Narrative:

During climb out after departing lax, part of the right wing (leading edge between the engine and the fuselage) was found to be torn/missing. A subsequent uneventful return to lax was made. Emergency equipment was standing by upon landing and dismissed by the captain after ascertaining the emergency equipment was not needed. I do not know what caused part of the right leading edge to break and I do not know when the breakage happened. Callback conversation with reporter revealed the following information: the reporter stated that nothing actually departed the aircraft. This information came from a passenger who related it to a flight attendant. The reporter said the #6 slat was visually checked extended and retracted and the area just behind the leading edge was separating. The reporter stated on landing the airplane had a slight vibration at flaps 1 degree and it was decided not to extend the slats fully. The reporter said the airplane was taken OTS and no information was available from maintenance. Supplemental information from acn 390147: at approximately 12000 ft MSL the senior flight attendant advised me that a passenger observed part of the right wing had separated from the aircraft. My first officer went back to the cabin and checked the right wing. He reported to me that aircraft skin was missing behind slat #6. My first officer contacted flight control and they agreed we should return to lax. I slowed the aircraft to 200 KTS and extended flaps to 1 degree. At that time we detected a small amount of vibration but no control problems. We landed on runway 25R at lax with no further problems.

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Original NASA ASRS Text

Title: A B757-200 ON INITIAL CLBOUT DECLARED AN EMER AND DIVERTED DUE TO THE R WING, #6 LEADING EDGE SLAT SEPARATING.

Narrative: DURING CLBOUT AFTER DEPARTING LAX, PART OF THE R WING (LEADING EDGE BTWN THE ENG AND THE FUSELAGE) WAS FOUND TO BE TORN/MISSING. A SUBSEQUENT UNEVENTFUL RETURN TO LAX WAS MADE. EMER EQUIP WAS STANDING BY UPON LNDG AND DISMISSED BY THE CAPT AFTER ASCERTAINING THE EMER EQUIP WAS NOT NEEDED. I DO NOT KNOW WHAT CAUSED PART OF THE R LEADING EDGE TO BREAK AND I DO NOT KNOW WHEN THE BREAKAGE HAPPENED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT NOTHING ACTUALLY DEPARTED THE ACFT. THIS INFO CAME FROM A PAX WHO RELATED IT TO A FLT ATTENDANT. THE RPTR SAID THE #6 SLAT WAS VISUALLY CHKED EXTENDED AND RETRACTED AND THE AREA JUST BEHIND THE LEADING EDGE WAS SEPARATING. THE RPTR STATED ON LNDG THE AIRPLANE HAD A SLIGHT VIBRATION AT FLAPS 1 DEG AND IT WAS DECIDED NOT TO EXTEND THE SLATS FULLY. THE RPTR SAID THE AIRPLANE WAS TAKEN OTS AND NO INFO WAS AVAILABLE FROM MAINT. SUPPLEMENTAL INFO FROM ACN 390147: AT APPROX 12000 FT MSL THE SENIOR FLT ATTENDANT ADVISED ME THAT A PAX OBSERVED PART OF THE R WING HAD SEPARATED FROM THE ACFT. MY FO WENT BACK TO THE CABIN AND CHKED THE R WING. HE RPTED TO ME THAT ACFT SKIN WAS MISSING BEHIND SLAT #6. MY FO CONTACTED FLT CTL AND THEY AGREED WE SHOULD RETURN TO LAX. I SLOWED THE ACFT TO 200 KTS AND EXTENDED FLAPS TO 1 DEG. AT THAT TIME WE DETECTED A SMALL AMOUNT OF VIBRATION BUT NO CTL PROBS. WE LANDED ON RWY 25R AT LAX WITH NO FURTHER PROBS.

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.