Small Transport
Flight Crew Multiengine; Flight Crew Commercial; Flight Crew Instrument
Flight Crew Last 90 Days 150; Flight Crew Total 1506; Flight Crew Type 500
Confusion; Communication Breakdown; Distraction
ATC Issue All Types; Ground Event / Encounter Ground Equipment Issue; Inflight Event / Encounter Other / Unknown
Flight Crew Requested ATC Assistance / Clarification; Flight Crew Overcame Equipment Problem
ATC Equipment / Nav Facility / Buildings; Airport
This is a recurring issue. FNL and AIA both have weather-reporting equipment on the same frequency and are only 139 miles apart from each other. Our routing typically originates east of FNL and due to ATC preferential routing; our descent into FNL typically takes us over the GLL VOR/DME.  As a result of the interference between the AIA ASOS and FNL ATIS; neither station can be understood during the initial descent. When arriving into FNL; the ATIS is unreadable until we're approximately 30 miles from the airport; and by then we're already talking to Denver Approach and usually getting vectored for an approach. Likewise; descending into AIA; the ASOS is unreadable until we're about 50 miles out. I suppose it goes without saying that changing the frequency of one of these two stations seems like the best solution; but I know that reducing the power of either station could be an option as well. Personally; while I know the aviation frequency spectrum is crowded; I really hope that an effort is made to find an unused frequency for one of these two facilities.
A pilot reported FNL and nearby AIA use the same frequency for ATIS/ASOS causing the radio transmissions to be garbled and unreadable. They are unable to acquire required airport information in a timely manner prior to landing.