Narrative:

Our scheduled airline flight from anc ak to sea wa departed anc at XA03Z with all communications on our number 1 VHF communication radio ground 121.9, tower 118.3. We departed anc runway 32 with clearance for an anc 9 SID. Cleared to 14000 ft. Transponder code XXXX. After takeoff changed to anc departure control on 118.6 on SID heading of 300 at approximately XA05Z departure gave left turn heading 260 at approximately XA07Z left turn to 110 proceed direct to middleton island when receiving. At approximately XA10Z change to anchorage center 119.7 anchorage center answered on the second call by us with fly heading 095 radar vector sandspit B.C. Climb to and maintain FL330. At approximately XA15Z change to 133.6. We reached top of climb FL330 at XA20Z. At approximately XA50Z anchorage center called changing us to 126.6 with no change in the vector heading 095 they were very hard to read but this is normal in this location abeam of yakutat ak. We heard no more conversation with center and were not concerned by a considerable quiet period with this being a saturday and much less activity on the radios being quite normal in this area on the weekends. At approximately XB15Z we attempted to call anchorage center on 126.6 on our #1 radio, no answer. VOR on sandspit B.C. Came in at 200 DME and showed us way left of the direct track to it. We changed to our # 2 VHF and called anchorage center we heard them answer by holding the squelch button. They advised us radar contact lost 50 northwest of level island change to 118.5. We were then cleared direct to annette island VOR maintain FL330. We had to hold a 35 degree right crab to hold the right to the annette VOR. Anc center advised us that they had been trying to call us on every available frequency including 121.5 and company H.F. We monitor ATC frequencys on our number 1 VHF at all times and company frequency in that area 120.9 on our # 2 VHF. We don't have any H.F. Radios. We had heard no calls on either of these for this period of silence however periods of 30 to 40 minutes along this routing happens often. Many times aircraft in this area have to relay to other aircraft for center because of location. I have been flying over this routing for over 30 years, and our system is very improved over what it used to be however I think we need more remote relays to eliminate the dead communication areas that we have. Anc center instructed us to contact vancouver center over annette VOR on 128.0. We attempted this with our # 1 VHF and could not understand their response they were strength 5 but only 1 on clarity. We switched to our # 2 VHF and they were 5x5. We completed the flight using our #2 VHF for all our ATC communications. All normal, arrived at sea at XD02Z. Anc center always has done a fine professional job and we appreciate this. The gulf of alaska always has been an area in which communications can become a problem at any time. I think that more remotes, better located remotes, or direct satellite will have to be our answer. We find the situation we were involved in to be very embarrassing and concerning to say the least. We will be a lot more cognizant of any quiet periods in the future and will initiate calls sooner. We were on top of a solid overcast at FL330 and would have recognized a problem sooner if we could have seen any recognizable land area along the coast. We are not certain if the problem was the intermittent condition of our # 1 VHF receiver or the remotes or both. We have a tendency to think that the problem was our # 1 VHF. It was written up in the maintenance log as intermittent by us.

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Original NASA ASRS Text

Title: LOST COM ACCOUNT INTERMITTENT VHF RECEIVER.

