Narrative:

Flying a cessna 172A. I departed mdh at XA25 pm. Upon departure I noticed a constant, but slight, static coming over the radios. I stayed in the traffic pattern for a series of 4 touch and goes then proceeded to exit the traffic pattern. Upon exiting the traffic pattern I climbed to an altitude 1700 ft MSL and headed south. At XB15 pm I reached the carbondale city limits. At this time the static had not diminished but had got louder. The sound annoyed my passenger so I decided to try to remedy the problem. I turned my position lights, beacon, and transponder off and then finally turned the master switch off. I had left the electrical system off for less than a min then turned it back on. The static had diminished a little so I decided to repeat the process. While trying to fix the static, I flew over the southeast corner of the city, descended to 1000 ft AGL, and turned to an east heading. I made a turn from east to north and then after a couple mins turned to a heading of west. The static persisted so I decided to check the fuses to see if any of them were damaged or blown. I let the control yoke go because I believed the aircraft to be trimmed for level flight and then proceeded to check the fuses. I checked each fuse looking up at my altitude often then after I checked the last fuse I noticed the aircraft was losing altitude. I applied full power to the engine and then started a positive rate of climb. The lowest I had gone was 1200 ft MSL and I never came closer than 1/2 mi to the nearest standing obstacle. I then decided to leave carbondale.

Google
 

Original NASA ASRS Text

Title: DURING A NIGHT SIGHT SEEING FLT A PVT PLT DSNDED BELOW THE MINIMUM SAFE ALT FOR OVER CONGESTED AREAS.

Narrative: FLYING A CESSNA 172A. I DEPARTED MDH AT XA25 PM. UPON DEP I NOTICED A CONSTANT, BUT SLIGHT, STATIC COMING OVER THE RADIOS. I STAYED IN THE TFC PATTERN FOR A SERIES OF 4 TOUCH AND GOES THEN PROCEEDED TO EXIT THE TFC PATTERN. UPON EXITING THE TFC PATTERN I CLBED TO AN ALT 1700 FT MSL AND HEADED S. AT XB15 PM I REACHED THE CARBONDALE CITY LIMITS. AT THIS TIME THE STATIC HAD NOT DIMINISHED BUT HAD GOT LOUDER. THE SOUND ANNOYED MY PAX SO I DECIDED TO TRY TO REMEDY THE PROB. I TURNED MY POS LIGHTS, BEACON, AND XPONDER OFF AND THEN FINALLY TURNED THE MASTER SWITCH OFF. I HAD LEFT THE ELECTRICAL SYS OFF FOR LESS THAN A MIN THEN TURNED IT BACK ON. THE STATIC HAD DIMINISHED A LITTLE SO I DECIDED TO REPEAT THE PROCESS. WHILE TRYING TO FIX THE STATIC, I FLEW OVER THE SE CORNER OF THE CITY, DSNDED TO 1000 FT AGL, AND TURNED TO AN E HDG. I MADE A TURN FROM E TO N AND THEN AFTER A COUPLE MINS TURNED TO A HDG OF W. THE STATIC PERSISTED SO I DECIDED TO CHK THE FUSES TO SEE IF ANY OF THEM WERE DAMAGED OR BLOWN. I LET THE CTL YOKE GO BECAUSE I BELIEVED THE ACFT TO BE TRIMMED FOR LEVEL FLT AND THEN PROCEEDED TO CHK THE FUSES. I CHKED EACH FUSE LOOKING UP AT MY ALT OFTEN THEN AFTER I CHKED THE LAST FUSE I NOTICED THE ACFT WAS LOSING ALT. I APPLIED FULL PWR TO THE ENG AND THEN STARTED A POSITIVE RATE OF CLB. THE LOWEST I HAD GONE WAS 1200 FT MSL AND I NEVER CAME CLOSER THAN 1/2 MI TO THE NEAREST STANDING OBSTACLE. I THEN DECIDED TO LEAVE CARBONDALE.

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.