Narrative:

While climbing out of iah, our TCASII alerted us to traffic (TA) at (1200 ft) less than 5 NM (9:30 O'clock), followed immediately bh an (RA) for (900 ft) less than 2 mi, still climbing in excess of 500 FPM. Medium large transport Y, outbound from hobby (hou) was climbing to (?) altitude on a west heading. He was supposed to level off before our altitude (we were climbing to 15000 ft MSL). We were never appraised by iah departure control that traffic was approaching us from the left. We followed the RA to 'descend, descend, descend'. Almost immediately, the RA was __________ to 'increase descent'. We immediately began a descending right turn to separate us from the traffic down to 10100 ft MSL. Later, we were told that at closest point we had been rather close. The ATC admitted his error in not bringing us (medium large transport X) into the information loop, which necessitated our maneuvering the aircraft so as to avoid a life threatening situation. Had he (ATC) informed us of medium large transport Y position and intentions, we may have been able to use the TCAS information differently. As it was, we used the information and tools at hand and executed the appropriate procedure to safely avoid injury to all parties. I submit this report to help in the study of TCAS incidents. Supplemental information from acn 183615: while on climb out from kiah at the iah 210 degree radial/30 DME point, out TCAS alerted us to a TA target at our 9-10 O'clock position. The target was 1400 ft below us and climbing. The TCAS then alerted us with an RA instructing us to 'descend'. I estimated our altitude at this time to be approximately 11300 ft. Upon receiving the RA instruction I began to lower the nose of the aircraft and made visual contact with the target. I could see that the target aircraft was indeed climbing so I initiated an immediate descent and turn away. The TCAS now began to announce 'increase descent'. Then, once established in my descent, the TCAS began to announce 'climb'. Because I still had the target aircraft in sight and the fact that I was well established in a descent of approximately 4500 FPM, I elected to disregard the 'climb' commanded by the TCAS and continue visual separation between my aircraft and the target aircraft. I observed the target aircraft cross directly over head our aircraft from our 10 O'clock position, left to right. Our altitude at this point was approximately 10100 ft. Once the target aircraft was no longer a threat, I reestablished a normal climb profile and completed the flight to mmex without further incident. An additional witness to this incident is a FSS with the FAA and was occupying our cockpit jumpseat.

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Original NASA ASRS Text

Title: ACR MLG CAPT REACTS TO TCASII TA AND CREATES A POTENTIAL CONFLICT LTSS INCIDENT.

Narrative: WHILE CLBING OUT OF IAH, OUR TCASII ALERTED US TO TFC (TA) AT (1200 FT) LESS THAN 5 NM (9:30 O'CLOCK), FOLLOWED IMMEDIATELY BH AN (RA) FOR (900 FT) LESS THAN 2 MI, STILL CLBING IN EXCESS OF 500 FPM. MLG Y, OUTBOUND FROM HOBBY (HOU) WAS CLBING TO (?) ALT ON A W HDG. HE WAS SUPPOSED TO LEVEL OFF BEFORE OUR ALT (WE WERE CLBING TO 15000 FT MSL). WE WERE NEVER APPRAISED BY IAH DEP CTL THAT TFC WAS APCHING US FROM THE L. WE FOLLOWED THE RA TO 'DSND, DSND, DSND'. ALMOST IMMEDIATELY, THE RA WAS __________ TO 'INCREASE DSCNT'. WE IMMEDIATELY BEGAN A DSNDING R TURN TO SEPARATE US FROM THE TFC DOWN TO 10100 FT MSL. LATER, WE WERE TOLD THAT AT CLOSEST POINT WE HAD BEEN RATHER CLOSE. THE ATC ADMITTED HIS ERROR IN NOT BRINGING US (MLG X) INTO THE INFO LOOP, WHICH NECESSITATED OUR MANEUVERING THE ACFT SO AS TO AVOID A LIFE THREATENING SITUATION. HAD HE (ATC) INFORMED US OF MLG Y POS AND INTENTIONS, WE MAY HAVE BEEN ABLE TO USE THE TCAS INFO DIFFERENTLY. AS IT WAS, WE USED THE INFO AND TOOLS AT HAND AND EXECUTED THE APPROPRIATE PROC TO SAFELY AVOID INJURY TO ALL PARTIES. I SUBMIT THIS RPT TO HELP IN THE STUDY OF TCAS INCIDENTS. SUPPLEMENTAL INFO FROM ACN 183615: WHILE ON CLB OUT FROM KIAH AT THE IAH 210 DEG RADIAL/30 DME POINT, OUT TCAS ALERTED US TO A TA TARGET AT OUR 9-10 O'CLOCK POS. THE TARGET WAS 1400 FT BELOW US AND CLBING. THE TCAS THEN ALERTED US WITH AN RA INSTRUCTING US TO 'DSND'. I ESTIMATED OUR ALT AT THIS TIME TO BE APPROX 11300 FT. UPON RECEIVING THE RA INSTRUCTION I BEGAN TO LOWER THE NOSE OF THE ACFT AND MADE VISUAL CONTACT WITH THE TARGET. I COULD SEE THAT THE TARGET ACFT WAS INDEED CLBING SO I INITIATED AN IMMEDIATE DSCNT AND TURN AWAY. THE TCAS NOW BEGAN TO ANNOUNCE 'INCREASE DSCNT'. THEN, ONCE ESTABLISHED IN MY DSCNT, THE TCAS BEGAN TO ANNOUNCE 'CLB'. BECAUSE I STILL HAD THE TARGET ACFT IN SIGHT AND THE FACT THAT I WAS WELL ESTABLISHED IN A DSCNT OF APPROX 4500 FPM, I ELECTED TO DISREGARD THE 'CLB' COMMANDED BY THE TCAS AND CONTINUE VISUAL SEPARATION BTWN MY ACFT AND THE TARGET ACFT. I OBSERVED THE TARGET ACFT CROSS DIRECTLY OVER HEAD OUR ACFT FROM OUR 10 O'CLOCK POS, L TO R. OUR ALT AT THIS POINT WAS APPROX 10100 FT. ONCE THE TARGET ACFT WAS NO LONGER A THREAT, I REESTABLISHED A NORMAL CLB PROFILE AND COMPLETED THE FLT TO MMEX WITHOUT FURTHER INCIDENT. AN ADDITIONAL WITNESS TO THIS INCIDENT IS A FSS WITH THE FAA AND WAS OCCUPYING OUR COCKPIT JUMPSEAT.

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.