B-767-200 is grounded for a leading edge slat EICAS asymmetry indication.

Attributes
ACN	303799
Time
Date	199504
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : clt
State Reference	NC
Altitude	agl bound lower : 0 agl bound upper : 0
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B767-200
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
ASRS Report	303799
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	other other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Boeing 767 returned to field with EICAS message 'leading edge slat asymmetry.' a visual inspection was made of leading edge devices from ground. Slats were raised electrically to fully retracted position and EICAS message was erased as per boeing fim manual along with associated bits performed on pseu computer. Flight control computer and fseu computer bits were also accomplished per instructions. No hard fault existed, no latched messaged existed and leading edge slats were operated numerous times electrically and hydraulically with no recurrence of EICAS message. Operation was observed from ground also with no defective operation noted. Aircraft was released from maintenance and dispatched for flight. After takeoff, EICAS message returned and aircraft returned to field again. Aircraft at this time was grounded and taken OTS for additional maintenance and trouble- shooting and I was no longer involved in the corrective repairs. It was later found that, with the nature of the problem, the message would only appear with a flight load on the leading edge slats.

Original NASA ASRS Text

Title: B-767-200 IS GNDED FOR A LEADING EDGE SLAT EICAS ASYMMETRY INDICATION.

Narrative: BOEING 767 RETURNED TO FIELD WITH EICAS MESSAGE 'LEADING EDGE SLAT ASYMMETRY.' A VISUAL INSPECTION WAS MADE OF LEADING EDGE DEVICES FROM GND. SLATS WERE RAISED ELECTRICALLY TO FULLY RETRACTED POS AND EICAS MESSAGE WAS ERASED AS PER BOEING FIM MANUAL ALONG WITH ASSOCIATED BITS PERFORMED ON PSEU COMPUTER. FLT CTL COMPUTER AND FSEU COMPUTER BITS WERE ALSO ACCOMPLISHED PER INSTRUCTIONS. NO HARD FAULT EXISTED, NO LATCHED MESSAGED EXISTED AND LEADING EDGE SLATS WERE OPERATED NUMEROUS TIMES ELECTRICALLY AND HYDRAULICALLY WITH NO RECURRENCE OF EICAS MESSAGE. OP WAS OBSERVED FROM GND ALSO WITH NO DEFECTIVE OP NOTED. ACFT WAS RELEASED FROM MAINT AND DISPATCHED FOR FLT. AFTER TKOF, EICAS MESSAGE RETURNED AND ACFT RETURNED TO FIELD AGAIN. ACFT AT THIS TIME WAS GNDED AND TAKEN OTS FOR ADDITIONAL MAINT AND TROUBLE- SHOOTING AND I WAS NO LONGER INVOLVED IN THE CORRECTIVE REPAIRS. IT WAS LATER FOUND THAT, WITH THE NATURE OF THE PROB, THE MESSAGE WOULD ONLY APPEAR WITH A FLT LOAD ON THE LEADING EDGE SLATS.

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.