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HOMEWORK. Read Jeppesen Section 9 B & C Gleim chapter 10 (33 questions 10 will be on your next quiz) ASA Chapter 10 PHAK CHAPTER 15 15-21 TO 15-35 AIM SECTION 1. ASA. You should have studied all of the following questions to date:
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HOMEWORK • Read Jeppesen Section 9 B & C • Gleim chapter 10 (33 questions 10 will be on your next quiz) • ASA Chapter 10 • PHAK CHAPTER 15 15-21 TO 15-35 • AIM SECTION 1
ASA • You should have studied all of the following questions to date: • Chapter 1, 2, 3, 4-28 to 4-34, 5-1 to 5-18, 8, 9, 10, 11
Private Pilot Ground School • Radio Navigation
RADIO NAVIGATION • VOR ground facilities • Frequencies • Aircraft VOR equipment (OBS, CDI, TO/FM) • Use of equipment • DME • Transponder • ADF
VOR Simulator • http://www.visi.com/~mim/nav/
The VOR • What does VOR stand for? • VHF Omni-directional range • Omni = means all • 108.0 to 117.95 MHz • Operational for line of sight only • Accuracy to within +/- 1˚ • Morse Code is the only way to ID for sure • Test -….- code is for alerting pilots when maintenance is being done. • Course or radials referenced to magnetic north
Cone of Confusion • Jepp Page 9-25 • Will have a NAV flag when flying in the cone of Confusion and when the aircraft is directly abeam the station. • Also get a NAV flag anytime the VOR is not receiving a reliable signal.
The VOR Sure its cool, but how does it work? • It radiates 2 signals • 1st one is in all directions (Omni-directional) • 2nd one is rotated about a point (Directional) • Airplane receives both signals, looks at the difference between the 2, the result is the radial • 360˚ the two signals are in phase • 180˚ the two signals are out of phase by ½ • 270˚ the two signals are out of phase by ¾ • Read Jepp page 9-22
The VOR • Course Roughness • Irregularities caused by terrain • RPM settings may cause fluctuations • The Cone of Confusion • The VOT • VOR Ground Checkpoint • Accuracy of the tests • AFD
The VOR Head • The VOR • OBS Omni-bearing Selector (sometimes referred to as course selector) • CDI Course Deviation Indicator • The scale is 10˚ either side, each dot is 2˚ • Ambiguity Indicator TO/FROM and OFF or NAV
The white flag is the active indication for the ambiguity indicator The VOR
DME (Distance Measuring Equipment) pg 9-30 • Freq Range 962 to 1,213 MHz • Usually co-located with VOR • Usually freq is paired with VOR so that when you select VOR freq you get DME freq automatically. • DME may exist on its own or with another nav aid such as ADF but will have a VOR freq. published for access. • Required by FARs above 24,000 feet
DME • DME comes in three yummy flavors: • VOR/DME • VORTAC • TACAN • Operates in the 960-1215 MHz UHF range, transmitting in the range of 960-1024 MHz and 1151-1215 MHz and receiving in the 1025-1150 MHz range
DME • DME is an active system • There is a transmitter and receiver on both ends • Airborne unit sends signal to ground unit • Ground unit replies • Airborne unit measures the time it takes • 12 microseconds = 1 mile for a radio wave • A pair of pulses is sent out specific to that airborne unit • Max range is 200 NM • Slant range (in practical application the DME readings can be considered accurate if the airplane is over 5 miles from the station.
DME and ground speed • If doing an arc around a station GS = 0 • Accurate is going to or from station.
The Transponder • May be thought of as a microwave transmitter/receiver. • The radar antenna is also a transmitter/receiver • It will overpower the transponder so it cycles on and off 800 times a second with a target 40 miles out • Primary radar – just picks up reflected energy • Secondary radar – picks up transponders reply
Transponder • The transponder works like this. The ground radar equipment sends out a special interrogation signal asking all aircraft, “Who are you?”. Only transponder equipped aircraft can answer. The airborne transponder picks up the signal and automatically sends back a strong pulsed signal in reply. The reply signal is computed into distance and direction (mode c altitude as well) by the ground station and is displayed with the aircraft’s target on the controllers scope.
