Editing Instrument flight rules (section)

==Navigation==
Because IFR flights often take place without visual reference to the ground, a means of navigation other than looking outside the window is required. A number of [[navigational aid]]s are available to pilots, including ground-based systems such as [[Distance Measuring Equipment|DME]]/[[VHF omnidirectional range|VOR]]s and [[Non-directional beacon|NDB]]s as well as the satellite-based [[Global Positioning System|GPS/GNSS]] system. Air traffic control may assist in navigation by assigning pilots specific headings ("radar vectors"). The majority of IFR navigation is given by ground- and satellite-based systems, while radar vectors are usually reserved by ATC for sequencing aircraft for a busy approach or transitioning aircraft from takeoff to cruise, among other things.{{Citation needed|date=June 2015}}