Narrative:

I was giving dual instruction to a commercial multi-instrument rated pilot for his instrument proficiency check. We began the ipc with a hold over the ZZZ1 VOR. ATC reported that they lost our transponder; so we tried to cycle the transponder. After my second communication with ATC; my first radio panel began to scramble and slowly burnt out. Then shortly after the second radio panel did the same thing; and I was left with no radio and electrical functions. I then made the decision to depart class C airspace and go to ZZZ2 which was an uncontrolled airport for my landing there. Once we departed the hold; I squawked 7600 on my transponder and continued to ZZZ2. I overflew the field at 2500 ft and found that runway X was in use at ZZZ2. I turned on an extended downwind so I could see and avoid all traffic. I had no way to contact anyone to state my intentions. I then went through my descent procedures and found that I had no indications that my gear was down. I had no green; red unsafe; gear in transition lights or aural warning when throttle was reduced. I then decided to do a manual gear extension so I slowed to 60 KTS and dropped the manual gear knob. I did approximately 5-6 s-turns with extensive rudder inputs to yaw the aircraft to ensure the gear was in the locked position and also for spacing behind a C172. I was on an approximately 2 mi final. I then continued for the landing. I had no way to contact anyone on the ground or in the air to visually check my gear. While touching down I felt the gear underneath me collapse. I held the nose of the aircraft off as long as possible and shut down the airplane. I did not shut it down quickly enough to prevent engine stoppage. I then came to a complete stop on the centerline of runway X and both my student and I exited the aircraft.

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Original NASA ASRS Text

Title: INSTRUCTOR AND ADVANCED STUDENT ABOARD PA28 SUFFER COMPLETE ELECTRICAL FAILURE WHICH RESULTS IN INCOMPLETE LANDING GEAR EXTENSION AND SUBSEQUENT COLLAPSE ON LANDING.

Narrative: I WAS GIVING DUAL INSTRUCTION TO A COMMERCIAL MULTI-INST RATED PLT FOR HIS INST PROFICIENCY CHK. WE BEGAN THE IPC WITH A HOLD OVER THE ZZZ1 VOR. ATC RPTED THAT THEY LOST OUR XPONDER; SO WE TRIED TO CYCLE THE XPONDER. AFTER MY SECOND COM WITH ATC; MY FIRST RADIO PANEL BEGAN TO SCRAMBLE AND SLOWLY BURNT OUT. THEN SHORTLY AFTER THE SECOND RADIO PANEL DID THE SAME THING; AND I WAS LEFT WITH NO RADIO AND ELECTRICAL FUNCTIONS. I THEN MADE THE DECISION TO DEPART CLASS C AIRSPACE AND GO TO ZZZ2 WHICH WAS AN UNCTLED ARPT FOR MY LNDG THERE. ONCE WE DEPARTED THE HOLD; I SQUAWKED 7600 ON MY XPONDER AND CONTINUED TO ZZZ2. I OVERFLEW THE FIELD AT 2500 FT AND FOUND THAT RWY X WAS IN USE AT ZZZ2. I TURNED ON AN EXTENDED DOWNWIND SO I COULD SEE AND AVOID ALL TFC. I HAD NO WAY TO CONTACT ANYONE TO STATE MY INTENTIONS. I THEN WENT THROUGH MY DSCNT PROCS AND FOUND THAT I HAD NO INDICATIONS THAT MY GEAR WAS DOWN. I HAD NO GREEN; RED UNSAFE; GEAR IN TRANSITION LIGHTS OR AURAL WARNING WHEN THROTTLE WAS REDUCED. I THEN DECIDED TO DO A MANUAL GEAR EXTENSION SO I SLOWED TO 60 KTS AND DROPPED THE MANUAL GEAR KNOB. I DID APPROX 5-6 S-TURNS WITH EXTENSIVE RUDDER INPUTS TO YAW THE ACFT TO ENSURE THE GEAR WAS IN THE LOCKED POS AND ALSO FOR SPACING BEHIND A C172. I WAS ON AN APPROX 2 MI FINAL. I THEN CONTINUED FOR THE LNDG. I HAD NO WAY TO CONTACT ANYONE ON THE GND OR IN THE AIR TO VISUALLY CHK MY GEAR. WHILE TOUCHING DOWN I FELT THE GEAR UNDERNEATH ME COLLAPSE. I HELD THE NOSE OF THE ACFT OFF AS LONG AS POSSIBLE AND SHUT DOWN THE AIRPLANE. I DID NOT SHUT IT DOWN QUICKLY ENOUGH TO PREVENT ENG STOPPAGE. I THEN CAME TO A COMPLETE STOP ON THE CTRLINE OF RWY X AND BOTH MY STUDENT AND I EXITED THE ACFT.

Data retrieved from NASA's ASRS site as of January 2009 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.