Narrative:

Approaching the sli VOR, ATC called traffic we did not see. The frequency was very busy with all types of traffic, and while approaching the sli VOR we received a call for 9 O'clock traffic, altitude unknown. Since my first officer was off the frequency getting the ATIS and making a call to the company, I was left for the moment to fly the aircraft and maintain a visual scan for traffic when the traffic call was made by ATC. Immediately after the call, we complied with a TCASII RA to climb. While complying, I visually contacted the traffic and at the same time, the clear of conflict message was reported by the TCASII. Our altitude was approximately 4600 ft. ATC then made a call to us that was partially blocked, and then followed by a call to a cherokee IFR traffic at 5000 ft, advising them of a TA on our aircraft. After calling ATC on the ground, they told me they were concerned about my altitude deviation, and the subsequent loss of vertical separation between the 2 IFR aircraft. I feel there was no way to avoid this situation. The area was heavily congested with a mix of IFR and VFR aircraft. So much congestion that approximately 3 mins later, we were issued another TCASII RA on another aircraft. Our operations specifications are quite clear that we must comply with a TCASII RA. Since I was not made aware of the IFR traffic at 5000 ft, I had no way of knowing that by complying with the TCASII RA, I was climbing into another aircraft.

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Original NASA ASRS Text

Title: AN ACR LTT HAD TO CLB IN RESPONSE TO A TCASII RA. THIS PUT IT IN CONFLICT WITH AN IFR ACFT ABOVE.

Narrative: APCHING THE SLI VOR, ATC CALLED TFC WE DID NOT SEE. THE FREQ WAS VERY BUSY WITH ALL TYPES OF TFC, AND WHILE APCHING THE SLI VOR WE RECEIVED A CALL FOR 9 O'CLOCK TFC, ALT UNKNOWN. SINCE MY FO WAS OFF THE FREQ GETTING THE ATIS AND MAKING A CALL TO THE COMPANY, I WAS LEFT FOR THE MOMENT TO FLY THE ACFT AND MAINTAIN A VISUAL SCAN FOR TFC WHEN THE TFC CALL WAS MADE BY ATC. IMMEDIATELY AFTER THE CALL, WE COMPLIED WITH A TCASII RA TO CLB. WHILE COMPLYING, I VISUALLY CONTACTED THE TFC AND AT THE SAME TIME, THE CLR OF CONFLICT MESSAGE WAS RPTED BY THE TCASII. OUR ALT WAS APPROX 4600 FT. ATC THEN MADE A CALL TO US THAT WAS PARTIALLY BLOCKED, AND THEN FOLLOWED BY A CALL TO A CHEROKEE IFR TFC AT 5000 FT, ADVISING THEM OF A TA ON OUR ACFT. AFTER CALLING ATC ON THE GND, THEY TOLD ME THEY WERE CONCERNED ABOUT MY ALTDEV, AND THE SUBSEQUENT LOSS OF VERT SEPARATION BTWN THE 2 IFR ACFT. I FEEL THERE WAS NO WAY TO AVOID THIS SIT. THE AREA WAS HEAVILY CONGESTED WITH A MIX OF IFR AND VFR ACFT. SO MUCH CONGESTION THAT APPROX 3 MINS LATER, WE WERE ISSUED ANOTHER TCASII RA ON ANOTHER ACFT. OUR OPS SPECS ARE QUITE CLR THAT WE MUST COMPLY WITH A TCASII RA. SINCE I WAS NOT MADE AWARE OF THE IFR TFC AT 5000 FT, I HAD NO WAY OF KNOWING THAT BY COMPLYING WITH THE TCASII RA, I WAS CLBING INTO ANOTHER ACFT.

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.