Narrative:

WX--departure and climb = VFR (VMC). Return and descent = scattered (IMC) IFR. Abeam cager intersection on climb en route to cod on V4, #1 navigation failed. Self-test of unit made with navigation tuned to den (117.0). Response was (VOR unusable--low 30 HZ reference signal). Navigation then tested on gll (112.8) and cys (113.1) with similar self-test results. #1 navigation circuit breaker pulled and reset with no change. Navigation identifier monitored throughout all tests. No aural signal received. MEL consulted. Navigation could not be deferred with flight into existing and forecast WX conditions at cod and riw. Company dispatch office contacted to see if they agreed with my MEL interpretation and that return was necessary. It was agreed that return was in order. Clearance for return to denver was requested and received. As aircraft turned toward den, right bleed air fail warning light illuminated (melted or ruptured right bleed air failure warning line). Right bleed air valve set to 'instrument/envir' off. Engine instruments monitored. No abnormal readings observed. Company dispatch office advised of right bleed air fail warning light. Dispatch office advised to take the aircraft to the hangar upon arrival in denver. Upon hand off to denver approach control and at the time of the initial radar vectoring turn, aural identify signals for den VOR were received on the inoperative navigation. Operation checks on both navigation and ILS/localizer frequencies confirmed normal operation. Suspecting a transient electrical fault of some type, the right bleed switch was recycled to open. The warning light remained off. Company dispatch office was contacted and advised that fault conditions had corrected themselves and should flight be continued to cod or returned to den? We were advised to standby. As vector was received for final approach to runway 26R at den, company dispatch office was again contacted for recommended decision. When it was once again clarified that all aircraft system had returned to normal, continued flight to cod was recommended. Clearance through denver was requested of denver tower. No landing being required, radar vectors were received out of the den TCA and on course to cod. The balance of the day's flts were completed with no recurrence of the problems. Since there was no den landing and no recurrence of the problems, no aircraft logbook entries were made.

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Original NASA ASRS Text

Title: COMMUTER SMT ON FRY LOST CAPT'S NAV RADIO AND STARTED RETURN LAND WHEN ACFT EQUIPMENT PROBLEM RESOLVED ITSELF. FLT CONTINUED TO ORIGINAL DESTINATION.

Narrative: WX--DEP AND CLB = VFR (VMC). RETURN AND DSCNT = SCATTERED (IMC) IFR. ABEAM CAGER INTXN ON CLB ENRTE TO COD ON V4, #1 NAV FAILED. SELF-TEST OF UNIT MADE WITH NAV TUNED TO DEN (117.0). RESPONSE WAS (VOR UNUSABLE--LOW 30 HZ REF SIGNAL). NAV THEN TESTED ON GLL (112.8) AND CYS (113.1) WITH SIMILAR SELF-TEST RESULTS. #1 NAV CB PULLED AND RESET WITH NO CHANGE. NAV IDENTIFIER MONITORED THROUGHOUT ALL TESTS. NO AURAL SIGNAL RECEIVED. MEL CONSULTED. NAV COULD NOT BE DEFERRED WITH FLT INTO EXISTING AND FORECAST WX CONDITIONS AT COD AND RIW. COMPANY DISPATCH OFFICE CONTACTED TO SEE IF THEY AGREED WITH MY MEL INTERP AND THAT RETURN WAS NECESSARY. IT WAS AGREED THAT RETURN WAS IN ORDER. CLRNC FOR RETURN TO DENVER WAS REQUESTED AND RECEIVED. AS ACFT TURNED TOWARD DEN, R BLEED AIR FAIL WARNING LIGHT ILLUMINATED (MELTED OR RUPTURED RIGHT BLEED AIR FAILURE WARNING LINE). RIGHT BLEED AIR VALVE SET TO 'INST/ENVIR' OFF. ENG INSTS MONITORED. NO ABNORMAL READINGS OBSERVED. COMPANY DISPATCH OFFICE ADVISED OF R BLEED AIR FAIL WARNING LIGHT. DISPATCH OFFICE ADVISED TO TAKE THE ACFT TO THE HANGAR UPON ARR IN DENVER. UPON HAND OFF TO DENVER APCH CTL AND AT THE TIME OF THE INITIAL RADAR VECTORING TURN, AURAL IDENT SIGNALS FOR DEN VOR WERE RECEIVED ON THE INOPERATIVE NAV. OPERATION CHECKS ON BOTH NAV AND ILS/LOC FREQUENCIES CONFIRMED NORMAL OPERATION. SUSPECTING A TRANSIENT ELECTRICAL FAULT OF SOME TYPE, THE RIGHT BLEED SWITCH WAS RECYCLED TO OPEN. THE WARNING LIGHT REMAINED OFF. COMPANY DISPATCH OFFICE WAS CONTACTED AND ADVISED THAT FAULT CONDITIONS HAD CORRECTED THEMSELVES AND SHOULD FLT BE CONTINUED TO COD OR RETURNED TO DEN? WE WERE ADVISED TO STANDBY. AS VECTOR WAS RECEIVED FOR FINAL APCH TO RWY 26R AT DEN, COMPANY DISPATCH OFFICE WAS AGAIN CONTACTED FOR RECOMMENDED DECISION. WHEN IT WAS ONCE AGAIN CLARIFIED THAT ALL ACFT SYS HAD RETURNED TO NORMAL, CONTINUED FLT TO COD WAS RECOMMENDED. CLRNC THROUGH DENVER WAS REQUESTED OF DENVER TWR. NO LANDING BEING REQUIRED, RADAR VECTORS WERE RECEIVED OUT OF THE DEN TCA AND ON COURSE TO COD. THE BAL OF THE DAY'S FLTS WERE COMPLETED WITH NO RECURRENCE OF THE PROBS. SINCE THERE WAS NO DEN LANDING AND NO RECURRENCE OF THE PROBS, NO ACFT LOGBOOK ENTRIES WERE MADE.

Data retrieved from NASA's ASRS site as of August 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.