PRIMARY ELECTRICAL PWR SUPPLY PROB.

Narrative

WHILE PERFORMING TOUCH AND GO LNDGS IN L TFC; RWY 6; AT ISP; ON THE TKOF LEG; I NOTICED AND REALIZED THAT I WAS HEARING NO RADIO COMS. I SPOKE TO THE STUDENT THROUGH THE ACFT'S INTERCOM; WHICH WAS ALSO NOT WORKING. I THEN REALIZED THAT ALL RADIO LIGHTS WERE OFF AND NOTHING ELECTRICAL WAS WORKING. THE AMMETER WAS READING DISCHARGE. THIS WAS A COMPLETE AND SUDDEN FAILURE. WHILE THE STUDENT CONTINUED TO FLY THE ACFT; I ACCOMPLISHED THE CHKLIST FOR ELECTRICAL FAILURE; INCLUDING TRYING TO RESET THE ALTERNATOR. ALL ELECTRICAL EQUIP WAS SHUT OFF AND THE STUDENT WAS INSTRUCTED TO FLY THE TFC PATTERN AT TFC PATTERN ALT; AND WATCH FOR OTHER TFC. REMAINING AT TFC PATTERN ALT; I WATCHED FOR VISUAL SIGNALS FROM THE TWR. THE STUDENT PERFORMED THE ELECTRICAL FAILURE CHKLIST AGAIN AND ONE COM RADIO LIGHTS APPEARED ON; ALTHOUGH VERY DIM. I CALLED TO THE TWR IN THE BLIND TELLING HIM WE HAD AN ELECTRICAL FAILURE AND WOULD LIKE TO LAND. THE TWR CLRED US TO LAND; WHICH WAS ACKNOWLEDGE; ALTHOUGH IT WAS NOT KNOWN IF WE WERE RECEIVED. THE LNDG WAS UNEVENTFUL. AFTER SHUTDOWN; EXAMINATION OF THE ALTERNATOR BELT APPEARED SATISFACTORY. NO SMOKE OR ODORS WERE OBSERVED IN THE COWLING; COCKPIT; OR NEAR THE BATTERY. THE ACFT WAS LATER FERRIED TO FRG ARPT AFTER RECEIVING AN AUX JUMP START; AND TURNED OVER TO THE OPERATOR FOR MAINT. CONVERSATIONS WITH THE CTLRS AT ISP TWR INDICATED THAT THIS INCIDENT CAUSED NO PROBS. THEY; IN MY OPINION; HANDLED THE SIT VERY PROFESSIONALLY. AT THIS TIME; I DO NOT KNOW THE RESULTS OF THE MAINT FINDINGS. THANK YOU. THIS IS A GREAT PROGRAM.