Narrative:

The takeoff was made directly into the sun. A 2000 ft altitude was assigned, and in spite of reduced takeoff power being used, the rate of climb was rapid. 'Over the fence' at 900 ft I called '1000 to go.' the first officer called 'vertical speed 1000/flaps 4 degrees/climb power' according to standard procedures. The tower called for us to 'change to departure' and contact was initiated. Finally TCASII RA called 'reduce climb.' all of this occurred nearly simultaneously. The vertical speed indicator showed a green arc between 0 and 400 FPM with a red arc above that. However, the first officer (and so) thought that the aural command was 'climb, climb' so he continued through the 2000 ft restriction. After a second warning, I pushed the stick forward and stopped the climb at about 2300 ft. We never saw the traffic in the glare of the sun. Subsequently TCASII called 'clear of traffic' and departure cleared us to a higher altitude. This TCASII RA occurred during a period of very high workload, as do many of the RA alerts. Not one of us had time to observe and evaluate all of the commands and parameters of the situation. The first officer, a highly competent, alert pilot, focused on the aural command of the TCASII RA. Unfortunately, in the flood of activity and information he misunderstood the command. Or did the TCASII aural warning malfunction? The so, a veteran of 20 yrs flying experience with the military, also thought he heard a 'climb, climb' command. The 2000 ft hold down, the presence of traffic, and the reaction of the TCASII is logical. But under the existing conditions, 3 experienced pilots were unable to agree on an interpretation of the TCASII. When departing high density airports in the future, I will downgrade the importance of flight director/flap/and power commands, definitely anticipate a low altitude capture rather than anticipating a 'continue climb,' and perhaps even turn off the RA function of the TCASII. TCASII is not easy to interpret, especially under high workload conditions. A training aid would be helpful for practice in relating TCASII aural and visual commands to actual situation.

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Original NASA ASRS Text

Title: FLC MISINTERPRETS TCASII AND CLBS TOWARD THE CONFLICT.

Narrative: THE TKOF WAS MADE DIRECTLY INTO THE SUN. A 2000 FT ALT WAS ASSIGNED, AND IN SPITE OF REDUCED TKOF PWR BEING USED, THE RATE OF CLB WAS RAPID. 'OVER THE FENCE' AT 900 FT I CALLED '1000 TO GO.' THE FO CALLED 'VERT SPD 1000/FLAPS 4 DEGS/CLB PWR' ACCORDING TO STANDARD PROCS. THE TWR CALLED FOR US TO 'CHANGE TO DEP' AND CONTACT WAS INITIATED. FINALLY TCASII RA CALLED 'REDUCE CLB.' ALL OF THIS OCCURRED NEARLY SIMULTANEOUSLY. THE VERT SPD INDICATOR SHOWED A GREEN ARC BTWN 0 AND 400 FPM WITH A RED ARC ABOVE THAT. HOWEVER, THE FO (AND SO) THOUGHT THAT THE AURAL COMMAND WAS 'CLB, CLB' SO HE CONTINUED THROUGH THE 2000 FT RESTRICTION. AFTER A SECOND WARNING, I PUSHED THE STICK FORWARD AND STOPPED THE CLB AT ABOUT 2300 FT. WE NEVER SAW THE TFC IN THE GLARE OF THE SUN. SUBSEQUENTLY TCASII CALLED 'CLR OF TFC' AND DEP CLRED US TO A HIGHER ALT. THIS TCASII RA OCCURRED DURING A PERIOD OF VERY HIGH WORKLOAD, AS DO MANY OF THE RA ALERTS. NOT ONE OF US HAD TIME TO OBSERVE AND EVALUATE ALL OF THE COMMANDS AND PARAMETERS OF THE SIT. THE FO, A HIGHLY COMPETENT, ALERT PLT, FOCUSED ON THE AURAL COMMAND OF THE TCASII RA. UNFORTUNATELY, IN THE FLOOD OF ACTIVITY AND INFO HE MISUNDERSTOOD THE COMMAND. OR DID THE TCASII AURAL WARNING MALFUNCTION? THE SO, A VETERAN OF 20 YRS FLYING EXPERIENCE WITH THE MIL, ALSO THOUGHT HE HEARD A 'CLB, CLB' COMMAND. THE 2000 FT HOLD DOWN, THE PRESENCE OF TFC, AND THE REACTION OF THE TCASII IS LOGICAL. BUT UNDER THE EXISTING CONDITIONS, 3 EXPERIENCED PLTS WERE UNABLE TO AGREE ON AN INTERP OF THE TCASII. WHEN DEPARTING HIGH DENSITY ARPTS IN THE FUTURE, I WILL DOWNGRADE THE IMPORTANCE OF FLT DIRECTOR/FLAP/AND PWR COMMANDS, DEFINITELY ANTICIPATE A LOW ALT CAPTURE RATHER THAN ANTICIPATING A 'CONTINUE CLB,' AND PERHAPS EVEN TURN OFF THE RA FUNCTION OF THE TCASII. TCASII IS NOT EASY TO INTERPRET, ESPECIALLY UNDER HIGH WORKLOAD CONDITIONS. A TRAINING AID WOULD BE HELPFUL FOR PRACTICE IN RELATING TCASII AURAL AND VISUAL COMMANDS TO ACTUAL SIT.

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.