FLC OF AN MLG ACR ACFT STOPPED THEIR DSCNT AND CLBED IN RESPONSE TO A GPWS WARNING WHILE DSNDING TO ASSIGNED APCH ALT.

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WHILE DSNDING INTO CHATTANOOGA; TN; (CHA) WE EXPERIENCED A GND PROX WARNING (GPWS). I WAS 210 KTS PASSING 3300 FT MSL WITH MY AUTOPLT IN A CAPTURE MODE TO 3000 FT MSL. WE WERE IN A BROKEN DECK OF CLOUDS AND IN THE CLR PARTS WE COULD SEE THE GND. THE GPWS COMMUNICATED 'TERRAIN' WARNING AND I IMMEDIATELY KICKED THE AUTOPLT AND AUTOTHROTTLES OFF AND PUSHED THE PWR UP AND STARTED A CLB. WE NEVER REACHED 3000 FT MSL AND CLBED UP TO 3500 FT MSL BEFORE THE GPWS STOPPED ITS WARNING. WE TOLD APCH (CHATTANOOGA) THAT WE HAD RECEIVED A TERRAIN WARNING DSNDING TO 3000 MSL. HE CHKED THE MSA AND OBSTRUCTIONS AND SAID THERE SHOULD HAVE BEEN NO PROB. THE REST OF THE APCH AND LNDG WERE UNEVENTFUL. WE HAD BEEN TRAVELLING CLOSE TO DIRECT FROM NOONE (N FIX N OF ATC) TO DIRECT TO CHA. WE WERE APPROX 15 NM FROM THE FIELD (CHA) AND ON A NORTHERLY HDG. WE WERE STILL OVER THE RIDGE LINE WHEN THE ALERT OCCURRED. WHEN DEPARTING THE ACFT I MENTIONED TO THE FIRST CLASS FLT ATTENDANT IF SHE HAD HEARD THE GPWS WARNING 'TERRAIN.' SHE HAD; AND IN FACT HAD HEARD IT SEVERAL OTHER FLTS THAT MONTH FROM ATL TO CHA. I WOULD ASSUME THAT THIS WASN'T AN ISOLATED INCIDENT. I AM WONDERING IF THE MSA AT THAT SPOT IS TOO LOW OR THERE IS SOME KIND OF OBSTRUCTION TRIGGERING THE GPWS ALERT. THIS WOULD BE AN EYE OPENER IF IT OCCURS TO SOMEONE IN IMC.