Narrative:

We were cleared to bravo NDB locator OM and cleared for the approach (localizer back course to runway 30 at ymh). The controller expected a full approach. The problem is that we proceeded inbound to the airport after passing bravo NDB. I will list here the circumstances that led up to this. We could not identify bravo NDB marker and were receiving a bad signal. We told approach control about this and we requested vectors for the approach. He told us to maintain our present heading for the marker. Although we were RNAV equipped, we were unable to get our GPS to accept bravo NDB. As we progressed, we became unsure if the heading we were on was to the marker for the full approach, or a vector for a straight in. Before we were able to clear this up and identify bravo NDB by another means, we got an apparent course reversal on the marker and the localizer came in. At the same time we were handed over to tower. We broke out of the clouds and got the runway in sight. We contacted tower and told him we were marker inbound with the airport in sight, hoping to be cleared for a visual since we were still not sure if they expected the full approach. He gave us a right 360 degrees before continuing inbound to allow an airport vehicle to clear the runway. All of this happened very fast and there was confusion. Having the airport in sight, I felt the appropriate thing to do was to proceed inbound. In retrospect I know I should have made myself more clear as to my intentions or simply canceled IFR before proceeding inbound. However, the cause of the situation in the first place was the inability to identify bravo NDB, the controller's vague instructions, in that we did not know for sure the purpose of the heading to bravo NDB, our failure to clear our doubt, and the pace at which all of this happened.

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Original NASA ASRS Text

Title: CARGO MLG REQUESTS VECTORS ON LOC BACK COURSE APCH WHEN UNABLE TO IDENT THE MARKER.

Narrative: WE WERE CLRED TO BRAVO NDB LOCATOR OM AND CLRED FOR THE APCH (LOC BACK COURSE TO RWY 30 AT YMH). THE CTLR EXPECTED A FULL APCH. THE PROB IS THAT WE PROCEEDED INBOUND TO THE ARPT AFTER PASSING BRAVO NDB. I WILL LIST HERE THE CIRCUMSTANCES THAT LED UP TO THIS. WE COULD NOT IDENT BRAVO NDB MARKER AND WERE RECEIVING A BAD SIGNAL. WE TOLD APCH CTL ABOUT THIS AND WE REQUESTED VECTORS FOR THE APCH. HE TOLD US TO MAINTAIN OUR PRESENT HEADING FOR THE MARKER. ALTHOUGH WE WERE RNAV EQUIPPED, WE WERE UNABLE TO GET OUR GPS TO ACCEPT BRAVO NDB. AS WE PROGRESSED, WE BECAME UNSURE IF THE HEADING WE WERE ON WAS TO THE MARKER FOR THE FULL APCH, OR A VECTOR FOR A STRAIGHT IN. BEFORE WE WERE ABLE TO CLR THIS UP AND IDENT BRAVO NDB BY ANOTHER MEANS, WE GOT AN APPARENT COURSE REVERSAL ON THE MARKER AND THE LOC CAME IN. AT THE SAME TIME WE WERE HANDED OVER TO TWR. WE BROKE OUT OF THE CLOUDS AND GOT THE RWY IN SIGHT. WE CONTACTED TWR AND TOLD HIM WE WERE MARKER INBOUND WITH THE ARPT IN SIGHT, HOPING TO BE CLRED FOR A VISUAL SINCE WE WERE STILL NOT SURE IF THEY EXPECTED THE FULL APCH. HE GAVE US A R 360 DEGS BEFORE CONTINUING INBOUND TO ALLOW AN ARPT VEHICLE TO CLR THE RWY. ALL OF THIS HAPPENED VERY FAST AND THERE WAS CONFUSION. HAVING THE ARPT IN SIGHT, I FELT THE APPROPRIATE THING TO DO WAS TO PROCEED INBOUND. IN RETROSPECT I KNOW I SHOULD HAVE MADE MYSELF MORE CLR AS TO MY INTENTIONS OR SIMPLY CANCELED IFR BEFORE PROCEEDING INBOUND. HOWEVER, THE CAUSE OF THE SIT IN THE FIRST PLACE WAS THE INABILITY TO IDENT BRAVO NDB, THE CTLR'S VAGUE INSTRUCTIONS, IN THAT WE DID NOT KNOW FOR SURE THE PURPOSE OF THE HEADING TO BRAVO NDB, OUR FAILURE TO CLR OUR DOUBT, AND THE PACE AT WHICH ALL OF THIS HAPPENED.

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.