|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||airport : mia|
|Altitude||agl bound lower : 0|
agl bound upper : 0
|Operator||common carrier : air carrier|
|Make Model Name||Widebody, Low Wing, 3 Turbojet Eng|
|Navigation In Use||Other|
|Flight Phase||ground : parked|
ground : preflight
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : atp|
|Function||other personnel other|
|Qualification||other other : other|
|Anomaly||aircraft equipment problem : critical|
non adherence : far
non adherence : published procedure
|Independent Detector||other flight crewa|
|Resolutory Action||none taken : unable|
|Air Traffic Incident||other|
C system brake accumulator would not hold a charge. If you pressurized the system and then turned pumps off, C system dropped to 0 pressure. As such, we had or would have no back up braking action if B system were to fail. The MEL book so states that you should get 8 brake applications with C system accumulator fully charged. We could only get 1 application before attaining a 0 reading on the gauge. All other widebody transport aircraft will hold a 3000 psi charge with no pumps on. This aircraft would not. Air carrier maintenance said this was the normal way the system operated and so stated in the sign off of the book.
Original NASA ASRS Text
Title: MINIMUM EQUIPMENT LIST INTERPRETED TO PERMIT OPERATION WITH A FLAT HYDRAULIC ACCUMULATOR.
Narrative: C SYS BRAKE ACCUMULATOR WOULD NOT HOLD A CHARGE. IF YOU PRESSURIZED THE SYS AND THEN TURNED PUMPS OFF, C SYS DROPPED TO 0 PRESSURE. AS SUCH, WE HAD OR WOULD HAVE NO BACK UP BRAKING ACTION IF B SYS WERE TO FAIL. THE MEL BOOK SO STATES THAT YOU SHOULD GET 8 BRAKE APPLICATIONS WITH C SYS ACCUMULATOR FULLY CHARGED. WE COULD ONLY GET 1 APPLICATION BEFORE ATTAINING A 0 READING ON THE GAUGE. ALL OTHER WDB ACFT WILL HOLD A 3000 PSI CHARGE WITH NO PUMPS ON. THIS ACFT WOULD NOT. ACR MAINT SAID THIS WAS THE NORMAL WAY THE SYS OPERATED AND SO STATED IN THE SIGN OFF OF THE BOOK.
Data retrieved from NASA's ASRS site as of August 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.