COMMUTER SMT DESCENDED TO MDA BEFORE REACHING THE FAF.

Narrative

I WAS A NEW CAPT MAKING MY THIRD TRIP AFTER COMPLETING MY IOE. THREE DAYS PRIOR TO THE TRIP OUR COMPANY HAD IMPLEMENTED A POLICY OF HAVING NEW CAPTS MAKE ALL TKOFS; LNDGS AND APCHS UNTIL THEY HAD 100 HRS OF PIC. WE HAD SPENT MOST OF THE MORNING IN IFR CONDITIONS WITH GUSTY WINDS AND LIGHT TO MODERATE TURB. THE NOTAMS STATED THE LONGEST RWY AT FSD WAS CLOSED AND BOTH THE ILS AND ALS WERE OTS. ATIS INFORMED US THAT THE VOR DME APCH WAS IN USE; SO I GAVE THE F/O AN APCH BRIEF AS PER COMPANY POLICY. WE WERE THEN RADAR VECTORED TO THE FINAL APCH COURSE. ONCE ESTABLISHED ON THE APCH AND WITHIN 15 NM OF THE FAF (THE 10 NM DME FIX) WE WERE ALLOWED TO DSND TO 2900'. IN MY MIND I PUT THE FAF AT THE 15 NM DME FIX INSTEAD OF AT THE 10 NM DME FIX. AS WE CROSSED THE 15 NM DME FIX WE DID THE FINAL CHKLIST AND DSNDED TO THE MDA AT WHICH TIME WE BROKE OUT. AT 10.7 NM THE CTLR ASKED OUR ALT WHICH THE F/O RESPONDED; 'AT OUR MINIMUMS OF 2020'.' THE CTLR THEN REPLIED THAT WE SHOULD BE AT 2900' UNTIL THE FAF. BY THAT TIME WE PASSED THE REAL FAF AND NO FURTHER ACTION WAS REQUIRED. CONTRIBUTING FACTORS WHICH LED TO THE MISTAKEN FAF INCLUDE: PLT FATIGUE DUE TO NO AUTOPLT; FLYING OVER 4 HRS IN CONTINUOUS TURB AND 4 LOW APCHS W/O A BREAK. ALSO CONTRIBUTING WAS THE F/O'S ATTITUDE. HE WAS VERY UPSET AT THE COMPANY SINCE HE HAD 2500 HRS IN THE TYPE OF ACFT AND YET WAS NOT ALLOWED TO TKOF; LAND OR DO APCHS. AS A RESULT HE FELT HIS ONLY JOB WAS TO RUN THE RADIOS AND REMOVED HIMSELF FROM THE TASK OF MONITORING THE FLYING PLT. IT IS ESSENTIAL THAT THE PF IS ABSOLUTELY POSITIVE ABOUT ALL DETAILS OF THE APCH. IT IS EQUALLY IMPORTANT THAT THE PNF MONITORS THE PROGRESS OF THE FLT. LASTLY; THE NEW COMPANY POLICY (AND NPRM) DESERVED MORE RESEARCH BEFORE IT WAS IMPLEMENTED (AND BEFORE IT BECOMES AN FAR).