Narrative:

When my instrument student and I went out to start the small aircraft, we found the battery dead. We had line service being an APU and proceeded with a normal start using external power. After departure, we proceeded to pelham intersection, then down V415 towards TOC on our training flight. I remembered during climb out I forgot to bring my flashlight. Stupid mistake. While we were about 20 NM from TOC I switched off the alternator to see if the battery was recharged (before doing this I noted the load meter showed only normal load for the equipment being used). I was not surprised when the electrical power was lost after the altimeter was turned off; however I was surprised to find that the alternator would not come back on line! Since we were in VMC, and knew our precise position, I elected to proceed to 7a1 an ex-USAF base, which is uncontrolled and has 8000' of runway. Luckily the pilot controled lighting was already activated and no traffic in the area. After setting up normal approach speed I reminded my student not to add any back pressure until we could make out the skid marks on the runway. A normal T/D followed. Just as the mains touched, the runway lights went out. We rolled out and searched for the taxiway in the dark. In finding the taxiway we caught a taxiway light with the left wheel pant. In the future, on night flts, I will make extra sure that I have an operating flashlight and my portable transceiver on board the aircraft.

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Original NASA ASRS Text

Title: GA SMA LOST ELECTRICAL POWER INFLT WHEN INSTRUCTOR PLT TURNED OFF THE ALTERNATOR TO CHECK BATTERY CHARGE. BATTERY WAS DEAD BEFORE ENGINE START.

Narrative: WHEN MY INSTRUMENT STUDENT AND I WENT OUT TO START THE SMA, WE FOUND THE BATTERY DEAD. WE HAD LINE SVC BEING AN APU AND PROCEEDED WITH A NORMAL START USING EXTERNAL PWR. AFTER DEP, WE PROCEEDED TO PELHAM INTXN, THEN DOWN V415 TOWARDS TOC ON OUR TRNING FLT. I REMEMBERED DURING CLBOUT I FORGOT TO BRING MY FLASHLIGHT. STUPID MISTAKE. WHILE WE WERE ABOUT 20 NM FROM TOC I SWITCHED OFF THE ALTERNATOR TO SEE IF THE BATTERY WAS RECHARGED (BEFORE DOING THIS I NOTED THE LOAD METER SHOWED ONLY NORMAL LOAD FOR THE EQUIP BEING USED). I WAS NOT SURPRISED WHEN THE ELECTRICAL PWR WAS LOST AFTER THE ALTIMETER WAS TURNED OFF; HOWEVER I WAS SURPRISED TO FIND THAT THE ALTERNATOR WOULD NOT COME BACK ON LINE! SINCE WE WERE IN VMC, AND KNEW OUR PRECISE POS, I ELECTED TO PROCEED TO 7A1 AN EX-USAF BASE, WHICH IS UNCTLED AND HAS 8000' OF RWY. LUCKILY THE PLT CTLED LIGHTING WAS ALREADY ACTIVATED AND NO TFC IN THE AREA. AFTER SETTING UP NORMAL APCH SPD I REMINDED MY STUDENT NOT TO ADD ANY BACK PRESSURE UNTIL WE COULD MAKE OUT THE SKID MARKS ON THE RWY. A NORMAL T/D FOLLOWED. JUST AS THE MAINS TOUCHED, THE RWY LIGHTS WENT OUT. WE ROLLED OUT AND SEARCHED FOR THE TXWY IN THE DARK. IN FINDING THE TXWY WE CAUGHT A TXWY LIGHT WITH THE LEFT WHEEL PANT. IN THE FUTURE, ON NIGHT FLTS, I WILL MAKE EXTRA SURE THAT I HAVE AN OPERATING FLASHLIGHT AND MY PORTABLE TRANSCEIVER ON BOARD THE ACFT.

Data retrieved from NASA's ASRS site as of August 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.