Narrative:

Climbing out of mobile, al, en route to shreveport, la, autoplt and automatic throttles engaged, on a heading to intercept a track from mobile to mccomb, ms. FMS was armed to intercept this track. While climbing through 11000 and accelerating through 320 KIAS, the TCASII audio gave a 'traffic' warning. A visual check of the TCASII/radar indicator revealed a round yellow target at 11 O'clock, 900 ft below us climbing. A few moments later, TCASII audio issued a 'descend now' command. Autoplt and automatic throttles were disconnected. A gradual pitch over of the aircraft resulted in an airframe shudder. I thought this shudder was due to the loading on the stabilizer since it was trimmed for a climb. During the evasive maneuver, I/we spotted the aircraft. It appeared to be a 2 engine, white in color, military jet (possibly a jet similar to the aircraft based at the coast guard station at mobile). I changed heading slightly to the left because the target aircraft was at or near our altitude. We descended approximately 800 ft, by which time the 'clear of conflict' annunciation was heard. In response to our query, the controller at houston ARTCC stated he was not in contact with the conflict target, and the controller added he did not advise us of this target because it was at 9500 ft and he saw no problem until the aircraft suddenly climbed and by the time the controller recognized a problem existed, it was too late for him to say anything.

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Original NASA ASRS Text

Title: TCASII RA. FLC RESPONDS.

Narrative: CLBING OUT OF MOBILE, AL, ENRTE TO SHREVEPORT, LA, AUTOPLT AND AUTO THROTTLES ENGAGED, ON A HDG TO INTERCEPT A TRACK FROM MOBILE TO MCCOMB, MS. FMS WAS ARMED TO INTERCEPT THIS TRACK. WHILE CLBING THROUGH 11000 AND ACCELERATING THROUGH 320 KIAS, THE TCASII AUDIO GAVE A 'TFC' WARNING. A VISUAL CHK OF THE TCASII/RADAR INDICATOR REVEALED A ROUND YELLOW TARGET AT 11 O'CLOCK, 900 FT BELOW US CLBING. A FEW MOMENTS LATER, TCASII AUDIO ISSUED A 'DSND NOW' COMMAND. AUTOPLT AND AUTO THROTTLES WERE DISCONNECTED. A GRADUAL PITCH OVER OF THE ACFT RESULTED IN AN AIRFRAME SHUDDER. I THOUGHT THIS SHUDDER WAS DUE TO THE LOADING ON THE STABILIZER SINCE IT WAS TRIMMED FOR A CLB. DURING THE EVASIVE MANEUVER, I/WE SPOTTED THE ACFT. IT APPEARED TO BE A 2 ENG, WHITE IN COLOR, MIL JET (POSSIBLY A JET SIMILAR TO THE ACFT BASED AT THE COAST GUARD STATION AT MOBILE). I CHANGED HDG SLIGHTLY TO THE L BECAUSE THE TARGET ACFT WAS AT OR NEAR OUR ALT. WE DSNDED APPROX 800 FT, BY WHICH TIME THE 'CLR OF CONFLICT' ANNUNCIATION WAS HEARD. IN RESPONSE TO OUR QUERY, THE CTLR AT HOUSTON ARTCC STATED HE WAS NOT IN CONTACT WITH THE CONFLICT TARGET, AND THE CTLR ADDED HE DID NOT ADVISE US OF THIS TARGET BECAUSE IT WAS AT 9500 FT AND HE SAW NO PROBLEM UNTIL THE ACFT SUDDENLY CLBED AND BY THE TIME THE CTLR RECOGNIZED A PROBLEM EXISTED, IT WAS TOO LATE FOR HIM TO SAY ANYTHING.

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.