Narrative:

I was alone in the aircraft intending to remain in the pattern and perform touch and goes. The airport is an uncontrolled field with unicom. Upon turning downwind at 1000 ft AGL I activated the radio talk switch to announce the downwind leg. The radio was dead. Looking at the radio led's, they were all dark. 2 way communication was thus lost. I checked the circuit breaker panel, running my finger along all the breakers, but none were tripped. I extended the downwind leg and jiggled the audio panel switches and buttons without success. I believe I tripped the rocker switches, including the master, to see if I could restore electrical power. The radios remained dark. I made the decision to proceed to a full stop landing, since the radios were not working. I activated the landing gear 'wheel' but no green lights came on. I concluded the electrical failure extended to the green landing gear lights. Without radio communication, I could not ask for a fly-by to check if the gear was extended. I set up for a long final, thinking that if the gear switch was not working, as it was electrical, the piper automatic gear extension fail-safe system would lower the gear as long as I ensured slow enough airspeed. I did not know if the green lights were on the same circuit as the switch. I crossed the threshold and bled off as much airspeed as I could so that the automatic extension system would operate. I also wanted to land as slowly and level as possible in case the gear was not deployed. The aircraft landed wheels up with virtually no perceptible impact, dead level. The screeching sound of scraping metal was quite loud as the plane skidded down the centerline in a straight direction, turning slightly as it came to rest perhaps 5 or 6 seconds later. There was a strong burning smell, likely activated by friction. I opened the exit door as field personnel ran up, yelling at me to get out of the plane. I tried to make sure all switches were off before exiting. There was no further damage or ensuing fire. I believe there are two worthwhile conclusions to be drawn from this experience. First, I was under the impression that while the green gear lights were electrical, the gear mechanism was a combination of gravity and hydraulics, which, if not tripped by the cockpit switch, would work with piper's overriding gear sensing system. This system lowers the gear if airspeed/power combinations are below certain minimums. I have checked with 2 other piper pilots, each with several hundred hours in type and both of whom owned retractable single engine pipers, and both thought the piper sensing system would lower the gear following an electrical failure. This conclusion is incorrect. I can state that with 38 hours in type, of which 9 hours were dual instructional hours in 1997, I was not familiar with piper's emergency extension system located between the front seats, and use of that system did not occur to me during this incident. Subsequent reading of a lance poh reveals the emergency system does not depend on electrical power. When I spoke to the other 2 piper owners mentioned above, they were only vaguely aware of this system and one believed there was a crank located between the seats, which is not the case. Both pilots have stated their knowledge was insufficient and they probably would have acted in the same manner as I did. Secondly, the chain of events was significant in that the problem first manifested itself in the radios, rather than the landing gear. As a result, my chain of thinking followed the chain of discovered events. I tended to localize the problem in the cockpit panel, rather than the entire aircraft. If the first indication of a problem had been no green lights upon activation of the landing gear handle, it is possible I would have used the emergency gear extension handle, although, as stated above, I do not recall any significant training in this area and certainly never activated this during training. In light of all the factors noted above, I tentatively conclude the incident may have been avoidable with better training on the 3 piper landing gear deployment system. Since I was not alone in my lack of thorough knowledge of the system, it may be appropriate for all piper retractable pilots to become more proficient with these system, and specifically familiar with which are rendered inoperable due to electrical failure. This should include actual hands-on training.

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Original NASA ASRS Text

Title: PA28R NOTED LOSS OF COM. LATER REALIZED HAD LOST ELECTRICAL SYS. ELECTED TO RETURN FIELD AND ASSUMED THE GEAR WOULD AUTOMATICALLY DEPLOY WITH PIPER AUTOMATIC GEAR EXTENSION FEATURE. LANDED GEAR UP, MINOR DAMAGE TO THE ACFT. NO FIRE OR INJURIES. FEELS INADEQUATELY TRAINED.

