Narrative:

Just prior to initiating descent from FL370; we experienced complete loss of our EFIS system; communication and navigation radios; transponder; and various other electrical equipment. We were in VMC with variable broken to overcast clouds below; with widely scattered areas where we could see the ground. Current WX at rog was reported as VFR with a broken layer of clouds around 4000 ft. We were about 15 mins from our destination with about 1 hour 30 mins of fuel remaining. After our initial attempts to regain power to our communication and navigation radios failed; we agreed to begin our descent towards rog. At this point we were flying the airplane using only our standby attitude indicator; copilot's vsi; standby altimeter; and magnetic compass. During the descent we noticed that the #1 eadi circuit breaker had popped. Once on the ground; we discovered that it was actually the 'essential a' bus breaker (pilot's side) that had popped. There is a checklist procedure for dc bus failure that we could have completed; possibly restoring some power to the right or left 'essential a' bus; had we recognized what circuit breaker had popped and elected to reset breakers. Labeling and position of the breakers are such that the label for the breaker is below the breaker and positioned low behind the pilot's left knee (or copilot's right knee). We mistakenly read the label above the breaker. During descent; we spontaneously regained lost electrical power to EFIS; communication and navigation system for about 30 seconds. The first officer called ZKC and reported our electrical problem. Before he was able to declare an emergency; we lost communication again. After our second power loss; the first officer noted what he thought was a popped #2 ehsi circuit breaker. Again; we misread this and had actually popped the right 'essential a' bus breaker. Continuing to troubleshoot; I asked the first officer to try his backup radio switch located on the aft bottom row of the circuit breaker panel. He did and we regained use of our VOR; DME; and ADF receivers. I don't recall for sure but we may have had ADF the whole time. During descent we discussed and decided against resetting circuit breakers. We discussed using cell phones to contact FSS but by this time we were within approximately 40 NM of rog and were reasonably confident that we would be able to navigation clear of clouds using pilotage to the airport. Our focus had shifted to what system were affected that we would need for landing and considered and/or tested the availability of flaps; spoiler; landing gear and anti-skid system. During descent; clouds had forced us to maneuver south of the initial magnetic heading that we were maintaining to rog. Our first positive identify of any landmark was on top of xna which was in the clear at that time. We continued our descent northbound and east of xna through a large hole in the clouds. We discussed landing at xna but agreed to continue on to rog knowing xna was a good option if we had any trouble finding rog. We descended below the cloud deck; idented vbt and rog shortly thereafter. Since our problem was more than just communication failure we entered the pattern on a wide right base for runway 20; which we were most conveniently set up for. My assumption was that ZKC would alert razorback approach and rogers tower to our situation. On final approach to land; we received and acknowledged light gun signals from the tower. Despite what the checklists say; we are strongly encouraged in training to not reset popped breakers unless absolutely necessary. This training affects our response to electrical problems. If we had properly idented the circuit breakers that popped we would have run the appropriate checklist. However; given our situation at the time and in light of our training; we would have likely elected to not reset the circuit breakers. Our overall situational awareness would have improved but our decisions and outcomes would have remained the same.

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Original NASA ASRS Text

Title: LR35 SUFFERS COMPLETE LOSS OF NAVAID AND COM RADIOS WHILE DSNDING FROM FL370. FLT CREW FOLLOWS LOST COM PROCS TO SAFE ARR AT DEST ARPT USING LIGHT SIGNALS FOR LNDG CLRNC.

