355 ° 75 ° ADF HDG 075° 075 ° ADF HDG 355° 355 ° 0  1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 INBOUND INTERCEPTION 355 ° 355 ° 33 30 24 21 15 12 6 3 W S E N 33 30 24 2I$^{I5}$ I2 6 3 33 30 24 21 15 12 6 3 W S E N 33 30 24 2I I5 I2 6 3 Station OBS N E S W 3 33 2 4 2 1 15 12 30 6 NAV GS Instrument view is from  the pilot’s perspective,  and the movable card is  reset after each turn The courses oriented FROM the station are called radials. The  VOR information received by an aircraft is not influenced  by aircraft attitude or heading.  [Figure 9-10]  Radials can  be envisioned to be like the spokes of a wheel on which the  aircraft is on one specific radial at any time. For example,  aircraft A (heading 180°) is inbound on the 360° radial; after  crossing the station, the aircraft is outbound on the 180°  radial at A1. Aircraft B is shown crossing the 225° radial.  Similarly, at any point around the station, an aircraft can be  located somewhere on a specific VOR radial. Additionally,  a VOR needle on an RMI always points to the course that  takes you to the VOR station where conversely the ADF  needle points to the station as a RB from the aircraft. In  the example above, the ADF needle at position A would be  pointed straight ahead, at A1 to the aircraft’s 180° position  (tail) and at B to the aircraft’s right.  The VOR receiver measures and presents information to  indicate bearing TO or FROM the station. In addition to the  navigation signals transmitted by the VOR, a Morse code  signal is transmitted concurrently to identify the facility, as  The ground equipment consists of a VOR ground station,  which is a small, low building topped with a flat white disc,  upon which are located the VOR antennas and a fiberglass  cone-shaped tower.  [Figure 9-11]  The station includes an  automatic monitoring system. The monitor automatically  turns off defective equipment and turns on the standby  transmitter. Generally, the accuracy of the signal from the  ground station is within 1°. VORs are classified according to their operational uses. The  standard VOR facility has a power output of approximately  200 watts, with a maximum usable range depending upon  the aircraft altitude, class of facility, location of the facility,  terrain conditions within the usable area of the facility, and  other factors. Above and beyond certain altitude and distance  limits, signal interference from other VOR facilities and a  weak signal make it unreliable. Coverage is typically at least  40 miles at normal minimum instrument flight rules (IFR)  altitudes. VORs with accuracy problems in parts of their  service volume are listed in Notices to Airmen (NOTAMs)  and in the Airport/Facility Directory (A/FD) under the name  of the NAVAID. well as voice transmissions for communication and relay of  weather and other information. VOR Components 9-10 225 °  180 °  360 °  A  B  A-1  Magnetic North  Magnetic South  Figure 9-9. Interception of bearing. Figure 9-10.  VOR radials.