Narrative:

While flying a turbine commander from ind to vay on an IFR flight, I forgot that approach (mcguire) had not actually given me clearance for the approach. The WX at the time was ceiling 2200 ft and 7 mi. I was cleared direct to rbv VOR and the 236 degree radial outbound, maintain 2000 ft. The 236 degree radial is the final approach course and is 'nopt.' at 16.3 DME (the FAF) I was visual but too close to the clouds above to be legal VFR, so I began descent as depicted on the approach chart. Approach called to verify my altitude and informed me that I was only cleared down to 2000 ft. At that time I was at 1200 ft so I canceled IFR and apologized for my error. I am still puzzled as to why approach had not issued approach clearance before arrival at the FAF. The following day, making the same flight, I had to request approach clearance on final. I will seek advice on this. In retrospect, I feel my biggest error was not seeking approach clearance well before the high cockpit workload point of FAF on a non precision approach. My trying to shoot a coupled approach following GPS guidance while confirming the indications with VOR exacerbated this event. Since I was visual with the ground, I thought this would be good practice. I will seek additional dedicated training on this unit.

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Original NASA ASRS Text

Title: AN SMT PLT, ON APCH TO WRI, DSNDED BELOW ASSIGNED ALT.

Narrative: WHILE FLYING A TURBINE COMMANDER FROM IND TO VAY ON AN IFR FLT, I FORGOT THAT APCH (MCGUIRE) HAD NOT ACTUALLY GIVEN ME CLRNC FOR THE APCH. THE WX AT THE TIME WAS CEILING 2200 FT AND 7 MI. I WAS CLRED DIRECT TO RBV VOR AND THE 236 DEG RADIAL OUTBOUND, MAINTAIN 2000 FT. THE 236 DEG RADIAL IS THE FINAL APCH COURSE AND IS 'NOPT.' AT 16.3 DME (THE FAF) I WAS VISUAL BUT TOO CLOSE TO THE CLOUDS ABOVE TO BE LEGAL VFR, SO I BEGAN DSCNT AS DEPICTED ON THE APCH CHART. APCH CALLED TO VERIFY MY ALT AND INFORMED ME THAT I WAS ONLY CLRED DOWN TO 2000 FT. AT THAT TIME I WAS AT 1200 FT SO I CANCELED IFR AND APOLOGIZED FOR MY ERROR. I AM STILL PUZZLED AS TO WHY APCH HAD NOT ISSUED APCH CLRNC BEFORE ARR AT THE FAF. THE FOLLOWING DAY, MAKING THE SAME FLT, I HAD TO REQUEST APCH CLRNC ON FINAL. I WILL SEEK ADVICE ON THIS. IN RETROSPECT, I FEEL MY BIGGEST ERROR WAS NOT SEEKING APCH CLRNC WELL BEFORE THE HIGH COCKPIT WORKLOAD POINT OF FAF ON A NON PRECISION APCH. MY TRYING TO SHOOT A COUPLED APCH FOLLOWING GPS GUIDANCE WHILE CONFIRMING THE INDICATIONS WITH VOR EXACERBATED THIS EVENT. SINCE I WAS VISUAL WITH THE GND, I THOUGHT THIS WOULD BE GOOD PRACTICE. I WILL SEEK ADDITIONAL DEDICATED TRAINING ON THIS UNIT.

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.