Narrative:

B727 flight rsw-cvg on schedule, approximately mach .80 (normal speed). Switched up ZTL around atl VORTAC, while on course direct to vxv and rest of flight plan route. Checked in at FL290 and was told to expect FL280 shortly now turn right further 20 degree vector. After completing that turn, approximately 350 degree heading, our TCASII verbally alerted 'traffic.' it was set at 50 NM range and displayed '00' in yellow at 11:30 O'clock position about 40 mi off our nose. I flipped the range to 5 NM and almost immediately, with the TCASII saying 'traffic,' a yellow '00' appeared at about 11:30 O'clock position. All eyes scanned forward. Captain radioed center about traffic, no response. TCASII then alerted 'climb.' (I was predisposed for this as I had my hands on the yoke and throttles due to concern over a '00' target at 12 O'clock position on 5 mi range.) I would guess 10 seconds for the 'climb' to annunciate, clicked off the autoplt, pulled back on the yoke and position the throttles up 1, vsi now read 1800 FPM up and about FL293 I saw a shadow flash out my side (right) window. We topped at FL303. Contacted center (3 tries) to report our maneuver and ask was that a 'real' target. He reluctantly said it was and we were now cleared back to FL290. (The seat belt sign was on, and flight attendants reported no passenger seemed aware of the maneuver.) center never seemed overloaded -- but I think he thought he had given us FL280 instead of 'expect.' I'm not so sure 'expect' phrasing helps anyone -- except for late crossing restrs. Glad that TCASII did it's job.

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Original NASA ASRS Text

Title: NMAC BTWN A B727-200 IN LEVEL FLT AND AN UNKNOWN ACFT AT FL290. THE FLC OF THE B727 CLBED IN RESPONSE TO TCASII RA JUST IN TIME TO AVOID A POSSIBLE COLLISION.

Narrative: B727 FLT RSW-CVG ON SCHEDULE, APPROX MACH .80 (NORMAL SPD). SWITCHED UP ZTL AROUND ATL VORTAC, WHILE ON COURSE DIRECT TO VXV AND REST OF FLT PLAN RTE. CHKED IN AT FL290 AND WAS TOLD TO EXPECT FL280 SHORTLY NOW TURN R FURTHER 20 DEG VECTOR. AFTER COMPLETING THAT TURN, APPROX 350 DEG HDG, OUR TCASII VERBALLY ALERTED 'TFC.' IT WAS SET AT 50 NM RANGE AND DISPLAYED '00' IN YELLOW AT 11:30 O'CLOCK POS ABOUT 40 MI OFF OUR NOSE. I FLIPPED THE RANGE TO 5 NM AND ALMOST IMMEDIATELY, WITH THE TCASII SAYING 'TFC,' A YELLOW '00' APPEARED AT ABOUT 11:30 O'CLOCK POS. ALL EYES SCANNED FORWARD. CAPT RADIOED CTR ABOUT TFC, NO RESPONSE. TCASII THEN ALERTED 'CLB.' (I WAS PREDISPOSED FOR THIS AS I HAD MY HANDS ON THE YOKE AND THROTTLES DUE TO CONCERN OVER A '00' TARGET AT 12 O'CLOCK POS ON 5 MI RANGE.) I WOULD GUESS 10 SECONDS FOR THE 'CLB' TO ANNUNCIATE, CLICKED OFF THE AUTOPLT, PULLED BACK ON THE YOKE AND POS THE THROTTLES UP 1, VSI NOW READ 1800 FPM UP AND ABOUT FL293 I SAW A SHADOW FLASH OUT MY SIDE (R) WINDOW. WE TOPPED AT FL303. CONTACTED CTR (3 TRIES) TO RPT OUR MANEUVER AND ASK WAS THAT A 'REAL' TARGET. HE RELUCTANTLY SAID IT WAS AND WE WERE NOW CLRED BACK TO FL290. (THE SEAT BELT SIGN WAS ON, AND FLT ATTENDANTS RPTED NO PAX SEEMED AWARE OF THE MANEUVER.) CTR NEVER SEEMED OVERLOADED -- BUT I THINK HE THOUGHT HE HAD GIVEN US FL280 INSTEAD OF 'EXPECT.' I'M NOT SO SURE 'EXPECT' PHRASING HELPS ANYONE -- EXCEPT FOR LATE XING RESTRS. GLAD THAT TCASII DID IT'S JOB.

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.