Reports of incorrect FMC performance software installation on B737 aircraft.

Attributes
ACN	434529
Time
Date	199904
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : phx.airport
State Reference	AZ
Aircraft 1
Controlling Facilities	tracon : p50.tracon
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : cfi pilot : commercial pilot : instrument pilot : multi engine pilot : atp
Experience	flight time last 90 days : 230 flight time total : 6980 flight time type : 2895
ASRS Report	434529
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical non adherence : company policies other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : fmc other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	other
Factors
Maintenance	contributing factor : engineering procedure performance deficiency : installation
Supplementary
Problem Areas	Flight Crew Human Performance Company Aircraft Maintenance Human Performance
Primary Problem	Company

Narrative:

During preflight, the FMC provided what appeared to be erroneous performance data for takeoff. The erroneous data was noticed and as a result all performance data, including 'dash' power settings for takeoff, were computed and used off of the hand-held on board performance computer. Safety was not compromised even though the aircraft FMC was not providing good performance data.

Original NASA ASRS Text

Title: RPTS OF INCORRECT FMC PERFORMANCE SOFTWARE INSTALLATION ON B737 ACFT.

Narrative: DURING PREFLT, THE FMC PROVIDED WHAT APPEARED TO BE ERRONEOUS PERFORMANCE DATA FOR TKOF. THE ERRONEOUS DATA WAS NOTICED AND AS A RESULT ALL PERFORMANCE DATA, INCLUDING 'DASH' PWR SETTINGS FOR TKOF, WERE COMPUTED AND USED OFF OF THE HAND-HELD ON BOARD PERFORMANCE COMPUTER. SAFETY WAS NOT COMPROMISED EVEN THOUGH THE ACFT FMC WAS NOT PROVIDING GOOD PERFORMANCE DATA.

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.