Narrative:

This incident (or series of incidents) took place on a short ferry flight from lgb to lax. The airplane was very light as it was empty and only 17000# in the tanks, so the performance was very high. Because of noise restrictions, we decided to use full power (maximum EPR) takeoff and a V2+10 climb out to 1500' and then a power reduction to about 1.52 EPR for the remainder of our climb out to our cleared altitude of 2000' using 5 degree flaps to level off and maneuvering for the approach to lax. This day was a weekend and it seemed like dozens of light GA aircraft (lga aircraft) were swarming around the lgb airport using both runways 25L and 25R. We were cleared to takeoff on runway 30. As we added power for takeoff, the aircraft accelerated very rapidly to V1VR+V2 speeds (due to light weight) and after very few seconds into the takeoff roll, the second officer pointed out a lga aircraft immediately ahead of us at about 1000' AGL. I almost decided to abort the takeoff at that time, but a second or two later the lga aircraft appeared to be in a right turn to downwind for runway 25R and began to move to the right away from our flight path, so I continued the takeoff. Because of the distraction and worry about the lga aircraft, I did not notice or keep track of the rapidly accelerating airspeed on the takeoff roll and missed the V1VR and V2 callouts. In the meantime, because of increasing airspeed, the airplane began to pitch up and the first officer, sensing that the aircraft was tail heavy, began to trim the stabilizer nose down (the cg was very far aft with a stabilizer trim setting of about 3 nose up units) and because of that the takeoff warning horn sounded (trim out of green band). Because of my concern and distraction with the lga aircraft, I was not aware that the first officer had changed the stabilizer setting while still on the ground at some airspeed which was probably in excess of V1. I then (as programmed many times in training when the takeoff warn horn sounds) began to reduce power to abort, but both first officer and second officer correctly advised me that it was too late to abort and that the trim had been changed. So, takeoff was continued with no further problem.

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Original NASA ASRS Text

Title: TKOF WARNING HORN SOUNDS DURING TKOF ALMOST CAUSING AN ABORT BEYOND V1 SPEED.

Narrative: THIS INCIDENT (OR SERIES OF INCIDENTS) TOOK PLACE ON A SHORT FERRY FLT FROM LGB TO LAX. THE AIRPLANE WAS VERY LIGHT AS IT WAS EMPTY AND ONLY 17000# IN THE TANKS, SO THE PERFORMANCE WAS VERY HIGH. BECAUSE OF NOISE RESTRICTIONS, WE DECIDED TO USE FULL PWR (MAX EPR) TKOF AND A V2+10 CLBOUT TO 1500' AND THEN A PWR REDUCTION TO ABOUT 1.52 EPR FOR THE REMAINDER OF OUR CLBOUT TO OUR CLRED ALT OF 2000' USING 5 DEG FLAPS TO LEVEL OFF AND MANEUVERING FOR THE APCH TO LAX. THIS DAY WAS A WEEKEND AND IT SEEMED LIKE DOZENS OF LIGHT GA ACFT (LGA ACFT) WERE SWARMING AROUND THE LGB ARPT USING BOTH RWYS 25L AND 25R. WE WERE CLRED TO TKOF ON RWY 30. AS WE ADDED PWR FOR TKOF, THE ACFT ACCELERATED VERY RAPIDLY TO V1VR+V2 SPDS (DUE TO LIGHT WT) AND AFTER VERY FEW SECS INTO THE TKOF ROLL, THE S/O POINTED OUT A LGA ACFT IMMEDIATELY AHEAD OF US AT ABOUT 1000' AGL. I ALMOST DECIDED TO ABORT THE TKOF AT THAT TIME, BUT A SECOND OR TWO LATER THE LGA ACFT APPEARED TO BE IN A RIGHT TURN TO DOWNWIND FOR RWY 25R AND BEGAN TO MOVE TO THE RIGHT AWAY FROM OUR FLT PATH, SO I CONTINUED THE TKOF. BECAUSE OF THE DISTR AND WORRY ABOUT THE LGA ACFT, I DID NOT NOTICE OR KEEP TRACK OF THE RAPIDLY ACCELERATING AIRSPD ON THE TKOF ROLL AND MISSED THE V1VR AND V2 CALLOUTS. IN THE MEANTIME, BECAUSE OF INCREASING AIRSPD, THE AIRPLANE BEGAN TO PITCH UP AND THE F/O, SENSING THAT THE ACFT WAS TAIL HEAVY, BEGAN TO TRIM THE STABILIZER NOSE DOWN (THE CG WAS VERY FAR AFT WITH A STABILIZER TRIM SETTING OF ABOUT 3 NOSE UP UNITS) AND BECAUSE OF THAT THE TKOF WARNING HORN SOUNDED (TRIM OUT OF GREEN BAND). BECAUSE OF MY CONCERN AND DISTR WITH THE LGA ACFT, I WAS NOT AWARE THAT THE F/O HAD CHANGED THE STABILIZER SETTING WHILE STILL ON THE GND AT SOME AIRSPD WHICH WAS PROBABLY IN EXCESS OF V1. I THEN (AS PROGRAMMED MANY TIMES IN TRNING WHEN THE TKOF WARN HORN SOUNDS) BEGAN TO REDUCE PWR TO ABORT, BUT BOTH F/O AND S/O CORRECTLY ADVISED ME THAT IT WAS TOO LATE TO ABORT AND THAT THE TRIM HAD BEEN CHANGED. SO, TKOF WAS CONTINUED WITH NO FURTHER PROB.

Data retrieved from NASA's ASRS site as of August 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.