A B737-300 was dispatched with #4 leading edge slat position indication system deferred inoperative ...

Attributes
ACN	353587
Time
Date	199611
Day	Thu
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : fsd
State Reference	SD
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	ground : preflight other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
ASRS Report	353587
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical non adherence : far non adherence : published procedure other anomaly other
Independent Detector	other flight crewa other other : unspecified cockpit
Resolutory Action	none taken : anomaly accepted other
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

During taxi out the flight crew experienced an indication problem with the #4 leading edge slat, deferable per the MEL with checks accomplished to assure proper operation. Part of the MEL check is to confirm 'B' system hydraulic press and test both stall warning system. This airplane had another deferred item on the 'B' system hydraulic pressurize indicator reported as inoperative. The placard for this item stated in part that 'B' system pressure was to be verified by using the hydraulic brake pressure indicator which was functioning normally. All checks were accomplished and the airplane departed after I had confirmed with another controller if this alternate means of verification was safe. I could see no reason why it was not safe as the placard specifically stated to use this indicator for verification of system pressure. My main concern in filing this report is under the human factors portion, it was XX00 and nearing the end of duty shift, I was tired and unsure causing me to become confused when reading the information. The flight crew was in a hurry and did take some prompting to slow down so we could assure a safe dispatch. I plan to discuss the wording of the MEL with operational engineering group to clarify an acceptable means is inserted.

Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED WITH #4 LEADING EDGE SLAT POS INDICATION SYS DEFERRED INOP WITH A PREVIOUS DEFERRED ITEM ON 'B' HYD SYS PRESSURE INDICATION INOP. THIS WAS IN CONFLICT WITH THE MEL.

Narrative: DURING TAXI OUT THE FLC EXPERIENCED AN INDICATION PROB WITH THE #4 LEADING EDGE SLAT, DEFERABLE PER THE MEL WITH CHKS ACCOMPLISHED TO ASSURE PROPER OP. PART OF THE MEL CHK IS TO CONFIRM 'B' SYS HYD PRESS AND TEST BOTH STALL WARNING SYS. THIS AIRPLANE HAD ANOTHER DEFERRED ITEM ON THE 'B' SYS HYD PRESSURIZE INDICATOR RPTED AS INOP. THE PLACARD FOR THIS ITEM STATED IN PART THAT 'B' SYS PRESSURE WAS TO BE VERIFIED BY USING THE HYD BRAKE PRESSURE INDICATOR WHICH WAS FUNCTIONING NORMALLY. ALL CHKS WERE ACCOMPLISHED AND THE AIRPLANE DEPARTED AFTER I HAD CONFIRMED WITH ANOTHER CTLR IF THIS ALTERNATE MEANS OF VERIFICATION WAS SAFE. I COULD SEE NO REASON WHY IT WAS NOT SAFE AS THE PLACARD SPECIFICALLY STATED TO USE THIS INDICATOR FOR VERIFICATION OF SYS PRESSURE. MY MAIN CONCERN IN FILING THIS RPT IS UNDER THE HUMAN FACTORS PORTION, IT WAS XX00 AND NEARING THE END OF DUTY SHIFT, I WAS TIRED AND UNSURE CAUSING ME TO BECOME CONFUSED WHEN READING THE INFO. THE FLC WAS IN A HURRY AND DID TAKE SOME PROMPTING TO SLOW DOWN SO WE COULD ASSURE A SAFE DISPATCH. I PLAN TO DISCUSS THE WORDING OF THE MEL WITH OPERATIONAL ENGINEERING GROUP TO CLARIFY AN ACCEPTABLE MEANS IS INSERTED.

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.

A B737-300 was dispatched with #4 leading edge slat position indication system deferred inoperative with a previous deferred item on 'B' hydraulic system pressure indication inoperative. This was in conflict with the MEL.