Airport Height Zones
The Airport Height Zones have nothing to do with zoning districts (although they are codified in the zoning regulation - AMC 21.65.) They are mandated by Part 77 of the Federal Airway Regulations to provide safe approach paths to certain airports. The four affected airports in the municipality are Anchorage International Airport, Merrill Field, Birchwood airport, and Girdwood airport.
The Airport Height Zone contours are shown on the zoning maps. The contours give the maximum elevation above mean sea level (MSL) allowed for structures, including radio antennas. Plot plans for building and land use permits within Airport Height Zones may be required to show elevations referenced to mean sea level to verify that structures don't encroach vertically into the airport approaches.
If you use the online version of the code, try searching on "21.65.010" for more information. Please note that recent amendments may not have been published yet. Land Use Enforcement will be happy to verify the current code language for you.