Narrative:

While flying an ILS approach to runway 35 at mht. The following incident took place. As the PNF at the time, I had just acknowledged approach control's instructions to descend to 3000' and intercept localizer inbound. Since our pass briefing system was intermittent. I informed the first officer (PF) that I would be off the frequency. While giving the briefing I heard the first officer's transmitter clicking, which meant he was talking to approach control. During this time the first officer had been descending from 4000' to 3000', but stopped at 3300' then climbed 3500' then continued descending. At this time we were established on the localizer and G/south. When I returned to the frequency we were descending through 2700' and still established on the ILS. To me it seemed logical that we had been cleared for the approach since we were about 3-4 mi from greni (FAF fan marker that is about 1.1 mi west of the VOR that was the DME). Not willing to assume anything, I twice asked the first officer if we had been cleared for the approach he assured me both times that we had been. As we were descending through 2400' approach control asked why we were not at our assigned altitude 3000'. We regained altitude to 3000' promptly, which gave us full deflection on the G/south. We were then cleared for the approach west/O incident. During this time I did hear approach control speaking to another aircraft whether we were ever in conflict with this aircraft I do not know. After parking at the gate I questioned my first officer as to what was said while I was off the frequency. First officer informed me that approach control had requested he climb back to 3500' due traffic. They then gave instructions as follows: 'descend to 3000' maintain 3000' until established on the localizer cleared for the approach.' whether this was said I do not know. I have to take the word of the first officer until I heard the approach control tapes. Obviously being PIC it is my job to know what's going on at all times. I understand and accept that fact. In fairness to the first officer, he had shown good judgement and flying ability during the day before this incident. Callback conversation with reporter revealed the following: the reporter called and said FAA was proposing action against him. The first officer thought they had been cleared for the approach and descended out of assigned altitude. Approach control had traffic below them outbnd on the localizer course.

Related reports:

Google
 

Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION FROM ACFT Y. PLT DEVIATION.

Narrative: WHILE FLYING AN ILS APCH TO RWY 35 AT MHT. THE FOLLOWING INCIDENT TOOK PLACE. AS THE PNF AT THE TIME, I HAD JUST ACKNOWLEDGED APCH CTL'S INSTRUCTIONS TO DSND TO 3000' AND INTERCEPT LOC INBND. SINCE OUR PASS BRIEFING SYS WAS INTERMITTENT. I INFORMED THE F/O (PF) THAT I WOULD BE OFF THE FREQ. WHILE GIVING THE BRIEFING I HEARD THE F/O'S XMITTER CLICKING, WHICH MEANT HE WAS TALKING TO APCH CTL. DURING THIS TIME THE F/O HAD BEEN DSNDING FROM 4000' TO 3000', BUT STOPPED AT 3300' THEN CLBED 3500' THEN CONTINUED DSNDING. AT THIS TIME WE WERE ESTABLISHED ON THE LOC AND G/S. WHEN I RETURNED TO THE FREQ WE WERE DSNDING THROUGH 2700' AND STILL ESTABLISHED ON THE ILS. TO ME IT SEEMED LOGICAL THAT WE HAD BEEN CLRED FOR THE APCH SINCE WE WERE ABOUT 3-4 MI FROM GRENI (FAF FAN MARKER THAT IS ABOUT 1.1 MI W OF THE VOR THAT WAS THE DME). NOT WILLING TO ASSUME ANYTHING, I TWICE ASKED THE F/O IF WE HAD BEEN CLRED FOR THE APCH HE ASSURED ME BOTH TIMES THAT WE HAD BEEN. AS WE WERE DSNDING THROUGH 2400' APCH CTL ASKED WHY WE WERE NOT AT OUR ASSIGNED ALT 3000'. WE REGAINED ALT TO 3000' PROMPTLY, WHICH GAVE US FULL DEFLECTION ON THE G/S. WE WERE THEN CLRED FOR THE APCH W/O INCIDENT. DURING THIS TIME I DID HEAR APCH CTL SPEAKING TO ANOTHER ACFT WHETHER WE WERE EVER IN CONFLICT WITH THIS ACFT I DO NOT KNOW. AFTER PARKING AT THE GATE I QUESTIONED MY F/O AS TO WHAT WAS SAID WHILE I WAS OFF THE FREQ. F/O INFORMED ME THAT APCH CTL HAD REQUESTED HE CLB BACK TO 3500' DUE TFC. THEY THEN GAVE INSTRUCTIONS AS FOLLOWS: 'DSND TO 3000' MAINTAIN 3000' UNTIL ESTABLISHED ON THE LOC CLRED FOR THE APCH.' WHETHER THIS WAS SAID I DO NOT KNOW. I HAVE TO TAKE THE WORD OF THE F/O UNTIL I HEARD THE APCH CTL TAPES. OBVIOUSLY BEING PIC IT IS MY JOB TO KNOW WHAT'S GOING ON AT ALL TIMES. I UNDERSTAND AND ACCEPT THAT FACT. IN FAIRNESS TO THE F/O, HE HAD SHOWN GOOD JUDGEMENT AND FLYING ABILITY DURING THE DAY BEFORE THIS INCIDENT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: THE RPTR CALLED AND SAID FAA WAS PROPOSING ACTION AGAINST HIM. THE F/O THOUGHT THEY HAD BEEN CLRED FOR THE APCH AND DSNDED OUT OF ASSIGNED ALT. APCH CTL HAD TFC BELOW THEM OUTBND ON THE LOC COURSE.

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.