Flight crew of B757 are dispatched with out of date FMC database. Discover on trans gulf of mexico leg. MEL for dispatch which requires confirmation of waypoint latitude-longitude. Reporter discovered latitude-longitude coordinates are not shown on the 'Q' rtes across the gulf. Thus; the dispatch was not legal.

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Attributes
ACN	657866
Time
Date	200505
Local Time Of Day	1201 To 1800
Place
Locale Reference	intersection : redfn
State Reference	FO
Altitude	msl single value : 36000
Aircraft 1
Controlling Facilities	artcc : zhu.artcc
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	657866
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	657864
Events
Anomaly	aircraft equipment problem : critical non adherence : published procedure non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : fmc initialization page other flight crewa other flight crewb
Resolutory Action	none taken : anomaly accepted other
Consequence	other
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft Chart Or Publication Company FAA
Primary Problem	Chart Or Publication

Narrative:

Twice I have flown gulf of mexico 'Q' rtes in an aircraft with the FMC navigation database out of date (B757 MEL 34-21C). For flight XXX I even contacted dispatch about validity of FMC with out-of-date database. I was assured there were no problems. However; after additional review of MEL 34-21C and its requirement to use flight manual ii charts to enter data into the FMS; the only fixes that can be entered into the FMS for navigation are those with latitude/longitude printed on the flight manual ii charts. Those fixes can be entered either by latitude/longitude from the flight manual ii chart or by identify (only after verifying latitude/longitude on the FMC 'navigation data' page matches the latitude/longitude from the flight manual ii chart). I conclude MEL 34-21C does not allow RNAV rtes (like the 'Q' rtes) to be flown in an aircraft with an out-of-date navigation database (many other fixes also lack latitude/longitude on flight manual ii charts).

Original NASA ASRS Text

Title: FLT CREW OF B757 ARE DISPATCHED WITH OUT OF DATE FMC DATABASE. DISCOVER ON TRANS GULF OF MEXICO LEG. MEL FOR DISPATCH WHICH REQUIRES CONFIRMATION OF WAYPOINT LATITUDE-LONGITUDE. RPTR DISCOVERED LATITUDE-LONGITUDE COORDINATES ARE NOT SHOWN ON THE 'Q' RTES ACROSS THE GULF. THUS; THE DISPATCH WAS NOT LEGAL.

Narrative: TWICE I HAVE FLOWN GULF OF MEXICO 'Q' RTES IN AN ACFT WITH THE FMC NAV DATABASE OUT OF DATE (B757 MEL 34-21C). FOR FLT XXX I EVEN CONTACTED DISPATCH ABOUT VALIDITY OF FMC WITH OUT-OF-DATE DATABASE. I WAS ASSURED THERE WERE NO PROBS. HOWEVER; AFTER ADDITIONAL REVIEW OF MEL 34-21C AND ITS REQUIREMENT TO USE FLT MANUAL II CHARTS TO ENTER DATA INTO THE FMS; THE ONLY FIXES THAT CAN BE ENTERED INTO THE FMS FOR NAV ARE THOSE WITH LATITUDE/LONGITUDE PRINTED ON THE FLT MANUAL II CHARTS. THOSE FIXES CAN BE ENTERED EITHER BY LATITUDE/LONGITUDE FROM THE FLT MANUAL II CHART OR BY IDENT (ONLY AFTER VERIFYING LATITUDE/LONGITUDE ON THE FMC 'NAV DATA' PAGE MATCHES THE LATITUDE/LONGITUDE FROM THE FLT MANUAL II CHART). I CONCLUDE MEL 34-21C DOES NOT ALLOW RNAV RTES (LIKE THE 'Q' RTES) TO BE FLOWN IN AN ACFT WITH AN OUT-OF-DATE NAV DATABASE (MANY OTHER FIXES ALSO LACK LATITUDE/LONGITUDE ON FLT MANUAL II CHARTS).

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.