Electrical failure and lose communication. Regained communication with emergency avionics.

Attributes
ACN	302979
Time
Date	199504
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ugn
State Reference	IL
Altitude	msl bound lower : 2000 msl bound upper : 2000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : ord tracon : bpt
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other descent : approach
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument pilot : atp
Experience	flight time last 90 days : 40 flight time total : 2900 flight time type : 35
ASRS Report	302979
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : declared emergency flight crew : overcame equipment problem other
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

On a repositioning flight from chicago-midway to waukegan, noticed immediately after takeoff that avionics were behaving poorly -- radios had much static and VOR's were intermittently losing signal. Also electric altimeter that gives signal to autoplt was jumping occasionally causing autoplt, when engaged, to make rapid altitude changes. I thus disengaged autoplt. Upon being told to expect vectors for ILS runway 23 at waukegan, I noticed that #1 navigation was no longer able to receive any signal. Since this is navigation connected to pilot's HSI, I told ATC of problem to see if alternate approach was possible. Upon being given vectors toward waukegan approach, ATC notified me they had lost transponder, they then said they could not hear me any more. Shortly thereafter, radios went completely dead and I was unable to hear or speak to ATC on either communication. I also tried tower frequency. Since I was then in visual contact with water and land, I proceeded towards airport and a attempted to lower landing gear. However the electrical failure also meant that gear indicators did not show gear was down. I circled airport and attempted to change electrical bus and restart generators, etc. I switched to emergency avionics and again was able to talk to ATC who said airport had been flashing green light to clear me to land. (I had not seen green light) but I was now able to talk and was switched to tower and had airport in sight. I was about to ask tower to check if my wheels were down when the indicators finally responded. Upon landing, nosewheel steering (electrical) was out too, so taxi was with differential braking #1 altimeter still read 2000 ft, only copilot was giving correct reading. Preliminary indication from mechanic is that both current limiters failed, first one shortly after takeoff, then second when total electrical system failed. Even with redundancy problems can occur! When avionics first started behaving strangely, I should probably have returned to mdw but waukegan seemed so close.

Original NASA ASRS Text

Title: ELECTRICAL FAILURE AND LOSE COM. REGAINED COM WITH EMER AVIONICS.

Narrative: ON A REPOSITIONING FLT FROM CHICAGO-MIDWAY TO WAUKEGAN, NOTICED IMMEDIATELY AFTER TKOF THAT AVIONICS WERE BEHAVING POORLY -- RADIOS HAD MUCH STATIC AND VOR'S WERE INTERMITTENTLY LOSING SIGNAL. ALSO ELECTRIC ALTIMETER THAT GIVES SIGNAL TO AUTOPLT WAS JUMPING OCCASIONALLY CAUSING AUTOPLT, WHEN ENGAGED, TO MAKE RAPID ALT CHANGES. I THUS DISENGAGED AUTOPLT. UPON BEING TOLD TO EXPECT VECTORS FOR ILS RWY 23 AT WAUKEGAN, I NOTICED THAT #1 NAV WAS NO LONGER ABLE TO RECEIVE ANY SIGNAL. SINCE THIS IS NAV CONNECTED TO PLT'S HSI, I TOLD ATC OF PROB TO SEE IF ALTERNATE APCH WAS POSSIBLE. UPON BEING GIVEN VECTORS TOWARD WAUKEGAN APCH, ATC NOTIFIED ME THEY HAD LOST XPONDER, THEY THEN SAID THEY COULD NOT HEAR ME ANY MORE. SHORTLY THEREAFTER, RADIOS WENT COMPLETELY DEAD AND I WAS UNABLE TO HEAR OR SPEAK TO ATC ON EITHER COM. I ALSO TRIED TWR FREQ. SINCE I WAS THEN IN VISUAL CONTACT WITH WATER AND LAND, I PROCEEDED TOWARDS ARPT AND A ATTEMPTED TO LOWER LNDG GEAR. HOWEVER THE ELECTRICAL FAILURE ALSO MEANT THAT GEAR INDICATORS DID NOT SHOW GEAR WAS DOWN. I CIRCLED ARPT AND ATTEMPTED TO CHANGE ELECTRICAL BUS AND RESTART GENERATORS, ETC. I SWITCHED TO EMER AVIONICS AND AGAIN WAS ABLE TO TALK TO ATC WHO SAID ARPT HAD BEEN FLASHING GREEN LIGHT TO CLR ME TO LAND. (I HAD NOT SEEN GREEN LIGHT) BUT I WAS NOW ABLE TO TALK AND WAS SWITCHED TO TWR AND HAD ARPT IN SIGHT. I WAS ABOUT TO ASK TWR TO CHK IF MY WHEELS WERE DOWN WHEN THE INDICATORS FINALLY RESPONDED. UPON LNDG, NOSEWHEEL STEERING (ELECTRICAL) WAS OUT TOO, SO TAXI WAS WITH DIFFERENTIAL BRAKING #1 ALTIMETER STILL READ 2000 FT, ONLY COPLT WAS GIVING CORRECT READING. PRELIMINARY INDICATION FROM MECH IS THAT BOTH CURRENT LIMITERS FAILED, FIRST ONE SHORTLY AFTER TKOF, THEN SECOND WHEN TOTAL ELECTRICAL SYS FAILED. EVEN WITH REDUNDANCY PROBS CAN OCCUR! WHEN AVIONICS FIRST STARTED BEHAVING STRANGELY, I SHOULD PROBABLY HAVE RETURNED TO MDW BUT WAUKEGAN SEEMED SO CLOSE.

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.