A C172 CFI AND STUDENT PLT LOSE THEIR COM FREQ WITH TWR AND RETURN IN THE MIDDLE OF A TSTM; LNDG WITHOUT CLRNC AT OPF; FL.

Narrative

AT THE TIME OF MY DEP THERE WERE HVY AIR MASS-TYPE RAIN SHOWERS N AND E OF THE ARPT. I DECIDED TO TAKE OFF SINCE I SAW NO LIGHTNING; THE WINDS WERE CALM; AND THERE WAS NO SIGNIFICANT WX ACTIVITY S AND W OF THE AIRFIELD. I HAD MY STUDENT FLY WBOUND TO THE LCL VFR TRAINING AREA; WHERE HE DID ABOUT 30 MINS OF PRE-SOLO AIRWORK MANEUVERS. ON THE RETURN TRIP TO THE ORIGINAL ARPT OF DEP; OUR RADIOS FAILED TO RECEIVE THE ATIS OR TWR XMISSIONS. LIKEWISE ALL THE NAV SYS APPEARED TO BE DEAD. AFTER CHKING THE OBVIOUS; NAMELY VOLUME; CORRECT FREQS; HEADSET CONNECTIONS; ETC; I NOTICED THAT THE 5 AMP INST CIRCUIT BREAKER HAD POPPED; THE FUEL GAUGES READ ZERO AND THE AMMETER WAS SHOWING A NEGATIVE VALUE. BY NOW WE WERE ABOUT 15 NM W OF OUR DEST IN VFR WX CONDITIONS. I TOLD MY STUDENT TO ORBIT AROUND A LANDMARK AT 1500 FT MSL WHILE I TRIED TO CORRECT THE PROB BY TURNING OFF ALL THE ELECTRICAL EQUIP; BATTERY AND ALTERNATOR. AFTER A COUPLE OF MINS; I RESET THE CIRCUIT BREAKER BUT IT POPPED AGAIN. I TURNED ON THE BATTERY; ALTERNATOR; ONE RADIO AND THE XPONDER (WITH A 7600 SQUAWK). AGAIN I RELAYED MY SIT ON PRIMARY TWR FREQ BUT RECEIVED NO RESPONSE. AT THIS TIME I COULD SEE A HVY RAIN SHOWER MOVING INTO THE ARPT AREA FROM THE SE; SO USING MY HAND-HELD TRANSCEIVER I RELAYED OUR SIT TO THE TWR INDICATING I WAS COMING IN FROM THE W FOR A STRAIGHT-IN APCH ON RWY 9R. ON SHORT FINAL; I HAD MY STUDENT LOOK FOR A GREEN LIGHT FROM THE TWR WHILE I LANDED THE PLANE. SHORTLY AFTER I LANDED AND CLRED THE RWY; A HVY RAIN SHOWER ENGULFED THE AREA AND THE ARPT WENT IFR. I CONTACTED THE TWR ON MY CELLULAR PHONE AND THE CTLR; AFTER CLRING ME TO TAXI TO THE RAMP; INDICATED THAT THE TWR HAD BEEN USING THE SECONDARY TWR FREQ. AFTER I PARKED I ENTERED THE ELECTRICAL MALFUNCTION IN THE AIRPLANE MAINT LOGBOOK; AND THE OWNER/A&P SAID THAT IT LOOKED LIKE A SHORT IN THE INTERCOM SYS. 1 HR LATER; I CALLED THE TWR TO DISCUSS WHAT HAD HAPPENED AND THE CTLR SAID THAT A LIGHTNING STRIKE HAD KNOCKED OUT THE PWR CAUSING THEM TO USE THE SECONDARY TWR FREQ. HE INDICATED THAT HE HAD GIVEN ME A GREEN LIGHT BUT HE COULD NOT SEE THE AIRPLANE DUE TO THE RAIN FALLING IN THE TWR AREA. HE ALSO SUGGESTED TO REFER TO THE 'FLIPS CHART' TO GET THE TWR SECONDARY FREQ IN CASE I NEEDED IT IN THE FUTURE. THE FOLLOWING DAY; AT ABOUT XA00; I WENT TO THE SAME ARPT TO FLY A TRAINING FLT AND THE FBO DISPATCHER TOLD ME A TWR CTLR HAD A CALL FOR ME. SHE SAID HE WANTED TO TALK TO ME OTHERWISE HE WAS GOING TO RPT ME TO FLT STANDARDS. I RETURNED THE CALL IMMEDIATELY; AND THE CTLR PROCEEDED TO QUESTION MY JUDGEMENT AND KNOWLEDGE FOR TAKING OFF IN POOR WX; NOT USING THE SECONDARY TWR FREQ; AND NOT CONTACTING THE LCL RADAR APCH FACILITY. HE INDICATED THAT HE HAD HEARD MY XMISSIONS AND THAT APCH CTL HAD MY 7600 SQUAWK ON RADAR. I TIRED TO EXPLAIN TO HIM THAT AN ELECTRICAL MALFUNCTION HAD AFFECTED MY RADIOS BUT TO NO AVAIL. HE ENDED BY SAYING THAT HE REALLY COULD NOT COME UP WITH ANYTHING SPECIFICALLY ILLEGAL ABOUT MY ACTIONS TO TELL FLT STANDARDS; OTHER THAN THE FACT THAT I MADE HIS BLOOD PRESSURE GO UP; SO HE WAS GOING TO LET IT PASS. I THANKED HIM FOR HIS CONCERN AND AGREED WITH HIM THAT; GIVEN SIMILAR WX CONDITIONS; I WOULD HAVE BEEN BETTER OFF REMAINING ON THE GND; AND ALSO THAT I SHOULD HAVE KNOWN ABOUT THE SECONDARY TWR FREQ. ALSO; IN RETROSPECT; I CAN'T HELP BUT WONDER: WHY WOULD A LIGHTNING STRIKE RENDER THE PRIMARY TWR FREQ UNUSABLE BUT NOT THE SECONDARY? ALSO; WOULD MY ACTIONS FALL UNDER DEFINITION OF 'CARELESS OR RECKLESS OP' AS DEFINED IN FAR 91.13? I PRESUME THE TWR CTLR WHO ADMONISHED ME MIGHT HAVE ANSWERS TO THESE QUESTIONS; BUT GIVEN HIS CAUSTIC TONE I AM NOT ABOUT TO PURSUE ANY FURTHER DISCUSSION ON THIS MATTER AT THIS TIME.