Narrative:

Problem arose due to ATC mishandling. We were on civet arrival and pulled off and changed to mitts arrival for runway 24R. We were told to maintain visual with aircraft below and to our left on final for runway 25L. We advised unable due to cloud deck below that aircraft. ATC then told us to maintain 7000 ft and slow to 150 KTS, a 100 KT reduction. As we were slowing down, we were assigned 5000 ft. With full scale fly-down indication on GS and approximately 8 NM from roman, ATC cleared us for the ILS runway 24R approach. We refused approach as there was no way to adhere to stabilized approach SOP per flight operations manual. We were then vectored north of lczr and cleared to 3000 ft, then later to 2500 ft. Turned onto lczr at 2500 ft and told to intercept. While tracking inbound on lczr, at 2500 ft we were cleared for approach. While on autoplt, I armed approach mode. The aircraft pitched up like it was capturing the GS. I was trying to determine why aircraft was continuing to climb and add thrust and by the time I turned autoplt and autothrottles off, aircraft had climbed to approximately 2850 ft MSL. I immediately started a descent back to 2500 ft. My slow reaction allowed the aircraft to deviate from altitude. Normal aircraft reaction would have been to maintain 2500 ft until intercepting the GS. I believe the autoflt system was reacting improperly due to the racetrack pattern northeast of the final fix.

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Original NASA ASRS Text

Title: LGT CREW WAS PROVIDED POOR ATC HANDLING ON ARR AT LAX.

Narrative: PROB AROSE DUE TO ATC MISHANDLING. WE WERE ON CIVET ARR AND PULLED OFF AND CHANGED TO MITTS ARR FOR RWY 24R. WE WERE TOLD TO MAINTAIN VISUAL WITH ACFT BELOW AND TO OUR L ON FINAL FOR RWY 25L. WE ADVISED UNABLE DUE TO CLOUD DECK BELOW THAT ACFT. ATC THEN TOLD US TO MAINTAIN 7000 FT AND SLOW TO 150 KTS, A 100 KT REDUCTION. AS WE WERE SLOWING DOWN, WE WERE ASSIGNED 5000 FT. WITH FULL SCALE FLY-DOWN INDICATION ON GS AND APPROX 8 NM FROM ROMAN, ATC CLRED US FOR THE ILS RWY 24R APCH. WE REFUSED APCH AS THERE WAS NO WAY TO ADHERE TO STABILIZED APCH SOP PER FLT OPS MANUAL. WE WERE THEN VECTORED N OF LCZR AND CLRED TO 3000 FT, THEN LATER TO 2500 FT. TURNED ONTO LCZR AT 2500 FT AND TOLD TO INTERCEPT. WHILE TRACKING INBOUND ON LCZR, AT 2500 FT WE WERE CLRED FOR APCH. WHILE ON AUTOPLT, I ARMED APCH MODE. THE ACFT PITCHED UP LIKE IT WAS CAPTURING THE GS. I WAS TRYING TO DETERMINE WHY ACFT WAS CONTINUING TO CLB AND ADD THRUST AND BY THE TIME I TURNED AUTOPLT AND AUTOTHROTTLES OFF, ACFT HAD CLBED TO APPROX 2850 FT MSL. I IMMEDIATELY STARTED A DSCNT BACK TO 2500 FT. MY SLOW REACTION ALLOWED THE ACFT TO DEVIATE FROM ALT. NORMAL ACFT REACTION WOULD HAVE BEEN TO MAINTAIN 2500 FT UNTIL INTERCEPTING THE GS. I BELIEVE THE AUTOFLT SYS WAS REACTING IMPROPERLY DUE TO THE RACETRACK PATTERN NE OF THE FINAL FIX.

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.