Narrative:

After leveling at 11000 ft MSL on the aqn-2 arrival to dfw and heading northeast on the aqn 040 degree radial at 18 DME, I received a TCASII TA. After checking the TCASII display, I looked ahead to visually acquire the intruder target. I visually sighted an medium large transport at my 11:30 O'clock climbing towards my aircraft. I then received a TCASII RA which instructed me to climb at 1500 FPM. I complied with the RA and climbed 500 ft above my assigned altitude when the TCASII issued the clear of conflict aural. During the climb, I notified ATC that I was leaving my assigned altitude to comply with the TCASII RA. Controller asked if we saw the target ahead. I stated that I indeed had the target visually. Controller stated the target was assigned to level at 10000 ft MSL. He also asked why I was deviating from assigned altitude since I had visually sighted target. I told him that my company's policy is to follow every RA to the letter unless the RA would result in a danger to the aircraft. The controller then said 'well, you'll be hearing about this one. Call approach on (next frequency).' I believe the RA I received was issued as a classic example of the 'dfw bump' caused by large climb and descent rates aircraft fly here. Current TCASII software doesn't recognize these rates as normal and issues many bogus RA's. However, by law, I am forced to trust my instruments and comply with all RA's. Controllers must understand that a visual sighting does not relieve me of that responsibility. A collision can just as easily occur between visual targets as those unseen. The safest action to take is to comply with an RA.

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Original NASA ASRS Text

Title: MLG FLC RESPONDS TO TCASII RA. ALTDEV.

Narrative: AFTER LEVELING AT 11000 FT MSL ON THE AQN-2 ARR TO DFW AND HDG NE ON THE AQN 040 DEG RADIAL AT 18 DME, I RECEIVED A TCASII TA. AFTER CHKING THE TCASII DISPLAY, I LOOKED AHEAD TO VISUALLY ACQUIRE THE INTRUDER TARGET. I VISUALLY SIGHTED AN MLG AT MY 11:30 O'CLOCK CLBING TOWARDS MY ACFT. I THEN RECEIVED A TCASII RA WHICH INSTRUCTED ME TO CLB AT 1500 FPM. I COMPLIED WITH THE RA AND CLBED 500 FT ABOVE MY ASSIGNED ALT WHEN THE TCASII ISSUED THE CLR OF CONFLICT AURAL. DURING THE CLB, I NOTIFIED ATC THAT I WAS LEAVING MY ASSIGNED ALT TO COMPLY WITH THE TCASII RA. CTLR ASKED IF WE SAW THE TARGET AHEAD. I STATED THAT I INDEED HAD THE TARGET VISUALLY. CTLR STATED THE TARGET WAS ASSIGNED TO LEVEL AT 10000 FT MSL. HE ALSO ASKED WHY I WAS DEVIATING FROM ASSIGNED ALT SINCE I HAD VISUALLY SIGHTED TARGET. I TOLD HIM THAT MY COMPANY'S POLICY IS TO FOLLOW EVERY RA TO THE LETTER UNLESS THE RA WOULD RESULT IN A DANGER TO THE ACFT. THE CTLR THEN SAID 'WELL, YOU'LL BE HEARING ABOUT THIS ONE. CALL APCH ON (NEXT FREQ).' I BELIEVE THE RA I RECEIVED WAS ISSUED AS A CLASSIC EXAMPLE OF THE 'DFW BUMP' CAUSED BY LARGE CLB AND DSCNT RATES ACFT FLY HERE. CURRENT TCASII SOFTWARE DOESN'T RECOGNIZE THESE RATES AS NORMAL AND ISSUES MANY BOGUS RA'S. HOWEVER, BY LAW, I AM FORCED TO TRUST MY INSTS AND COMPLY WITH ALL RA'S. CTLRS MUST UNDERSTAND THAT A VISUAL SIGHTING DOES NOT RELIEVE ME OF THAT RESPONSIBILITY. A COLLISION CAN JUST AS EASILY OCCUR BTWN VISUAL TARGETS AS THOSE UNSEEN. THE SAFEST ACTION TO TAKE IS TO COMPLY WITH AN RA.

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.