Narrative:

We were leveling at 10000 ft as per the arrival clearance, when I noticed a target at 6 mi on the outer edge of the TCASII display, 300 ft high and descending. It leveled co-altitude and continued approaching on the same azimuth of about 1 O'clock position at 4 mi. I questioned approach control about the contact and picked up another one at 2 O'clock position, also approaching. At 3 mi, with TA (TA on the TCASII), I initiated a left turn to change the closure. After initiating the turn, we received a climbing RA on the TCASII for a 2000 FPM climb. I continued the left turn and went to a 2000 FPM climb. Approach control then issued their first avoidance vector to a heading 60 degrees left of our original heading. We continued left to that heading and leveled off at 11000 ft (1000 ft high). I found out later that approach control issued the flight of 2 F15's a right turn of 70 degrees and a descent when they were 2-4 mi from our position. I estimate a miss distance of about 1 mi horizontal (or less) and 1000 ft vertical from my last observations on the TCASII display. (We were IMC the entire time.) I credit TCASII information and guidance with avoiding a very disastrous situation.

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Original NASA ASRS Text

Title: MD83 CREW FOLLOWED TCASII RA TO AVOID NMAC WITH FLT OF 2 F15'S.

Narrative: WE WERE LEVELING AT 10000 FT AS PER THE ARR CLRNC, WHEN I NOTICED A TARGET AT 6 MI ON THE OUTER EDGE OF THE TCASII DISPLAY, 300 FT HIGH AND DSNDING. IT LEVELED CO-ALT AND CONTINUED APCHING ON THE SAME AZIMUTH OF ABOUT 1 O'CLOCK POS AT 4 MI. I QUESTIONED APCH CTL ABOUT THE CONTACT AND PICKED UP ANOTHER ONE AT 2 O'CLOCK POS, ALSO APCHING. AT 3 MI, WITH TA (TA ON THE TCASII), I INITIATED A L TURN TO CHANGE THE CLOSURE. AFTER INITIATING THE TURN, WE RECEIVED A CLBING RA ON THE TCASII FOR A 2000 FPM CLB. I CONTINUED THE L TURN AND WENT TO A 2000 FPM CLB. APCH CTL THEN ISSUED THEIR FIRST AVOIDANCE VECTOR TO A HDG 60 DEGS L OF OUR ORIGINAL HDG. WE CONTINUED L TO THAT HDG AND LEVELED OFF AT 11000 FT (1000 FT HIGH). I FOUND OUT LATER THAT APCH CTL ISSUED THE FLT OF 2 F15'S A R TURN OF 70 DEGS AND A DSCNT WHEN THEY WERE 2-4 MI FROM OUR POS. I ESTIMATE A MISS DISTANCE OF ABOUT 1 MI HORIZ (OR LESS) AND 1000 FT VERT FROM MY LAST OBSERVATIONS ON THE TCASII DISPLAY. (WE WERE IMC THE ENTIRE TIME.) I CREDIT TCASII INFO AND GUIDANCE WITH AVOIDING A VERY DISASTROUS 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.