Narrative: OUR SCHEDULED AIRLINE FLT FROM ANC AK TO SEA WA DEPARTED ANC AT XA03Z WITH ALL COMS ON OUR NUMBER 1 VHF COM RADIO GND 121.9, TWR 118.3. WE DEPARTED ANC RWY 32 WITH CLRNC FOR AN ANC 9 SID. CLRED TO 14000 FT. XPONDER CODE XXXX. AFTER TKOF CHANGED TO ANC DEP CTL ON 118.6 ON SID HDG OF 300 AT APPROX XA05Z DEP GAVE L TURN HDG 260 AT APPROX XA07Z L TURN TO 110 PROCEED DIRECT TO MIDDLETON ISLAND WHEN RECEIVING. AT APPROX XA10Z CHANGE TO ANCHORAGE CTR 119.7 ANCHORAGE CTR ANSWERED ON THE SECOND CALL BY US WITH FLY HDG 095 RADAR VECTOR SANDSPIT B.C. CLB TO AND MAINTAIN FL330. AT APPROX XA15Z CHANGE TO 133.6. WE REACHED TOP OF CLB FL330 AT XA20Z. AT APPROX XA50Z ANCHORAGE CTR CALLED CHANGING US TO 126.6 WITH NO CHANGE IN THE VECTOR HDG 095 THEY WERE VERY HARD TO READ BUT THIS IS NORMAL IN THIS LOCATION ABEAM OF YAKUTAT AK. WE HEARD NO MORE CONVERSATION WITH CTR AND WERE NOT CONCERNED BY A CONSIDERABLE QUIET PERIOD WITH THIS BEING A SATURDAY AND MUCH LESS ACTIVITY ON THE RADIOS BEING QUITE NORMAL IN THIS AREA ON THE WEEKENDS. AT APPROX XB15Z WE ATTEMPTED TO CALL ANCHORAGE CTR ON 126.6 ON OUR #1 RADIO, NO ANSWER. VOR ON SANDSPIT B.C. CAME IN AT 200 DME AND SHOWED US WAY L OF THE DIRECT TRACK TO IT. WE CHANGED TO OUR # 2 VHF AND CALLED ANCHORAGE CTR WE HEARD THEM ANSWER BY HOLDING THE SQUELCH BUTTON. THEY ADVISED US RADAR CONTACT LOST 50 NW OF LEVEL ISLAND CHANGE TO 118.5. WE WERE THEN CLRED DIRECT TO ANNETTE ISLAND VOR MAINTAIN FL330. WE HAD TO HOLD A 35 DEG R CRAB TO HOLD THE R TO THE ANNETTE VOR. ANC CTR ADVISED US THAT THEY HAD BEEN TRYING TO CALL US ON EVERY AVAILABLE FREQ INCLUDING 121.5 AND COMPANY H.F. WE MONITOR ATC FREQS ON OUR NUMBER 1 VHF AT ALL TIMES AND COMPANY FREQ IN THAT AREA 120.9 ON OUR # 2 VHF. WE DON'T HAVE ANY H.F. RADIOS. WE HAD HEARD NO CALLS ON EITHER OF THESE FOR THIS PERIOD OF SILENCE HOWEVER PERIODS OF 30 TO 40 MINUTES ALONG THIS ROUTING HAPPENS OFTEN. MANY TIMES ACFT IN THIS AREA HAVE TO RELAY TO OTHER ACFT FOR CTR BECAUSE OF LOCATION. I HAVE BEEN FLYING OVER THIS ROUTING FOR OVER 30 YEARS, AND OUR SYS IS VERY IMPROVED OVER WHAT IT USED TO BE HOWEVER I THINK WE NEED MORE REMOTE RELAYS TO ELIMINATE THE DEAD COM AREAS THAT WE HAVE. ANC CTR INSTRUCTED US TO CONTACT VANCOUVER CTR OVER ANNETTE VOR ON 128.0. WE ATTEMPTED THIS WITH OUR # 1 VHF AND COULD NOT UNDERSTAND THEIR RESPONSE THEY WERE STRENGTH 5 BUT ONLY 1 ON CLARITY. WE SWITCHED TO OUR # 2 VHF AND THEY WERE 5X5. WE COMPLETED THE FLT USING OUR #2 VHF FOR ALL OUR ATC COMS. ALL NORMAL, ARRIVED AT SEA AT XD02Z. ANC CTR ALWAYS HAS DONE A FINE PROFESSIONAL JOB AND WE APPRECIATE THIS. THE GULF OF ALASKA ALWAYS HAS BEEN AN AREA IN WHICH COMS CAN BECOME A PROB AT ANY TIME. I THINK THAT MORE REMOTES, BETTER LOCATED REMOTES, OR DIRECT SATELLITE WILL HAVE TO BE OUR ANSWER. WE FIND THE SIT WE WERE INVOLVED IN TO BE VERY EMBARRASSING AND CONCERNING TO SAY THE LEAST. WE WILL BE A LOT MORE COGNIZANT OF ANY QUIET PERIODS IN THE FUTURE AND WILL INITIATE CALLS SOONER. WE WERE ON TOP OF A SOLID OVERCAST AT FL330 AND WOULD HAVE RECOGNIZED A PROB SOONER IF WE COULD HAVE SEEN ANY RECOGNIZABLE LAND AREA ALONG THE COAST. WE ARE NOT CERTAIN IF THE PROB WAS THE INTERMITTENT CONDITION OF OUR # 1 VHF RECEIVER OR THE REMOTES OR BOTH. WE HAVE A TENDENCY TO THINK THAT THE PROB WAS OUR # 1 VHF. IT WAS WRITTEN UP IN THE MAINT LOG AS INTERMITTENT BY US.

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.