Narrative:

While on radar vectors for an ILS approach at cmh (runway 28) we had an RA on the TCASII which we followed. The situation was as follows: on a heading of 360 degree assigned at 4000 MSL (level) we were issued a heading of 300 degree to intercept the ILS. At that time we saw the landing lights of another aircraft at about 11 to 11:30 position and they appeared to be closing. We asked approach control who the traffic was. They replied that it was air carrier Y following us. At that moment the TCASII gave us a TA alert. The traffic was at the same altitude as us at 11:30 position and closing. The TCASII then changed from a TA to an RA within seconds. The TCASII instructed us to climb which we did and at that time cmh instructed air carrier Y to turn right immediately and also instructed us to do the same. Both aircraft complied. I feel this incident could have been avoided if approach control had issued us a TA before we asked. Time was wasted on communication. At this point we were closing too fast. I called approach control after we landed on the telephone. They explained that we were 2 1/2 - 3 mi apart (same altitude, opposite direction) when we were issued turn instructions. (The TCASII had already issued an RA alert by that time.) I don't like the idea of 2 aircraft being put on a possible collision course, same altitude in a small area such as the approach area. That leaves too much to chance. A radio or radar failure or any other distraction could cause a major conflict.

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Original NASA ASRS Text

Title: LTSS BTWN 2 ACR ACFT. TCASII ALERT. OPERROR. EVASIVE ACTION.

Narrative: WHILE ON RADAR VECTORS FOR AN ILS APCH AT CMH (RWY 28) WE HAD AN RA ON THE TCASII WHICH WE FOLLOWED. THE SITUATION WAS AS FOLLOWS: ON A HDG OF 360 DEG ASSIGNED AT 4000 MSL (LEVEL) WE WERE ISSUED A HDG OF 300 DEG TO INTERCEPT THE ILS. AT THAT TIME WE SAW THE LNDG LIGHTS OF ANOTHER ACFT AT ABOUT 11 TO 11:30 POS AND THEY APPEARED TO BE CLOSING. WE ASKED APCH CTL WHO THE TFC WAS. THEY REPLIED THAT IT WAS ACR Y FOLLOWING US. AT THAT MOMENT THE TCASII GAVE US A TA ALERT. THE TFC WAS AT THE SAME ALT AS US AT 11:30 POS AND CLOSING. THE TCASII THEN CHANGED FROM A TA TO AN RA WITHIN SECONDS. THE TCASII INSTRUCTED US TO CLB WHICH WE DID AND AT THAT TIME CMH INSTRUCTED ACR Y TO TURN R IMMEDIATELY AND ALSO INSTRUCTED US TO DO THE SAME. BOTH ACFT COMPLIED. I FEEL THIS INCIDENT COULD HAVE BEEN AVOIDED IF APCH CTL HAD ISSUED US A TA BEFORE WE ASKED. TIME WAS WASTED ON COM. AT THIS POINT WE WERE CLOSING TOO FAST. I CALLED APCH CTL AFTER WE LANDED ON THE TELEPHONE. THEY EXPLAINED THAT WE WERE 2 1/2 - 3 MI APART (SAME ALT, OPPOSITE DIRECTION) WHEN WE WERE ISSUED TURN INSTRUCTIONS. (THE TCASII HAD ALREADY ISSUED AN RA ALERT BY THAT TIME.) I DON'T LIKE THE IDEA OF 2 ACFT BEING PUT ON A POSSIBLE COLLISION COURSE, SAME ALT IN A SMALL AREA SUCH AS THE APCH AREA. THAT LEAVES TOO MUCH TO CHANCE. A RADIO OR RADAR FAILURE OR ANY OTHER DISTR COULD CAUSE A MAJOR CONFLICT.

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.