Narrative:

While in level flight at FL280 on ZID frequency, we received a TCASII TA, followed immediately by a TCASII RA to descend. TCASII directed a descent of approximately 1500 FPM. As we began the descent, I noted that the TCASII indicated that the other aircraft was indicating 700 ft above our altitude. After we had descended approximately 400 ft, the RA terminated. During the TCASII advisory, we called center to indicate that we were responding to the advisory. The controller indicated that he had noted a dip in the altitude, told us to maintain FL280, and contact ZKC. (I am unsure if the previous comment about altitude dip was a reference to our altitude or the other aircraft's altitude.) we did not see the aircraft before or after the TA/RA as we were wbound looking into the sun. After landing, we contacted ZKC via phone.

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Original NASA ASRS Text

Title: B757-200 CREW HAD A TCASII RA IN ZID CLASS A AIRSPACE.

Narrative: WHILE IN LEVEL FLT AT FL280 ON ZID FREQ, WE RECEIVED A TCASII TA, FOLLOWED IMMEDIATELY BY A TCASII RA TO DSND. TCASII DIRECTED A DSCNT OF APPROX 1500 FPM. AS WE BEGAN THE DSCNT, I NOTED THAT THE TCASII INDICATED THAT THE OTHER ACFT WAS INDICATING 700 FT ABOVE OUR ALT. AFTER WE HAD DSNDED APPROX 400 FT, THE RA TERMINATED. DURING THE TCASII ADVISORY, WE CALLED CTR TO INDICATE THAT WE WERE RESPONDING TO THE ADVISORY. THE CTLR INDICATED THAT HE HAD NOTED A DIP IN THE ALT, TOLD US TO MAINTAIN FL280, AND CONTACT ZKC. (I AM UNSURE IF THE PREVIOUS COMMENT ABOUT ALT DIP WAS A REF TO OUR ALT OR THE OTHER ACFT'S ALT.) WE DID NOT SEE THE ACFT BEFORE OR AFTER THE TA/RA AS WE WERE WBOUND LOOKING INTO THE SUN. AFTER LNDG, WE CONTACTED ZKC VIA PHONE.

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.