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A B737-400 flight crew noted they had no RNAV capability because of an MEL's fuel quant indicator and no VNAV capability on the FMC.
| Attributes | |
| ACN | 804662 |
| Time | |
| Date | 200809 |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | airport : zzz.airport |
| State Reference | US |
| Altitude | agl single value : 750 |
| Environment | |
| Light | Daylight |
| Aircraft 1 | |
| Operator | common carrier : air carrier |
| Make Model Name | B737-400 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | ground : taxi |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| ASRS Report | 804662 |
| Events | |
| Anomaly | aircraft equipment problem : less severe |
| Independent Detector | other flight crewa |
| Resolutory Action | none taken : anomaly accepted |
| Supplementary | |
| Problem Areas | Company Aircraft |
| Primary Problem | Company |
Narrative:
Flying 737-400 with several MEL's; including fuel quantity gauge inoperative. Dispatch requested and ATC assigned RNAV departure. Upon entering weight and balance information into CDU; we realized that predep could not be completed due to no fuel quantity and no VNAV capability on the FMC. No runway update prompt could be generated. Because aircraft capability for RNAV departure degraded to; at the very least; below that of the 737-300; I refused RNAV departure and requested the appropriate SID. After a 30-60 second delay and changing FMC route; tower reclred and we departed. I informed dispatcher; senior check airman; and the oncoming crew of the RNAV degradation of the aircraft; and then submitted this report. Dispatch believed aircraft capable of RNAV departure because there is either no applicable MEL degrading the aircraft; or if there is an applicable MEL; both dispatch and avionics maintenance is unaware of it. Update bulletin to reflect this additional disability of the 737-400 to perform RNAV departures when the FMC is unable to generate a runway update prompt. Update the MEL to reflect the aforementioned and ensure that dispatch and maintenance are informed.
Original NASA ASRS Text
Title: A B737-400 FLT CREW NOTED THEY HAD NO RNAV CAPABILITY BECAUSE OF AN MEL'S FUEL QUANT INDICATOR AND NO VNAV CAPABILITY ON THE FMC.
Narrative: FLYING 737-400 WITH SEVERAL MEL'S; INCLUDING FUEL QUANTITY GAUGE INOP. DISPATCH REQUESTED AND ATC ASSIGNED RNAV DEP. UPON ENTERING WT AND BAL INFO INTO CDU; WE REALIZED THAT PREDEP COULD NOT BE COMPLETED DUE TO NO FUEL QUANTITY AND NO VNAV CAPABILITY ON THE FMC. NO RWY UPDATE PROMPT COULD BE GENERATED. BECAUSE ACFT CAPABILITY FOR RNAV DEP DEGRADED TO; AT THE VERY LEAST; BELOW THAT OF THE 737-300; I REFUSED RNAV DEP AND REQUESTED THE APPROPRIATE SID. AFTER A 30-60 SECOND DELAY AND CHANGING FMC RTE; TWR RECLRED AND WE DEPARTED. I INFORMED DISPATCHER; SENIOR CHK AIRMAN; AND THE ONCOMING CREW OF THE RNAV DEGRADATION OF THE ACFT; AND THEN SUBMITTED THIS RPT. DISPATCH BELIEVED ACFT CAPABLE OF RNAV DEP BECAUSE THERE IS EITHER NO APPLICABLE MEL DEGRADING THE ACFT; OR IF THERE IS AN APPLICABLE MEL; BOTH DISPATCH AND AVIONICS MAINT IS UNAWARE OF IT. UPDATE BULLETIN TO REFLECT THIS ADDITIONAL DISABILITY OF THE 737-400 TO PERFORM RNAV DEPS WHEN THE FMC IS UNABLE TO GENERATE A RWY UPDATE PROMPT. UPDATE THE MEL TO REFLECT THE AFOREMENTIONED AND ENSURE THAT DISPATCH AND MAINT ARE INFORMED.
Data retrieved from NASA's ASRS site as of May 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.