Dash 8 Series Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Confusion
ATC Issue All Types; Inflight Event / Encounter Weather / Turbulence
Flight Crew Diverted
Human Factors; ATC Equipment / Nav Facility / Buildings; Airport; Procedure
Due to faulty ASOS equipment the visibility was reported by the ASOS as 'Missing'. Without the proper visibility being reported; we were required to divert to PGV and land. Faulty FAA ground equipment and lack of an approved weather observer at night in EWN. The FAA will not allow us to land. Contacted Dispatch; and EWN operations; and diverted. The FAA will not allow us to land under Part 121 even if we have the required inflight visibility. It must be reported on the ground by an approved source. This needs to be changed! If the flight crew believes the weather report is inaccurate; and has the required inflight visibility; they should be able to land the aircraft. These rules defy common sense; and should be modified. Problems with the ASOS in EWN continue to be a problem where incorrect visibility is often reported by this machine due to its close proximity to Bryce's Creek and advection fog obscuring the machine; and not the airport. My suggestion for improvement would be to either have the FAA move the ASOS machine to a more suitable location; or do what we used to do by training some of our ramp employees to be certified weather observers and give them the ability to correct the ASOS machine if it is in error.
Air Carrier Captain laments the requirement to divert when the visibility is missing from the ASOS report for their destination airport and no approved weather observer is available.