Narrative:

Regarding request for wake turbulence encounter reports. On civet profile descent to lax, 8 NM in trail of B727, at or just above 25L GS, with autoplt on, our MD80 rolled 15 degrees right in 5 seconds, then rolled left, past vertical, to about 15 degrees left, within 5-6 seconds, at which point the autoplt disengaged. No further disturbance, rest of approach and landing was normal. No observed traffic except for aircraft ahead, which was not in sight due to city lights. Callback conversation with reporter revealed the following information: the reporter was prompted to submit this report partly because the benign routine approach encountered the unusual wake. The wake encounter was so unexpected. The MD82 autoplt self disconnect almost never happens. The B727 was 8 mi ahead and appeared to be below even though it probably was following the GS and was at the same altitude at the same points along the ILS. This was a normal routine approach. All of a sudden the airplane rolled abruptly 15 degrees 1 way followed by a rapid roll in the other direction, banked to 15 degrees the other direction. The autoplt disconnected itself on this second roll.

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Original NASA ASRS Text

Title: DURING NORMAL ILS APCH, NO DIFFERENT THAN THOUSANDS OF PREVIOUS ILS APCHS IN SPACING AND SEPARATION, THE RPTR ENCOUNTERS SURPRISING WAKE TURB.

Narrative: REGARDING REQUEST FOR WAKE TURB ENCOUNTER RPTS. ON CIVET PROFILE DSCNT TO LAX, 8 NM IN TRAIL OF B727, AT OR JUST ABOVE 25L GS, WITH AUTOPLT ON, OUR MD80 ROLLED 15 DEGS R IN 5 SECONDS, THEN ROLLED L, PAST VERT, TO ABOUT 15 DEGS L, WITHIN 5-6 SECONDS, AT WHICH POINT THE AUTOPLT DISENGAGED. NO FURTHER DISTURBANCE, REST OF APCH AND LNDG WAS NORMAL. NO OBSERVED TFC EXCEPT FOR ACFT AHEAD, WHICH WAS NOT IN SIGHT DUE TO CITY LIGHTS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR WAS PROMPTED TO SUBMIT THIS RPT PARTLY BECAUSE THE BENIGN ROUTINE APCH ENCOUNTERED THE UNUSUAL WAKE. THE WAKE ENCOUNTER WAS SO UNEXPECTED. THE MD82 AUTOPLT SELF DISCONNECT ALMOST NEVER HAPPENS. THE B727 WAS 8 MI AHEAD AND APPEARED TO BE BELOW EVEN THOUGH IT PROBABLY WAS FOLLOWING THE GS AND WAS AT THE SAME ALT AT THE SAME POINTS ALONG THE ILS. THIS WAS A NORMAL ROUTINE APCH. ALL OF A SUDDEN THE AIRPLANE ROLLED ABRUPTLY 15 DEGS 1 WAY FOLLOWED BY A RAPID ROLL IN THE OTHER DIRECTION, BANKED TO 15 DEGS THE OTHER DIRECTION. THE AUTOPLT DISCONNECTED ITSELF ON THIS SECOND ROLL.

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.