Narrative: JUST PRIOR TO INITIATING DSCNT FROM FL370; WE EXPERIENCED COMPLETE LOSS OF OUR EFIS SYS; COM AND NAV RADIOS; XPONDER; AND VARIOUS OTHER ELECTRICAL EQUIP. WE WERE IN VMC WITH VARIABLE BROKEN TO OVCST CLOUDS BELOW; WITH WIDELY SCATTERED AREAS WHERE WE COULD SEE THE GND. CURRENT WX AT ROG WAS RPTED AS VFR WITH A BROKEN LAYER OF CLOUDS AROUND 4000 FT. WE WERE ABOUT 15 MINS FROM OUR DEST WITH ABOUT 1 HR 30 MINS OF FUEL REMAINING. AFTER OUR INITIAL ATTEMPTS TO REGAIN PWR TO OUR COM AND NAV RADIOS FAILED; WE AGREED TO BEGIN OUR DSCNT TOWARDS ROG. AT THIS POINT WE WERE FLYING THE AIRPLANE USING ONLY OUR STANDBY ATTITUDE INDICATOR; COPLT'S VSI; STANDBY ALTIMETER; AND MAGNETIC COMPASS. DURING THE DSCNT WE NOTICED THAT THE #1 EADI CIRCUIT BREAKER HAD POPPED. ONCE ON THE GND; WE DISCOVERED THAT IT WAS ACTUALLY THE 'ESSENTIAL A' BUS BREAKER (PLT'S SIDE) THAT HAD POPPED. THERE IS A CHKLIST PROC FOR DC BUS FAILURE THAT WE COULD HAVE COMPLETED; POSSIBLY RESTORING SOME PWR TO THE R OR L 'ESSENTIAL A' BUS; HAD WE RECOGNIZED WHAT CIRCUIT BREAKER HAD POPPED AND ELECTED TO RESET BREAKERS. LABELING AND POS OF THE BREAKERS ARE SUCH THAT THE LABEL FOR THE BREAKER IS BELOW THE BREAKER AND POSITIONED LOW BEHIND THE PLT'S L KNEE (OR COPLT'S R KNEE). WE MISTAKENLY READ THE LABEL ABOVE THE BREAKER. DURING DSCNT; WE SPONTANEOUSLY REGAINED LOST ELECTRICAL PWR TO EFIS; COM AND NAV SYS FOR ABOUT 30 SECONDS. THE FO CALLED ZKC AND RPTED OUR ELECTRICAL PROB. BEFORE HE WAS ABLE TO DECLARE AN EMER; WE LOST COM AGAIN. AFTER OUR SECOND PWR LOSS; THE FO NOTED WHAT HE THOUGHT WAS A POPPED #2 EHSI CIRCUIT BREAKER. AGAIN; WE MISREAD THIS AND HAD ACTUALLY POPPED THE R 'ESSENTIAL A' BUS BREAKER. CONTINUING TO TROUBLESHOOT; I ASKED THE FO TO TRY HIS BACKUP RADIO SWITCH LOCATED ON THE AFT BOTTOM ROW OF THE CIRCUIT BREAKER PANEL. HE DID AND WE REGAINED USE OF OUR VOR; DME; AND ADF RECEIVERS. I DON'T RECALL FOR SURE BUT WE MAY HAVE HAD ADF THE WHOLE TIME. DURING DSCNT WE DISCUSSED AND DECIDED AGAINST RESETTING CIRCUIT BREAKERS. WE DISCUSSED USING CELL PHONES TO CONTACT FSS BUT BY THIS TIME WE WERE WITHIN APPROX 40 NM OF ROG AND WERE REASONABLY CONFIDENT THAT WE WOULD BE ABLE TO NAV CLR OF CLOUDS USING PILOTAGE TO THE ARPT. OUR FOCUS HAD SHIFTED TO WHAT SYS WERE AFFECTED THAT WE WOULD NEED FOR LNDG AND CONSIDERED AND/OR TESTED THE AVAILABILITY OF FLAPS; SPOILER; LNDG GEAR AND ANTI-SKID SYS. DURING DSCNT; CLOUDS HAD FORCED US TO MANEUVER S OF THE INITIAL MAGNETIC HDG THAT WE WERE MAINTAINING TO ROG. OUR FIRST POSITIVE IDENT OF ANY LANDMARK WAS ON TOP OF XNA WHICH WAS IN THE CLR AT THAT TIME. WE CONTINUED OUR DSCNT NBOUND AND E OF XNA THROUGH A LARGE HOLE IN THE CLOUDS. WE DISCUSSED LNDG AT XNA BUT AGREED TO CONTINUE ON TO ROG KNOWING XNA WAS A GOOD OPTION IF WE HAD ANY TROUBLE FINDING ROG. WE DSNDED BELOW THE CLOUD DECK; IDENTED VBT AND ROG SHORTLY THEREAFTER. SINCE OUR PROB WAS MORE THAN JUST COM FAILURE WE ENTERED THE PATTERN ON A WIDE R BASE FOR RWY 20; WHICH WE WERE MOST CONVENIENTLY SET UP FOR. MY ASSUMPTION WAS THAT ZKC WOULD ALERT RAZORBACK APCH AND ROGERS TWR TO OUR SITUATION. ON FINAL APCH TO LAND; WE RECEIVED AND ACKNOWLEDGED LIGHT GUN SIGNALS FROM THE TWR. DESPITE WHAT THE CHKLISTS SAY; WE ARE STRONGLY ENCOURAGED IN TRAINING TO NOT RESET POPPED BREAKERS UNLESS ABSOLUTELY NECESSARY. THIS TRAINING AFFECTS OUR RESPONSE TO ELECTRICAL PROBS. IF WE HAD PROPERLY IDENTED THE CIRCUIT BREAKERS THAT POPPED WE WOULD HAVE RUN THE APPROPRIATE CHKLIST. HOWEVER; GIVEN OUR SITUATION AT THE TIME AND IN LIGHT OF OUR TRAINING; WE WOULD HAVE LIKELY ELECTED TO NOT RESET THE CIRCUIT BREAKERS. OUR OVERALL SITUATIONAL AWARENESS WOULD HAVE IMPROVED BUT OUR DECISIONS AND OUTCOMES WOULD HAVE REMAINED THE SAME.

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.