E145 FLT CREW DSNDS EARLY ON ILS RWY 17C AT DFW.

Narrative

OUR ACR X WAS CLRED TO 4000 FT; INTERCEPTED THE LOC AND WAS CLRED FOR THE APCH RWY 17C AT DFW. I WAS THE PNF HANDLING THE RADIO CALLS AND RUNNING THE CHKLISTS. AS I WAS COMPLETING THE APCH CHKLIST; FINAL MONITOR CAME ON THE RADIO AND STATED ACR X HAD BEEN INSTRUCTED TO MAINTAIN 4000 FT UNTIL PENNY INTXN. AT THAT MOMENT I LOOKED UP FROM THE CHKLIST TO SEE THAT WE WERE INSIDE PENNY; COMING UPON ZINGG; AT AN ALT OF 3300 FT WITH 3000 FT SET IN THE ALT SELECTOR. THE FO WHO WAS FLYING HAD SELECTED 3000 FT AND WAS IN THE PROCESS FO SELECTING 2500 FT IN THE ALT SELECTOR. WE WERE BELOW GS. ALTHOUGH I DO NOT RECALL ANY INSTRUCTION TO MAINTAIN 4000 FT UNTIL PENNY INTXN; THE APCH PLATE SHOWED 4000 FT. IMMEDIATELY; I INSTRUCTED THE FO TO CLB TO GS. WE WERE AT 4000 FT WHEN I BEGAN THE CHKLIST. SINCE THE FO CHANGED THE ALT SELECTOR WITHOUT NOTIFYING ME; THERE WAS NO CHIME FOR THE ALTDEV. AT WHAT MOMENT THE FO LEFT 4000 FT I AM NOT CERTAIN. HOWEVER; IT COULD NOT HAVE BEEN VERY FAR FROM PENNY INTXN. UPON MY INSTRUCTION; THE FO PROCEEDED TO CLB TO GS AND PROCEEDED WITH NORMAL ILS. ONCE WE HAD BLOCKED IN AT THE GATE; I DISCUSSED THE APCH WITH THE FO. HE TOLD ME THAT HE WAS THINKING LOC APCH WITH DSCNT TO VISUAL CONDITIONS. RWY 17C AT DFW HAS BEEN UNDER CONSTRUCTION FOR SOME TIME WITH THE ILS RWY 17C DECOMMISSIONED. WE HAVE BEEN FLYING THE LOC TO VISUAL FOR SEVERAL MONTHS. THE NEW ILS WAS COMMISSIONED JUST RECENTLY WITH THE OPENING OF FULL LENGTH RWY 17C. ALTHOUGH WE HAD DISCUSSED THIS IN OUR APCH BRIEFING; THE FO WAS STILL THINKING VISUAL APCH. AT 4000 FT; WE WERE IN THE BASE OF SCATTERED CLOUDS. BASES WERE AT 3800 FT WITH 7 MI VISIBILITY. IN THE FO'S MIND; ONCE HE WAS CLRED FOR THE APCH; HE WAS CLRED TO START HIS DSCNT TO VFR CONDITIONS. WE WERE CLRED FOR THE NEW ILS RWY 17C AS WAS PROGRAMMED INTO THE RADIOS. WE DISCUSSED IN DETAIL THE PROB CREATED WHEN THE FO CHANGED THE ALT SELECTOR WITHOUT TELLING ME. WE DISCUSSED HOW THE FO'S ACTIONS REMOVED ME FROM THE LOOP MAKING ME UNAWARE OF THE SITUATION UNTIL THE CTLR CAME ON THE RADIO. WE FURTHER DISCUSSED THE IMPORTANCE OF CRM. IN HINDSIGHT; ALTHOUGH WE WERE WELL OUT ON THE APCH AND THE FO WAS SENIOR WITH 2500 HRS IN TYPE; I WILL STRIVE TO ENSURE THAT CHKLISTS ARE COMPLETED SOONER TO ALLOW ME TO BE IN A POS TO FULLY MONITOR THE ACTIONS OF THE FO ANYWHERE NEAR THE ARPT. SUPPLEMENTAL INFO FROM ACN 676715: INBOUND TO DFW; APCH TOLD US TO 'EXPECT RWY 17C' WITHOUT ANY MENTION OF THE TYPE OF APCH IN USE. THE CURRENT DFW ARR ATIS WAS FOR VMC (2200 FT SCATTERED). I BRIEFED A VISUAL APCH TO RWY 17C. OUR PLTS AND DFW APCH CTLRS CONDUCT SO MANY APCHS TOGETHER THAT CTLRS DON'T WORRY ABOUT US DOING WHAT THEY EXPECT; LIKE THEY WOULD A LESS FREQUENT VISITOR TO DFW. 99% OF THE TIME THIS IS NO PROB AND THE OP RUNS VERY SMOOTHLY. BUT THIS ALSO LEADS TO COMPLACENCY. THE FACT THAT RWY 17C CONSTRUCTION IS DONE AND THE ILS IS OPERATIONAL IS A CHANGE TO THE STATUS QUO. WHEN A PLT IS NOT AWARE OF SUCH A CHANGE AND IS WORKING WITH OLD ASSUMPTIONS; MISCOM BTWN THE PLTS AND ATC CAN EASILY HAPPEN. WHENEVER THERE IS A CHANGE LIKE THIS; CTLRS SHOULD USE EXTRA CARE IN THEIR COMS; MAKING SURE THAT CLRNCS ARE PROPERLY STATED AND READ BACK BY PLTS; ESPECIALLY WITH THOSE WHO FREQUENT DFW AND MAY MAKE WRONG ASSUMPTIONS.