identifiers for Navy airports start with N, in contrast to Norfolk International Airport (ORF) and Hampton Roads Executive Airport (PVG)
Source: VFR Map
Three-letter codes are assigned by the Federal Aviation Administration and the International Air Transport Association (IATA) to airports that receive scheduled route air carriers, have a staffed air traffic control facility, or are designated by the U.S. Customs Service as Airports of Entry.
The nine airports in Virginia with scheduled commercial passenger service now are:
The three airports in Virginia that formerly had scheduled passenger service are:
The three-letter codes reflect the location of the airport or the name of the airfield. For some, the link between codes and airport are easy to understand: LYN for Lynchburg, ROA for Roanoke, RIC for Richmond, and DAN for Danville.
Shenandoah Valley Regional Airport (SHD) and Charlottesville-Albemarle (CHO) Airport are separated by the barrier of the Blue Ridge, including Shenandoah National Park
Source: ESRI, ArcGIS Online
Other codes require understanding the story of the facility. Newport News/Williamsburg International Airport (PHF) was originally called Patrick Henry Field, and the PHF code has survived several renamings of the airport.
Codes must be distinct. SHV applies to the Shreveport, Louisiana airport, so Shenandoah Valley was assigned SHD. CHA applies to Chattanooga's airport, so Charlottesville uses CHO. HOT was already used by Hot Springs, Arkansas, so Hot Springs, Virginia used HSP.
Reagan National Airport's code, DCA, is shorthand for District of Columbia Airport. What was known originally as National Airport was built at a location that was primarily within the boundaries of the Federal district, based on the charter granted to Lord Calvert by Charles I in 1632. An official act of Congress was required to clarify that dredging and filling the bed of the Potomac River had altered the high-water mark boundaries. As a result, the airport with a code reflecting its location within the District of Columbia is in... Virginia.
The Norfolk civilian airport could not use a code starting with "N" because codes that start with that letter are reserved for facilities of the US Navy. For example, NTU is the code for Naval Air Station Oceana. Norfolk's airport code dropped the first letter of the city's name and is derived from nORFfolk. 1
Dulles International Airport could have chosen DIA because no airport uses that three-letter code. Airport officials chose to reverse the letters and use IAD (International Airport Dulles), to avoid potential confusion with nearby National Airport and its DCA code. That decision reduced the potenial that baggage labelled DIA and DCA could have ended up at the wrong airport. The Federal Aviation Administration now requires that airports must be 200 miles apart before they can share two sequential letters in the three-letter code.
Before the Federal Aviation Administration stopped issuing three-letter codes for entire metropolitan areas, the Washington, DC area was assigned the WAS code. Trip planners using search engines such as Expedia still can use that WAS identifier to seek out flights from multiple airports in the DC/Maryland/Northern Virginia region. Hampton Roads residents have no equivalent three-letter code to use on a search engine to find flights from the three separate airports that serve Richmond, Newport News/Williamsburg, and Norfolk.2
the WAS code can be used to search for flights from all three commercial airports in the Washington, DC metropolitan area
The International Civil Aviation Organization (ICAO) issues four-letter airport codes for airports. In Virginia and most of the United States, they all starting with "K."
The nine airports in Virginia that offer scheduled commercial passenger service today are also General Aviation airports. Their three-letter airport codes are modified by adding a "K" in front, so the international identifier for Dulles International Airport is KIAD. The military airport at Fort A. P. Hill uses the three-letter identifier of APH and the four-letter identifier of KAPH.
The Federal Aviation Administration codes for Virginia airports use the same three-letter codes assigned by the International Air Transport Association, and the four-letter codes assigned by the International Civil Aviation Organization.3
1. "Airport ABCs: An Explanation of Airport Identifier Codes," http://www.skygod.com/asstd/abc.html (last checked December 31, 2016)
2. "Location Identifiers," Federal Aviation Administration, Order JO 7350.9G, September 15, 2016, p.1-2-2, p.1-2-5, https://www.faa.gov/documentlibrary/media/order/7350.9g_location_identifiers.pdf (last checked December 31, 2016)
3. "Airport ABCs: An Explanation of Airport Identifier Codes," http://www.skygod.com/asstd/abc.html (last checked December 31, 2016)