Narrative:

I was cleared for the approach to the ogm (ontonagon, mi) airport (NDB) and was approximately 8 mi to the southwest (coming from ironwood, mi apart) and cleared over to CTAF at 3500 ft MSL. When I arrived over the airport/NDB I saw the runway and decided to descend to land in what I would rate as contact approach type conditions, probably 2 mi visibility and maintaining clear of clouds. This was accomplished by circling over the runway while descending. The approach and landing was a normal event for a circling approach. The WX at the time prior to let down consisted of snow squalls with cloud tops around 4500 ft MSL and broken. Ground contact came and went prior to arriving at the NDB to do the full approach, and I was thinking I may be able to do a contact approach but did not go back to center frequency to see if I could get a contact approach clearance. Center originally cleared me for a VOR approach at the airport but I read back 'cleared for the NDB approach' as there is not a VOR approach procedure for this airport. After hearing this it was a little confusing, I thought, on the controller's part for not knowing what approachs were available at that airport. Another factor for not returning to center frequency and requesting a contact approach was from previous trips to the area knowing radio reception wasn't good at altitudes of 3500 ft and lower, and deciding I had adequate cloud clearance and visibility to perform a contact approach and would cancel IFR clearance over telephone. After reviewing AC 61-27C instrument flying handbook page 215, I concluded that I should have done the full approach to the airport regardless of the better flight conditions I encountered having not got amended clearance from ATC for a contact approach. I don't believe there was any other air traffic in my area.

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Original NASA ASRS Text

Title: SMT PLT MAKES UNAUTHORIZED CONTACT APCH IN LESS THAN VISUAL CONDITIONS TO A NON TWR ARPT.

Narrative: I WAS CLRED FOR THE APCH TO THE OGM (ONTONAGON, MI) ARPT (NDB) AND WAS APPROX 8 MI TO THE SW (COMING FROM IRONWOOD, MI APART) AND CLRED OVER TO CTAF AT 3500 FT MSL. WHEN I ARRIVED OVER THE ARPT/NDB I SAW THE RWY AND DECIDED TO DSND TO LAND IN WHAT I WOULD RATE AS CONTACT APCH TYPE CONDITIONS, PROBABLY 2 MI VISIBILITY AND MAINTAINING CLR OF CLOUDS. THIS WAS ACCOMPLISHED BY CIRCLING OVER THE RWY WHILE DSNDING. THE APCH AND LNDG WAS A NORMAL EVENT FOR A CIRCLING APCH. THE WX AT THE TIME PRIOR TO LET DOWN CONSISTED OF SNOW SQUALLS WITH CLOUD TOPS AROUND 4500 FT MSL AND BROKEN. GND CONTACT CAME AND WENT PRIOR TO ARRIVING AT THE NDB TO DO THE FULL APCH, AND I WAS THINKING I MAY BE ABLE TO DO A CONTACT APCH BUT DID NOT GO BACK TO CTR FREQ TO SEE IF I COULD GET A CONTACT APCH CLRNC. CTR ORIGINALLY CLRED ME FOR A VOR APCH AT THE ARPT BUT I READ BACK 'CLRED FOR THE NDB APCH' AS THERE IS NOT A VOR APCH PROC FOR THIS ARPT. AFTER HEARING THIS IT WAS A LITTLE CONFUSING, I THOUGHT, ON THE CTLR'S PART FOR NOT KNOWING WHAT APCHS WERE AVAILABLE AT THAT ARPT. ANOTHER FACTOR FOR NOT RETURNING TO CTR FREQ AND REQUESTING A CONTACT APCH WAS FROM PREVIOUS TRIPS TO THE AREA KNOWING RADIO RECEPTION WASN'T GOOD AT ALTS OF 3500 FT AND LOWER, AND DECIDING I HAD ADEQUATE CLOUD CLRNC AND VISIBILITY TO PERFORM A CONTACT APCH AND WOULD CANCEL IFR CLRNC OVER TELEPHONE. AFTER REVIEWING AC 61-27C INST FLYING HANDBOOK PAGE 215, I CONCLUDED THAT I SHOULD HAVE DONE THE FULL APCH TO THE ARPT REGARDLESS OF THE BETTER FLT CONDITIONS I ENCOUNTERED HAVING NOT GOT AMENDED CLRNC FROM ATC FOR A CONTACT APCH. I DON'T BELIEVE THERE WAS ANY OTHER AIR TFC IN MY AREA.

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.