C172 pilots have electrical failure en route to their destination.

Attributes
ACN	568321
Time
Date	200212
Day	Thu
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : gmu.airport
State Reference	SC
Altitude	msl single value : 5000
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : gsp.tracon tower : gmu.tower
Operator	general aviation : instructional
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Navigation In Use	ils localizer only : 244
Flight Phase	cruise : level descent : approach
Route In Use	approach : instrument non precision approach : visual
Flight Plan	IFR
Person 1
Affiliation	other
Function	flight crew : single pilot instruction : trainee
Qualification	pilot : private
Experience	flight time last 90 days : 36 flight time total : 160 flight time type : 130
ASRS Report	568321
Person 2
Affiliation	other
Function	instruction : instructor
Events
Anomaly	aircraft equipment problem : critical inflight encounter : weather other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : ammeter other flight crewa other flight crewb
Resolutory Action	none taken : anomaly accepted
Consequence	other
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Aircraft

Narrative:

While cruising en route from mcn to gmu, we experienced electrical failure. We were under an IFR flight plan. The first thing we noticed was a discharging ammeter. After troubleshooting, we were not certain if the electrical system was discharging or not. For instance, the low voltage light was not on. Shortly after noting the ammeter (5 mins) we lost intercom and had to remove headsets. At this point, we began to realize that we indeed did have a discharging electrical system. At this point it would have been wise to declare an emergency. We did not, perhaps due to confusion and continuing to troubleshoot. Perhaps 2-3 mins after intercom was lost, we lost our ability to transmit voice. Cockpit and instrument lighting also went out. At this point, we immediately went to back-up flashlights and battery pwred, hand-held GPS. We set the squawk to 7600, hit the 'identify' button, and shut off remaining equipment. We then used the GPS and flashlight and mechanical flight instruments to fly the aircraft to gmu. Upon 10 mi from gmu, we turned on #2 navigation/communication, and could barely receive the localizer signal. We shot the localizer with GPS back-up to localizer minimums (385 ft AGL). Upon reaching MDA, I was able to see the runway. We landed visually and immediately called the FAA to confirm we were on the ground, and safe. It took both myself and my instructor, at the limit of our abilities, to safely execute. I will not fly IMC without back-up, battery pwred navigation/communication equipment ever again.

Original NASA ASRS Text

Title: C172 PLTS HAVE ELECTRICAL FAILURE ENRTE TO THEIR DEST.

Narrative: WHILE CRUISING ENRTE FROM MCN TO GMU, WE EXPERIENCED ELECTRICAL FAILURE. WE WERE UNDER AN IFR FLT PLAN. THE FIRST THING WE NOTICED WAS A DISCHARGING AMMETER. AFTER TROUBLESHOOTING, WE WERE NOT CERTAIN IF THE ELECTRICAL SYS WAS DISCHARGING OR NOT. FOR INSTANCE, THE LOW VOLTAGE LIGHT WAS NOT ON. SHORTLY AFTER NOTING THE AMMETER (5 MINS) WE LOST INTERCOM AND HAD TO REMOVE HEADSETS. AT THIS POINT, WE BEGAN TO REALIZE THAT WE INDEED DID HAVE A DISCHARGING ELECTRICAL SYS. AT THIS POINT IT WOULD HAVE BEEN WISE TO DECLARE AN EMER. WE DID NOT, PERHAPS DUE TO CONFUSION AND CONTINUING TO TROUBLESHOOT. PERHAPS 2-3 MINS AFTER INTERCOM WAS LOST, WE LOST OUR ABILITY TO XMIT VOICE. COCKPIT AND INST LIGHTING ALSO WENT OUT. AT THIS POINT, WE IMMEDIATELY WENT TO BACK-UP FLASHLIGHTS AND BATTERY PWRED, HAND-HELD GPS. WE SET THE SQUAWK TO 7600, HIT THE 'IDENT' BUTTON, AND SHUT OFF REMAINING EQUIP. WE THEN USED THE GPS AND FLASHLIGHT AND MECHANICAL FLT INSTS TO FLY THE ACFT TO GMU. UPON 10 MI FROM GMU, WE TURNED ON #2 NAV/COM, AND COULD BARELY RECEIVE THE LOC SIGNAL. WE SHOT THE LOC WITH GPS BACK-UP TO LOC MINIMUMS (385 FT AGL). UPON REACHING MDA, I WAS ABLE TO SEE THE RWY. WE LANDED VISUALLY AND IMMEDIATELY CALLED THE FAA TO CONFIRM WE WERE ON THE GND, AND SAFE. IT TOOK BOTH MYSELF AND MY INSTRUCTOR, AT THE LIMIT OF OUR ABILITIES, TO SAFELY EXECUTE. I WILL NOT FLY IMC WITHOUT BACK-UP, BATTERY PWRED NAV/COM EQUIP EVER AGAIN.

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.