Narrative: I WAS ALONE IN THE ACFT INTENDING TO REMAIN IN THE PATTERN AND PERFORM TOUCH AND GOES. THE ARPT IS AN UNCTLED FIELD WITH UNICOM. UPON TURNING DOWNWIND AT 1000 FT AGL I ACTIVATED THE RADIO TALK SWITCH TO ANNOUNCE THE DOWNWIND LEG. THE RADIO WAS DEAD. LOOKING AT THE RADIO LED'S, THEY WERE ALL DARK. 2 WAY COM WAS THUS LOST. I CHKED THE CIRCUIT BREAKER PANEL, RUNNING MY FINGER ALONG ALL THE BREAKERS, BUT NONE WERE TRIPPED. I EXTENDED THE DOWNWIND LEG AND JIGGLED THE AUDIO PANEL SWITCHES AND BUTTONS WITHOUT SUCCESS. I BELIEVE I TRIPPED THE ROCKER SWITCHES, INCLUDING THE MASTER, TO SEE IF I COULD RESTORE ELECTRICAL PWR. THE RADIOS REMAINED DARK. I MADE THE DECISION TO PROCEED TO A FULL STOP LNDG, SINCE THE RADIOS WERE NOT WORKING. I ACTIVATED THE LNDG GEAR 'WHEEL' BUT NO GREEN LIGHTS CAME ON. I CONCLUDED THE ELECTRICAL FAILURE EXTENDED TO THE GREEN LNDG GEAR LIGHTS. WITHOUT RADIO COM, I COULD NOT ASK FOR A FLY-BY TO CHK IF THE GEAR WAS EXTENDED. I SET UP FOR A LONG FINAL, THINKING THAT IF THE GEAR SWITCH WAS NOT WORKING, AS IT WAS ELECTRICAL, THE PIPER AUTOMATIC GEAR EXTENSION FAIL-SAFE SYS WOULD LOWER THE GEAR AS LONG AS I ENSURED SLOW ENOUGH AIRSPD. I DID NOT KNOW IF THE GREEN LIGHTS WERE ON THE SAME CIRCUIT AS THE SWITCH. I CROSSED THE THRESHOLD AND BLED OFF AS MUCH AIRSPD AS I COULD SO THAT THE AUTOMATIC EXTENSION SYS WOULD OPERATE. I ALSO WANTED TO LAND AS SLOWLY AND LEVEL AS POSSIBLE IN CASE THE GEAR WAS NOT DEPLOYED. THE ACFT LANDED WHEELS UP WITH VIRTUALLY NO PERCEPTIBLE IMPACT, DEAD LEVEL. THE SCREECHING SOUND OF SCRAPING METAL WAS QUITE LOUD AS THE PLANE SKIDDED DOWN THE CTRLINE IN A STRAIGHT DIRECTION, TURNING SLIGHTLY AS IT CAME TO REST PERHAPS 5 OR 6 SECONDS LATER. THERE WAS A STRONG BURNING SMELL, LIKELY ACTIVATED BY FRICTION. I OPENED THE EXIT DOOR AS FIELD PERSONNEL RAN UP, YELLING AT ME TO GET OUT OF THE PLANE. I TRIED TO MAKE SURE ALL SWITCHES WERE OFF BEFORE EXITING. THERE WAS NO FURTHER DAMAGE OR ENSUING FIRE. I BELIEVE THERE ARE TWO WORTHWHILE CONCLUSIONS TO BE DRAWN FROM THIS EXPERIENCE. FIRST, I WAS UNDER THE IMPRESSION THAT WHILE THE GREEN GEAR LIGHTS WERE ELECTRICAL, THE GEAR MECHANISM WAS A COMBINATION OF GRAVITY AND HYDS, WHICH, IF NOT TRIPPED BY THE COCKPIT SWITCH, WOULD WORK WITH PIPER'S OVERRIDING GEAR SENSING SYS. THIS SYS LOWERS THE GEAR IF AIRSPD/PWR COMBINATIONS ARE BELOW CERTAIN MINIMUMS. I HAVE CHKED WITH 2 OTHER PIPER PLTS, EACH WITH SEVERAL HUNDRED HRS IN TYPE AND BOTH OF WHOM OWNED RETRACTABLE SINGLE ENG PIPERS, AND BOTH THOUGHT THE PIPER SENSING SYS WOULD LOWER THE GEAR FOLLOWING AN ELECTRICAL FAILURE. THIS CONCLUSION IS INCORRECT. I CAN STATE THAT WITH 38 HRS IN TYPE, OF WHICH 9 HRS WERE DUAL INSTRUCTIONAL HRS IN 1997, I WAS NOT FAMILIAR WITH PIPER'S EMER EXTENSION SYS LOCATED BTWN THE FRONT SEATS, AND USE OF THAT SYS DID NOT OCCUR TO ME DURING THIS INCIDENT. SUBSEQUENT READING OF A LANCE POH REVEALS THE EMER SYS DOES NOT DEPEND ON ELECTRICAL PWR. WHEN I SPOKE TO THE OTHER 2 PIPER OWNERS MENTIONED ABOVE, THEY WERE ONLY VAGUELY AWARE OF THIS SYS AND ONE BELIEVED THERE WAS A CRANK LOCATED BTWN THE SEATS, WHICH IS NOT THE CASE. BOTH PLTS HAVE STATED THEIR KNOWLEDGE WAS INSUFFICIENT AND THEY PROBABLY WOULD HAVE ACTED IN THE SAME MANNER AS I DID. SECONDLY, THE CHAIN OF EVENTS WAS SIGNIFICANT IN THAT THE PROB FIRST MANIFESTED ITSELF IN THE RADIOS, RATHER THAN THE LNDG GEAR. AS A RESULT, MY CHAIN OF THINKING FOLLOWED THE CHAIN OF DISCOVERED EVENTS. I TENDED TO LOCALIZE THE PROB IN THE COCKPIT PANEL, RATHER THAN THE ENTIRE ACFT. IF THE FIRST INDICATION OF A PROB HAD BEEN NO GREEN LIGHTS UPON ACTIVATION OF THE LNDG GEAR HANDLE, IT IS POSSIBLE I WOULD HAVE USED THE EMER GEAR EXTENSION HANDLE, ALTHOUGH, AS STATED ABOVE, I DO NOT RECALL ANY SIGNIFICANT TRAINING IN THIS AREA AND CERTAINLY NEVER ACTIVATED THIS DURING TRAINING. IN LIGHT OF ALL THE FACTORS NOTED ABOVE, I TENTATIVELY CONCLUDE THE INCIDENT MAY HAVE BEEN AVOIDABLE WITH BETTER TRAINING ON THE 3 PIPER LNDG GEAR DEPLOYMENT SYS. SINCE I WAS NOT ALONE IN MY LACK OF THOROUGH KNOWLEDGE OF THE SYS, IT MAY BE APPROPRIATE FOR ALL PIPER RETRACTABLE PLTS TO BECOME MORE PROFICIENT WITH THESE SYS, AND SPECIFICALLY FAMILIAR WITH WHICH ARE RENDERED INOPERABLE DUE TO ELECTRICAL FAILURE. THIS SHOULD INCLUDE ACTUAL HANDS-ON TRAINING.

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.