Minimum equipment list interpreted to permit operation with a flat hydraulic accumulator.

Attributes
ACN	84518
Time
Date	198803
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mia
State Reference	FL
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 3 Turbojet Eng
Navigation In Use	Other
Flight Phase	ground : parked ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	84518
Person 2
Function	other personnel other
Qualification	other other : other
Events
Anomaly	aircraft equipment problem : critical non adherence : far non adherence : published procedure
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

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.