Surface-Air Recognition Banner
 
 
 
 Figure 6-9 Surface-to-Air Recognition Banner
 

 
Section G. Navigation Equipment

 
Introduction
 All aviation-qualified Auxiliarists are trained to understand, operate, and interpret the navigation equipment discussed in this section.
 
G.1.  VOR Receiver
 VHF VOR navigation receivers operate in the frequency range of 108.000 MHz to 117.950 MHz and receive signals from ground VOR stations.  These signals provide azimuth information to the aircraft.  This information is displayed as the magnetic bearing either to or from the VOR station.  The term used to describe the azimuth information is the “radial” from the station.  For practical purposes, this is the magnetic bearing from the station.  If the aircraft were on the 140 radial of the Harvey VOR, the magnetic bearing from the Harvey VOR to the aircraft would be 140 degrees.  If the aircraft were to fly directly to the station, it would fly a 320-degree heading (the reciprocal of 140 degrees).
 
G.1.a.  VOR Audio Transmission
 VORs are equipped to transmit some form of audio signal (Morse code or recorded voice) that is used to verify the identity of the station.
 
G.1.b.  VOR Nautical Mile Calculation
 VOR/TACAN (VORTAC) or VOR/DME stations have the additional ability to provide signals that may be used to compute the distance in nautical miles between the aircraft and the station.  The VOR, VORTAC, and VOR/DME signals are line of sight.  The computers within the typical navigation receivers and DME will display range and bearing to/from the station and, in the case of a VORTAC or VOR/DME, will display the range, ground speed, and time to the transmitting station, if a direct path is flown.
 
G.1.c  VOR Voice Transmission
 Some navigation/communication transceivers have controls which cut out the reception of voice transmissions from the VOR/VORTACs.  Ensure the controls are set to receive the voice information when listening on navigation frequencies.
 
G.2.  Automatic Direction Finder
 The automatic direction finder (ADF) receiver may be tuned to frequencies from 200 to 415 kHz for low frequency radio beacons and from 535 to 1605 kHz to cover the standard AM broadcast band.  When tuned to a station, the needle of the indicator will point toward the transmitting station, which also transmits a three-letter identification code, except during voice transmissions.  The course may be displayed either as a bearing relative to the heading of the aircraft or as a magnetic bearing from the aircraft to the station.  These beacons are subject to errors caused by various kinds of disturbances, such as lightening storms.
　
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