THE MEL ALSO STATED 3 IDG SYS ARE OPERATIVE AND REFERRED TO THE IDG SYS MEL. UPON READING IDG MEL, IT STATED 3 WERE INSTALLED, 2 WERE REQUIRED FOR DISPATCH AND LISTED APU OPERATING PROCS BELOW 10000 FT AND SELECTING ESSENTIAL PWR TO OPERATING GENERATORS. UNFORTUNATELY, IN GOING OVER THE PROCS TO OPERATE THE ACFT WITH MULTIPLE MEL'S, I MISSED THE POINT WITH ELECTRICAL SYS LIGHT INOP ON ANNUNCIATOR PANEL INOP, 3 IDG'S WERE REQUIRED -- NOT 2 IDG'S AND AN APU GENERATOR. NOT ONLY DID I MISS THIS, MAINT CTL WHO ISSUED THE MELS, THE DISPATCHER, THE MECH WHO SIGNED THE MAINT RELEASE, AND THE MECHS I DISCUSSED THE MEL'S MISSED IT. DURING QUIET TIME DURING CRUISE, DISCOVERED MISTAKE. NOTIFIED MAINT AND OUTBOUND CREW OF MISTAKE. MAINT REPAIRED #1 IDG.

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.

An L1011 was dispatched in non compliance with #1 idg deferred per the MEL in conflict with a previous deferred item.