Any Unknown or Unlisted Aircraft Manufacturer
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown; Other / Unknown
ATC Issue All Types; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Provided Assistance; Flight Crew Became Reoriented; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action
ATC Equipment / Nav Facility / Buildings; Human Factors; Weather
Received my IFR clearance from FAI FSS over the HSL RCO. Was monitoring the ANC Center frequency 127.0 prior to takeoff and tried to contact them multiple times between 10 and 25 DME east of Huslia at altitudes between 4;000 feet and 9;000 feet. Although I could hear Anchorage Center; they could not receive my transmissions. I tried on both radios as well. Began accumulating moderate to severe mixed icing at 9;000 feet; and requested a block altitude between 9;000 feet and 11;000 feet in the blind. I tried identing; with no response from ATC. I also tried to relay my request and concerns [through another] aircraft on frequency; but that pilot was also not able to reach ATC. I then made the decision to squawk 7600 for lost communications; and climbed to 10;000 feet where I was in clear skies above the layer where the icing was occurring. About this time; I heard ATC query my altitude and another aircraft (not the aircraft [I tried talking through]) said they heard me request an immediate request to be given a block altitude. I could still hear ATC; but they could not hear my transmissions. ATC relayed a block altitude amended clearance and to contact center on 120.9 in 10 minutes. I went back to assigned squawk code at this time. Once able to communicate with Anchorage Center approximately 45 miles west of Tanana VOR; I told the controller I was able to hear the previous controller; but [controller] was unable to hear me.Traveling between Tanana and Galena or between Tanana and Huslia IFR there is a large dead zone where you are unable to talk to Anchorage Center. However; once you are above 5;000 feet and within 25 miles of Huslia; you are always able to contact them. Today; was not the case.There needs to be improved communications capabilities in this area! A repeater or similar device on top of Indian Mountain where there are already ATC facilities present. This would allow uninterrupted access to Anchorage Center; and be able to contact them through the current dead zones east and north of Galena.
Pilot reported deviating from assigned altitude due to experiencing aircraft structural icing while in a 'dead zone' of Anchorage Center's communications equipment radio coverage.