Narrative:

We were on our second approach attempt after missing the first attempt with ground contact but no airport in sight. Upon receiving our final vector to intercept the approach course we were instructed to 'maintain 2000' until established...' I believe I heard, '...and cleared for the NDB 6 approach.' since we received this vector as we were already intercepting I began my descent as we had on the previous attempt which was given at the same distance from the beacon (7 mi). The initial published altitude is 1900'. Upon passing through 1600' the controller repeated, 'company identification maintain 2000' until established cleared for the NDB 6 approach.' we acknowledged and continued the approach. It was a difficult approach requiring strong correction for wind and turbulence. I wanted to get established and descend out of the wind as soon as practical. I queried my first officer asking, 'weren't we already cleared for the approach?' he responded he didn't believe so and didn't remember reading back the approach clearance, yet he allowed me to descend west/O question. As far as contributing factors go, it is a familiar approach, one I shoot regularly. The vectors were the same as on the previous attempt. So, it all seemed so similar and either my first officer was not paying attention or felt intimidated to speak up. I still believe I heard an approach clearance, but perhaps that was just 'wishful hearing.' certain reflection and constant attention is required to each word and instruction even in familiar situations.

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Original NASA ASRS Text

Title: COMMUTER SMT NON ADHERENCE TO ATC CLRNC. STARTED DESCENT BEFORE ESTABLISHED ON IAP NDB APCH.

Narrative: WE WERE ON OUR SECOND APCH ATTEMPT AFTER MISSING THE FIRST ATTEMPT WITH GND CONTACT BUT NO ARPT IN SIGHT. UPON RECEIVING OUR FINAL VECTOR TO INTERCEPT THE APCH COURSE WE WERE INSTRUCTED TO 'MAINTAIN 2000' UNTIL ESTABLISHED...' I BELIEVE I HEARD, '...AND CLRED FOR THE NDB 6 APCH.' SINCE WE RECEIVED THIS VECTOR AS WE WERE ALREADY INTERCEPTING I BEGAN MY DSCNT AS WE HAD ON THE PREVIOUS ATTEMPT WHICH WAS GIVEN AT THE SAME DISTANCE FROM THE BEACON (7 MI). THE INITIAL PUBLISHED ALT IS 1900'. UPON PASSING THROUGH 1600' THE CTLR REPEATED, 'COMPANY ID MAINTAIN 2000' UNTIL ESTABLISHED CLRED FOR THE NDB 6 APCH.' WE ACKNOWLEDGED AND CONTINUED THE APCH. IT WAS A DIFFICULT APCH REQUIRING STRONG CORRECTION FOR WIND AND TURB. I WANTED TO GET ESTABLISHED AND DSND OUT OF THE WIND AS SOON AS PRACTICAL. I QUERIED MY F/O ASKING, 'WEREN'T WE ALREADY CLRED FOR THE APCH?' HE RESPONDED HE DIDN'T BELIEVE SO AND DIDN'T REMEMBER READING BACK THE APCH CLRNC, YET HE ALLOWED ME TO DSND W/O QUESTION. AS FAR AS CONTRIBUTING FACTORS GO, IT IS A FAMILIAR APCH, ONE I SHOOT REGULARLY. THE VECTORS WERE THE SAME AS ON THE PREVIOUS ATTEMPT. SO, IT ALL SEEMED SO SIMILAR AND EITHER MY F/O WAS NOT PAYING ATTN OR FELT INTIMIDATED TO SPEAK UP. I STILL BELIEVE I HEARD AN APCH CLRNC, BUT PERHAPS THAT WAS JUST 'WISHFUL HEARING.' CERTAIN REFLECTION AND CONSTANT ATTN IS REQUIRED TO EACH WORD AND INSTRUCTION EVEN IN FAMILIAR SITUATIONS.

Data retrieved from NASA's ASRS site as of August 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.