Narrative:

While on visual approach to runway 30 lgb received 'GS' aural warning during last 100-150 ft while over runway (2576 ft of displaced threshold); touchdown was at 1000 ft marker on runway. Reference speed: 138 KTS; target speed 143 KTS. Autobrakes set to 4. During this approach/landing; wind was 270 degrees at 16 KTS and a bit gusty. Numerous light aircraft in and around airport traffic pattern. Tower had advised us of traffic in l-hand pattern for runway 25L that would cross over us during our approach. I was PF and had the autoplt on and coupled to the ILS approach as I normally do at this airport to aid in visually identing traffic warnings on TCAS. We had at least 2 amber flashing warning during last 500 ft of approach. Approximately 200 ft AGL; I noticed we were drifting left of centerline; so I disconnected the autoplt and corrected back to center. I then looked up at traffic about to cross overhead (a small cessna in the pattern for runway 25L which was one of the amber TCAS aircraft). During this distraction; we enter a sink which took us below glide path (first officer called 1 DOT low). My focus was then visual looking at the runway aim point thousand ft markers. We were over the displaced threshold and the GPWS aural 'GS' warning activated. I was totally focused on the visual aim point and was certain we would touch down beyond the threshold; so I continued to landing and we touched down at the 1000 ft markers. I have flown this approach many; many times. There is only 6324 ft of runway beyond the GS touchdown point. I have experienced touchdowns beyond this point (both as PF and pilot monitoring) which resulted in heavy braking to stop on remaining runway. The 2576 ft of displaced threshold is very unusual for a runway of this length (10000 ft). I tend to focus on ensuring wheels touch down on the 1000 ft markers here more than any other airport I can think of. It was; however; the first time I experienced the aural 'GS' warning. At any other airport/approach I would have not hesitated to go around. Contributing factors: numerous TCAS warnings to the lgb's practice of allowing aircraft to cross overhead of us while on approach to runway 30 -- it's very distracting. Somewhat gusty wind conditions (which contributed to our sink below the GS). The usually long displaced threshold. The 6324 ft beyond the GS touchdown point (short for a heavy aircraft).

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Original NASA ASRS Text

Title: A HEAVY TRANSPORT ON APPROACH TO LGB FLEW AN UNSTABILIZED APPROACH AND GOT A 'GLIDE SLOPE' AURAL WARNING.

Narrative: WHILE ON VISUAL APCH TO RWY 30 LGB RECEIVED 'GS' AURAL WARNING DURING LAST 100-150 FT WHILE OVER RWY (2576 FT OF DISPLACED THRESHOLD); TOUCHDOWN WAS AT 1000 FT MARKER ON RWY. REF SPD: 138 KTS; TARGET SPD 143 KTS. AUTOBRAKES SET TO 4. DURING THIS APCH/LNDG; WIND WAS 270 DEGS AT 16 KTS AND A BIT GUSTY. NUMEROUS LIGHT ACFT IN AND AROUND ARPT TFC PATTERN. TWR HAD ADVISED US OF TFC IN L-HAND PATTERN FOR RWY 25L THAT WOULD CROSS OVER US DURING OUR APCH. I WAS PF AND HAD THE AUTOPLT ON AND COUPLED TO THE ILS APCH AS I NORMALLY DO AT THIS ARPT TO AID IN VISUALLY IDENTING TFC WARNINGS ON TCAS. WE HAD AT LEAST 2 AMBER FLASHING WARNING DURING LAST 500 FT OF APCH. APPROX 200 FT AGL; I NOTICED WE WERE DRIFTING L OF CTRLINE; SO I DISCONNECTED THE AUTOPLT AND CORRECTED BACK TO CTR. I THEN LOOKED UP AT TFC ABOUT TO CROSS OVERHEAD (A SMALL CESSNA IN THE PATTERN FOR RWY 25L WHICH WAS ONE OF THE AMBER TCAS ACFT). DURING THIS DISTR; WE ENTER A SINK WHICH TOOK US BELOW GLIDE PATH (FO CALLED 1 DOT LOW). MY FOCUS WAS THEN VISUAL LOOKING AT THE RWY AIM POINT THOUSAND FT MARKERS. WE WERE OVER THE DISPLACED THRESHOLD AND THE GPWS AURAL 'GS' WARNING ACTIVATED. I WAS TOTALLY FOCUSED ON THE VISUAL AIM POINT AND WAS CERTAIN WE WOULD TOUCH DOWN BEYOND THE THRESHOLD; SO I CONTINUED TO LNDG AND WE TOUCHED DOWN AT THE 1000 FT MARKERS. I HAVE FLOWN THIS APCH MANY; MANY TIMES. THERE IS ONLY 6324 FT OF RWY BEYOND THE GS TOUCHDOWN POINT. I HAVE EXPERIENCED TOUCHDOWNS BEYOND THIS POINT (BOTH AS PF AND PLT MONITORING) WHICH RESULTED IN HVY BRAKING TO STOP ON REMAINING RWY. THE 2576 FT OF DISPLACED THRESHOLD IS VERY UNUSUAL FOR A RWY OF THIS LENGTH (10000 FT). I TEND TO FOCUS ON ENSURING WHEELS TOUCH DOWN ON THE 1000 FT MARKERS HERE MORE THAN ANY OTHER ARPT I CAN THINK OF. IT WAS; HOWEVER; THE FIRST TIME I EXPERIENCED THE AURAL 'GS' WARNING. AT ANY OTHER ARPT/APCH I WOULD HAVE NOT HESITATED TO GO AROUND. CONTRIBUTING FACTORS: NUMEROUS TCAS WARNINGS TO THE LGB'S PRACTICE OF ALLOWING ACFT TO CROSS OVERHEAD OF US WHILE ON APCH TO RWY 30 -- IT'S VERY DISTRACTING. SOMEWHAT GUSTY WIND CONDITIONS (WHICH CONTRIBUTED TO OUR SINK BELOW THE GS). THE USUALLY LONG DISPLACED THRESHOLD. THE 6324 FT BEYOND THE GS TOUCHDOWN POINT (SHORT FOR A HVY ACFT).

Data retrieved from NASA's ASRS site as of May 2009 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.