Narrative:

While flying an medium large transport from keflavik to goose bay, I arrived at the canadian fir 45 NM north of track and 10 mins earlier than estimated. This was below nat track/no long range navigation ferry flight. Our flight plan was provided by base operations, hou. Wind and course data appeared accurate. However, they did not specify for ATC that we were not long range navigation equipped. After greenland, where both NDB's operated normally, we tracked outbnd then dead reckoned toward the fir and goose. The winds were different than forecast and #1 bearing pointer system, unknown to us, became unreliable. We dead reckoned using flight plan information and time. As we reported entering the fir goose DME locked on showing us 40 mi west of estimated position and north of track. Moncton questioned our progress and we informed them of the equipment on board and type of flight. After landing, I called the supervisor to confirm information and provide details of the flight equipment. On the next leg, after 3 hours of flight, the #1 bearing system became unreliable. Before leaving, it had ground-checked normal after resetting equipment. We based our position on previously reliable NDB's and flight plan information. An unforeseen wind change and unreliable NDB indication contributed to the navigation error. We were operating dr and unable to detect the off course position until receiving goose bay VOR at 160 DME northeast. Human performance was correct for the situation and equipment involved. All available equipment and information were used properly. The inaccurate #1 bearing system proved to be a subtle failure and was not detectable until receiving VOR signals. Future flts should consider using long range navigation equipment.

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Original NASA ASRS Text

Title: MLG FLT CREW WITH ONLY DOMESTIC NAVIGATION CAPABILITY ON FLT FROM KEFLIVEK TO GOOSE BAY ARRIVED IN MONCTON AREA 40 MILES AHEAD OF POSITION REPORTS AND NORTH OF COURSE.

Narrative: WHILE FLYING AN MLG FROM KEFLAVIK TO GOOSE BAY, I ARRIVED AT THE CANADIAN FIR 45 NM N OF TRACK AND 10 MINS EARLIER THAN ESTIMATED. THIS WAS BELOW NAT TRACK/NO LONG RANGE NAV FERRY FLT. OUR FLT PLAN WAS PROVIDED BY BASE OPS, HOU. WIND AND COURSE DATA APPEARED ACCURATE. HOWEVER, THEY DID NOT SPECIFY FOR ATC THAT WE WERE NOT LONG RANGE NAV EQUIPPED. AFTER GREENLAND, WHERE BOTH NDB'S OPERATED NORMALLY, WE TRACKED OUTBND THEN DEAD RECKONED TOWARD THE FIR AND GOOSE. THE WINDS WERE DIFFERENT THAN FORECAST AND #1 BEARING POINTER SYS, UNKNOWN TO US, BECAME UNRELIABLE. WE DEAD RECKONED USING FLT PLAN INFO AND TIME. AS WE RPTED ENTERING THE FIR GOOSE DME LOCKED ON SHOWING US 40 MI W OF ESTIMATED POS AND N OF TRACK. MONCTON QUESTIONED OUR PROGRESS AND WE INFORMED THEM OF THE EQUIP ON BOARD AND TYPE OF FLT. AFTER LNDG, I CALLED THE SUPVR TO CONFIRM INFO AND PROVIDE DETAILS OF THE FLT EQUIP. ON THE NEXT LEG, AFTER 3 HRS OF FLT, THE #1 BEARING SYS BECAME UNRELIABLE. BEFORE LEAVING, IT HAD GND-CHKED NORMAL AFTER RESETTING EQUIP. WE BASED OUR POS ON PREVIOUSLY RELIABLE NDB'S AND FLT PLAN INFO. AN UNFORESEEN WIND CHANGE AND UNRELIABLE NDB INDICATION CONTRIBUTED TO THE NAV ERROR. WE WERE OPERATING DR AND UNABLE TO DETECT THE OFF COURSE POS UNTIL RECEIVING GOOSE BAY VOR AT 160 DME NE. HUMAN PERFORMANCE WAS CORRECT FOR THE SITUATION AND EQUIP INVOLVED. ALL AVAILABLE EQUIP AND INFO WERE USED PROPERLY. THE INACCURATE #1 BEARING SYS PROVED TO BE A SUBTLE FAILURE AND WAS NOT DETECTABLE UNTIL RECEIVING VOR SIGNALS. FUTURE FLTS SHOULD CONSIDER USING LONG RANGE NAV EQUIP.

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.