Transponder • 4096 code capability • 1200 VFR • 7500 unlawful interference i.e. hijacking • 7600 Com failure • 7700 Emergency • VFR Flight Following
The ADF/NDB • MH+RB=MB • 190-415 and 510-535 KHz band
ADF ANTENNAS • Sense antenna, is a non-directional antenna that has the capability of providing directional information. Usually a long wire installed on the top of the airplane • Loop antenna, a metal ring enclosing coils of insulated wires, is usually contained within a streamlined housing mounted well forward of the underside of the fuselage. Senses magnetic bearing from the airplane to the station.
Switch • 5 positions • ADF position used for navigation • REC position or ANT selects only the non-directional or sense antenna. The loop antenna and there fore the bearing selector are disconnected from the system. In this position operates as a L/MF receiver. Used for listening only or station identification.
Switch • EXR = extended range, permitting strong reception of stations at greater distance. • BFO = Beat frequency oscillator selection provides an aural aid to tuning. It should be used only in tuning unmodulated signals, such as those broadcast by stations in some foreign countries. In North America it is not needed since modulated signals are used. In BFO the underlying morse code identifier can be heard through the audio tone of the unmodulated signal. After the station is tuned and identified, the function selector shold be repositioned to ADF
ADF SIMULATOR • http://www.luizmonteiro.com/Learning_ADF_Sim.aspx
The ADF/NDB • The ADF is in the airplane • The NDB is on the ground • Basically an AM radio station designed for navigation use. • If fact you can tune in AM radio stations for. • NDBs usually operate in the L/MF (low to medium frequency) of 190 to 535 kHz
The ADF/NDB • How about that switch with all the funny abbreviations? • ADF puts the unit in nav mode, uses the loop (gray box) antenna on the bottom of the aircraft and sense • ANT puts the unit in receive mode and switches to the big long antenna that goes from the top of the cabin to the tail. • BFO puts the unit in Beat Frequency Oscillator. This selection provides an aural aid to tuning. It should be used only in tuning unmodulated signals, such is in some foreign countries. The BFO allows the underlying morse code identifier to be heard through the audio tone of the unmodulated signal. After tuned you would turn back to ADF • Modulated means to change some characteristic, such as amplitured, frequency, or phase of an alternating current wave.
The ADF/NDB • ADF interpretation • MH + RB = MB to • MH is given info for fixed card • For moveable cards read the heading at the top • RB is the bearing measured clockwise from the nose of the aircraft • MB is the bearing measured clockwise from North
The needle points to the magnetic bearing to To get Relative Bearing use your formula Figure 1 MH + RB = MB to 330 + RB = 210 RB = 120 (210-330) Take 360-120 =240 RB to OUR AIRCRAFT HAVE FIXED CARDS Moveable card ADF/NDB
To get Relative Bearing use your formula Figure 2 MH + RB = MB to 315 + RB = 190 RB = 125 (190-315) Take 360-125 =235 RB to Moveable card ADF/NDB
Fixed Card ADF/NDB • On these, the needle points to the RB to • For MB use your formula • Figure 4 MH of 320 • MH + RB = MB to • 320 + 225 = 545-360=185 • To get the bearing from don’t forget to add 180
GPS 1-1-19 • There are 24 satellites in the constellation • They sit at 10,900 miles and orbit in about 12 hours • There are usually 5 that can be “seen” from anywhere on earth • The signals travel at the speed of 186,000 miles per second • This requires clocks with accuracy in the billionths of a second (1 foot equals 1 billionth of a second) • The receiver calculates a time distance problem to figure range from a minimum of 4 satellites to determine position.
RNAV • Stands for Area Navigation • Basically a VOR/DME computer • You tell it a radial and a distance and it fixes a waypoint at that location • Limitations are you have to be in range of a VOR/DME at all times • GPS is replacing this equipment
ILS • Stands for Instrument Landing System • Consists of a Localizer, which provides course guidance and a Glideslope which provides vertical guidance. • Very accurate, to within 25 feet at the threshold • AIM FIGURE 1-1-9 on page 513
LORAN C AIM 1-1-15 • Stands for Long Range Navigation • On its way out, but is dying a hard death • Works on similar principles as GPS only the stations are ground based • Additional info “LORAN-C USER HANDBOOK” http://www.navcen.uscg.gov/loran/handbook/h-book.htm • George is in the LORAN–C West Coast Chain
ADF SAMPLE QUESITONS • If the MB TO the station is 040 degrees and the relative bearing is 270 degrees what is the MH? • MH+RB=MB • MH+270=040 • MH=040-270 • MH=-230 (add 360) • MH=130