Instrument flight rules

Note. HCI = human computer interaction VFR = visual flight rules IFR = Instrument flight rules ATC = air traffic control. 

Instrument Flight Rules Flight rules that require aircraft to be under positive air traffic control. 

Air Route Traffic Control Centers (ARTCCs). The air traffic control system is divided into twenty-two ARTCCs that manage traffic within specific geographical areas. The ARTCCs are responsible for all traffic other than that controlled by the terminal radar approach control (TRAGON) and the control tower facilities. Primarily utilizing constant radar surveillance, the ARTCCs provide separation for aircraft operating in controlled airspace under instrument flight rules. 

Instrument Flight Rules (IFR) Navigation using only instruments inside the aircraft to fly the plane. 

Bennett, C. T., M. Schwirzke, and C. Harm. Analysis of General Aviation Accidents during Operations under Instrument Flight Rules. Proceedings of the Human Factors and Ergonomics Society Annual Meeting, 1990, 1057-1061. 

Information relevant to the services provided to aircralt operating in accordance with both visual flight rules and instrument flight rules in the seven ATS airspace classes is contained in 2.6.1 and 2.6.3 of Annex 11. A pilot may elect to fly in accradance with instrument flight rules in visual meteorological conditirais or may be required to do so by the appropriate ATS authority. Standard 2.1.2. 

Visual Flight Rules Navigation that uses visual cues with only occasional reference to instruments inside the cockpit. 

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