Narrative:

During a day VFR traffic watch flight; experienced an alternator failure in flight while in charlie airspace.the reporter's radio pack started acting up and transmission was weak; like it wasn't getting enough power. The aircraft radios and electrical were fine up until we turned back to land early. Signs of electrical failure started to become apparent; so I told approach that we were going to lose radios. After a couple unreadable transmissions on my end; approach got the message and shipped me to tower. I checked on with tower and let them know my situation. I shed excess electrical load which really only consisted GPS/comm 1; lights; and reporter's radio pack. I squawked 7600 and brought out my handheld radio and attempted to establish communication on that; but was unable. At this point; comm 2 failed so I shut it off. I entered downwind for runway 28R and received a steady green light gun signal and acknowledged by rocking my wings. I didn't attempt to add flaps until I knew landing was assured; so that I wouldn't get stuck with flaps down in a go-around situation. When adding flaps on final they stopped at the first notch. Upon touchdown the flaps came down all the way and the ammeter indicated a charge; suspect faulty connection somewhere. Received a flashing green light from tower and taxied to the ramp. I called tower after we parked and they said no further contact was necessary. The ammeters in some of the planes we fly are not sufficient. It acts as if it's stuck and only varies slightly when turning the alternator on/off. A request has been put in with the company to fix this unacknowledged issue once and for all.

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Original NASA ASRS Text

Title: A C172 Traffic Watch Pilot reported the loss of electrical; so he squawked 7600; returned to his departure airport. The pilot was given light signals to land and taxi to parking.

Narrative: During a day VFR Traffic Watch flight; experienced an alternator failure in flight while in Charlie airspace.The Reporter's radio pack started acting up and transmission was weak; like it wasn't getting enough power. The aircraft radios and electrical were fine up until we turned back to land early. Signs of electrical failure started to become apparent; so I told Approach that we were going to lose radios. After a couple unreadable transmissions on my end; Approach got the message and shipped me to Tower. I checked on with Tower and let them know my situation. I shed excess electrical load which really only consisted GPS/COMM 1; lights; and Reporter's radio pack. I squawked 7600 and brought out my handheld radio and attempted to establish communication on that; but was unable. At this point; COMM 2 failed so I shut it off. I entered downwind for Runway 28R and received a steady green light gun signal and acknowledged by rocking my wings. I didn't attempt to add flaps until I knew landing was assured; so that I wouldn't get stuck with flaps down in a go-around situation. When adding flaps on final they stopped at the first notch. Upon touchdown the flaps came down all the way and the ammeter indicated a charge; suspect faulty connection somewhere. Received a flashing green light from Tower and taxied to the ramp. I called Tower after we parked and they said no further contact was necessary. The ammeters in some of the planes we fly are not sufficient. It acts as if it's stuck and only varies slightly when turning the alternator on/off. A request has been put in with the company to fix this unacknowledged issue once and for all.

Data retrieved from NASA's ASRS site as of July 2013 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.