SBCT Final EIS - Govsupport.us

Chapter 3 ⎯ Affected Environment3.1.12 AIRSPACE RESOURCESThe Federal Aviation Administration (FAA) is responsible for the control and use of navigable airspacein the U.S. The definition of airspace includes vertical and horizontal boundaries and time ofuse. In addition to airspace, the FAA manages the air navigation system, equipment, airports, and therules and regulations relating to powered flight. The FAA is responsible for managing the airspace forcommercial airliners and air carriers, general aviation, and government agencies, including the U.S.military.Aircraft operate under two distinct categories of operational flight rules: visual flight rules (VFR) andinstrument flight rules (IFR). These flight rules are linked to the two categories of weather conditions:visual meteorological conditions (VMC) and instrument meteorological conditions (IMC). VMC existduring generally fair to good weather, and IMC exist during time of rain, low clouds, or reduced visibility.During VMC, aircraft may operate under VFR, and the pilot is primarily responsible for seeingother aircraft and maintaining safe separation. During IMC, aircraft operate under IFR and air trafficcontrol (ATC) exercises positive control over all aircraft in controlled space and is primarily responsiblefor aircraft separation.The FAA has designated six classes of airspace. Airspace designated as Class A, B, C, D, or E is controlledairspace. Class G airspace is uncontrolled airspace. Within controlled airspace, ATC service isprovided to aircraft in accordance with the airspace classification (Class A, B, C, D, or E). Aircraftoperators are also subject to certain pilot qualification, operating rules, and equipment requirements.Within uncontrolled airspace (Class G), no ATC service to aircraft is provided, other than possibletraffic advisories when the air traffic control workload permits and radio communications can be established.Essentially, the controlled airspace system protects IFR aircraft from VFR aircraft duringinstrument meteorological conditions and in close proximity to busy airports.Use of airspace is required for the successful operation of the U.S. military. Some military flight activitiesare not compatible with civilian uses of airspace, and some military activities potentially conflictwith other uses of military airspace. Airspace restrictions are needed within military installationsto ensure safety and to avoid possible conflicts of airspace use.Large segments of controlled and uncontrolled airspace have been designated as special use airspace.Operations within special use airspace are considered hazardous to civil aircraft operating in the area.Consequently, civil aircraft operations may be limited or even prohibited, depending on the area. Specialuse airspace is divided into prohibited, restricted, warning, alert, and military operations area(MOA).MOAs are airspaces designated for non-hazardous military flight training, and they were establishedto minimize interaction between high-speed military aircraft and civilian air traffic. These areas includehorizontal coordinates (i.e., latitude and longitude), vertical zones (i.e., base and ceiling), userestrictions, and exclusions. Restricted areas denote the existence of unusual, often invisible hazardsto aircraft, such as artillery firing, aerial gunnery, or guided missiles. Consequently, flights from nonparticipatingcivilian or military aircraft are prohibited during certain training exercises.Most of the airspace above Oahu is controlled airspace (USAG-HI 2004). The airspace over southernOahu is dominated by the Class B airspace that lies above and around Honolulu International Airport.Other airports on the island are covered by Class D airspace. Elsewhere, the airspace not designatedas Class A, B, C, D, or E airspace is uncontrolled or Class G airspace from the surface to a ceiling ofeither 700 or 1,200 feet. Above this, the rest of the island is covered with either Class E controlledairspace or special use airspace.February 2008 3–88 2/25th SBCT Final EIS