Narrative:

On nov/xa/00, I was returning from savannah, GA, to clt, nc, home base for my airplane. I had taken my daughter and a friend of hers to savannah that day to visit a college. I was on an IFR flight plan, though conditions were VMC. My altitude, per my flight plan, was 5000 ft MSL. At approximately XA20 (dusk, after sunset and close to night) after being handed off to clt approach control by columbia approach control, I was told by clt to expect a visual approach to runway 36L in clt, but I made a request for runway 36R. The original clt approach controller noted my request, then handed me off to another frequency and approach controller. The new controller gave me a heading of 30 degrees and instructed me to descend to 3600 ft and to intercept the localizer for runway 36R. I acknowledged the instruction, turned to 30 degrees and began my descent at a rate of approximately 700 FPM. During the approach, my front seat passenger appeared a bit apprehensive, looking for the airport and not being able to see it yet. I attempted to explain a little about what I was doing as I commenced the approach into clt, and also tried to generally point out the direction of and distance to the airport. As I was talking with the passenger, I intercepted the localizer and turned to a heading of 003 degrees, continuing my descent. When I finished talking and completing my turn, I checked my altitude again and realized I had descended to 2900 ft, below my assigned altitude of 3600 ft. I immediately climbed back to 3600 ft, and continued the approach. A couple of mins later the controller gave me an instruction to descend to 2300 ft, and I acknowledged the instruction and descended to 2300 ft. The controller did not mention my altitude deviation at any time. When I called the airport in sight about 4 mi out, I was cleared for the visual approach, contacted the tower per the approach controller's instruction, and was cleared to land on runway 36R. The rest of the approach and landing (which by then was a night landing) was uneventful.

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Original NASA ASRS Text

Title: PLT OF A PIPER ARCHER, PA28, DSNDED BELOW ASSIGNED ALT DURING INTERCEPTING THE LOC.

Narrative: ON NOV/XA/00, I WAS RETURNING FROM SAVANNAH, GA, TO CLT, NC, HOME BASE FOR MY AIRPLANE. I HAD TAKEN MY DAUGHTER AND A FRIEND OF HERS TO SAVANNAH THAT DAY TO VISIT A COLLEGE. I WAS ON AN IFR FLT PLAN, THOUGH CONDITIONS WERE VMC. MY ALT, PER MY FLT PLAN, WAS 5000 FT MSL. AT APPROX XA20 (DUSK, AFTER SUNSET AND CLOSE TO NIGHT) AFTER BEING HANDED OFF TO CLT APCH CTL BY COLUMBIA APCH CTL, I WAS TOLD BY CLT TO EXPECT A VISUAL APCH TO RWY 36L IN CLT, BUT I MADE A REQUEST FOR RWY 36R. THE ORIGINAL CLT APCH CTLR NOTED MY REQUEST, THEN HANDED ME OFF TO ANOTHER FREQ AND APCH CTLR. THE NEW CTLR GAVE ME A HDG OF 30 DEGS AND INSTRUCTED ME TO DSND TO 3600 FT AND TO INTERCEPT THE LOC FOR RWY 36R. I ACKNOWLEDGED THE INSTRUCTION, TURNED TO 30 DEGS AND BEGAN MY DSCNT AT A RATE OF APPROX 700 FPM. DURING THE APCH, MY FRONT SEAT PAX APPEARED A BIT APPREHENSIVE, LOOKING FOR THE ARPT AND NOT BEING ABLE TO SEE IT YET. I ATTEMPTED TO EXPLAIN A LITTLE ABOUT WHAT I WAS DOING AS I COMMENCED THE APCH INTO CLT, AND ALSO TRIED TO GENERALLY POINT OUT THE DIRECTION OF AND DISTANCE TO THE ARPT. AS I WAS TALKING WITH THE PAX, I INTERCEPTED THE LOC AND TURNED TO A HDG OF 003 DEGS, CONTINUING MY DSCNT. WHEN I FINISHED TALKING AND COMPLETING MY TURN, I CHKED MY ALT AGAIN AND REALIZED I HAD DSNDED TO 2900 FT, BELOW MY ASSIGNED ALT OF 3600 FT. I IMMEDIATELY CLBED BACK TO 3600 FT, AND CONTINUED THE APCH. A COUPLE OF MINS LATER THE CTLR GAVE ME AN INSTRUCTION TO DSND TO 2300 FT, AND I ACKNOWLEDGED THE INSTRUCTION AND DSNDED TO 2300 FT. THE CTLR DID NOT MENTION MY ALTDEV AT ANY TIME. WHEN I CALLED THE ARPT IN SIGHT ABOUT 4 MI OUT, I WAS CLRED FOR THE VISUAL APCH, CONTACTED THE TWR PER THE APCH CTLR'S INSTRUCTION, AND WAS CLRED TO LAND ON RWY 36R. THE REST OF THE APCH AND LNDG (WHICH BY THEN WAS A NIGHT LNDG) WAS UNEVENTFUL.

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.