Radio Navigation

Question 1

Radio Navigation: (Definition)

Types of Radio or Electronic Navigation: (3)

Answer 1

•An electronic method of navigation from a source outside the aircraft used for situational awareness and navigation.

•Types of Radio or Electronic Navigation
–Air / Ground Systems (VOR, NDB, GPS, ADS-B)
–Ground Controlled Systems (ATC Radar)
–Self Contained Systems (INS)

Question 2

Use of Radio Navigation:

Appropriate Use:

Inappropriate Use:

Answer 2

•Appropriate Use
–Use in conjunction with Pilotage and Dead Reckoning
–Guidance during times of reduced visibility
–Establish orientation
–Enhance Situational Awareness

•Inappropriate Use
–Sole Navigation Reference
–Substitute for Preflight Planning

Question 3

How accurate is GPS?

Answer 3

•Position Accuracy is approximately within 100 meters, 95% of the time

Question 4

GPS TRIVIA:

How long does it take a GPS signal to travel from satellite to Earth?

How fast do GPS signals travel?

How fast is the nanosecond accuracy?

If clocks are off by 1/100th of a second how big of an error does that cause?

Answer 4

• GPS signals take 6/100ths of a second to go from the satellite to the earth
• GPS signals travel approximately 186,000 miles per second
• Nanosecond accuracy – 0.000000001 seconds
• If the clocks are off by 1/100th of a second that equals a 1,860 mile error.

Question 5

RAIM:

What does RAIM stand for?
What does it do?
How many satellites are required?
Without RAIM what are we left without?

Answer 5

•Receiver Autonomous Integrity Monitoring

–The error check. The GPS is checking the integrity of the signal.

–5 satellites required

–“Without RAIM capability, the pilot has no assurance of the accuracy of the GPS position.”

Question 6

VOR: What does VOR stand for?

What is the frequency range?
What phase occurs when you transmit two signals?

What phase is it when transmitted all the way around?

How fast does it rotate?

What does VOR do?

Answer 6

•Very High Frequency Range
–108.0-117.95

•Transmits two signals
–Reference Phase

•Same all the way around
–Variable Phase•Rotates at 1800 RPM

•Measures the phase difference

Question 7

Types of VOR: (3)

Answer 7

• VHF Omni-Directional Range (VOR)
• VORTAC
• VOR-DME

Question 8

Advantages (3) and Disadvantages (3) to VOR use:

Answer 8

•Advantages
–Concise form of Navigation
–Easy to interpret position
–Not heading sensitive

•Limitations
–Line of Sight
–Range

Question 9

VOR Radials:

How many are there?
How many directions can they be flown?

Is the heading sensitive?

Answer 9

• 360 different radials, that can each be flown in 2 directions
• Is not heading sensitive

Question 10

Factors that effect VOR Frequency Reception

Answer 10

• Altitude
• Class of facility (service volume)
• Location of facility
• Terrain

Question 11

Identifying a VOR Station:

What must you do prior to using?

How do you identify?

Answer 11

•Must do prior to using the VOR
– Ensure correct station is selected
– Ensure station is working

•Morse code identification

Question 12

Components of a VOR or GPS indicator

Answer 12

• Omnibearing Selector (OBS)
• Course Deviation Indicator (CDI)
• To-From Indicator

Question 13

CDI Sensitivity

Answer 13

•“Full scale needle deflection”

•GPS enroute
–5 miles
–2 miles (WAAS equipped)
–Sensitivity remains constant

•VOR
–10 degrees
–Navigation becomes more sensitive as you get closer to the VOR ground antenna

Question 14

G1000 dots as opposed to Traditional dots

Answer 14

G1000 = 2 dots
Traditional = 5 dots

Question 15

Interpreting VOR direction

Answer 15

• Turn the OBS so that the CDI is aligned
• Make sure that it has a FROM indication
• Draw out where you are in relation to the station

Question 16

VOR Terms:

Cone of confusion:
Zone of Ambiguity:

What do they both result in?

Answer 16

• Cone of confusion: Area directly above the VOR where there is no clear indication to the aircraft which radial it is currently on.
• Zone of ambiguity: Area perpendicular to the selected course where the aircraft does not have a clear indication if it is the TO or FROM side of the VOR.
• Both result in a OFF or NAV indication.

Question 17

Recognizing Lost NAV: (3)

Corrective Actions (3)

Answer 17

• NAV/OFF flag appears
• Morse Code no longer heard
• Inoperative CDI

•Corrective Actions
–Pilotage and Dead Reckoning
–Secondary radio navigation
–ATC

Question 18

Flying A Course: GPS Vs. VOR

Answer 18

GPS
•Able to navigate to any waypoint in the database
–Airport
–Any NAVAID
–Airway Intersection
–User created waypoint

VOR
•Ground antenna
–Commonly located at airports

Question 19

VOR / GPS Tracking(2)

Answer 19

• Fly from one point to the other keeping the CDI centered

* Bracket by keeping a stabilized crosswind correction

Question 20

Reverse Sensing:

Definition
Common mistake by setting what incorrectly?

If wrong course is set in what will happen?

Answer 20

• Definition: CDI will indicate the opposite of the actual indication– right means left.
• Common mistake by setting in the incorrect OBS setting

•If wrong course is set in:
– Needle will move farther away when correcting

Question 21

Avoiding Reverse Sensing: (3)

Answer 21

• Make sure that OBS course matches Aircraft Heading
• If you want to head TO the station line up TO indication

•If you want to head FROM the station line up FROM
Indication

Question 22

VOR Cross Checking

What is it?
How is it done? (3)

Answer 22

•Use two VORs to find your exact position

– Center both VORs with a from indication
– Draw out the radials
– Where they cross is where you are at

Question 23

Intercepting a VOR/GPS

How do you do it?

Answer 23

• Set the OBS
• Turn the aircraft to parallel the course
• The intercept heading will be in the same direction that the CDI is deflected

Question 24

What should intercept angle be? (3 Common Angles)

Factors? (3)

Answer 24

•What should the intercept angle be?
–30⁰, 45⁰, 60⁰ angles are common

•Factors:
–Wind
–Distance from the station/airport
–Ground speed

Question 25

Automatic Direction Finder (ADF)

Answer 25

•What should the intercept angle be? –30⁰, 45⁰, 60⁰ angles are common •Factors: –Wind –Distance from the station/airport –Ground speed

Question 26

Advantages and Limitations of ADF

Answer 26

Advantages: •Simple •Reliable •Not restricted to Line of Sight Disadvantages: •Twilight/Night Effect •Static/Lightening Effect

Question 27

Ground Equipment for ADF: What does it transmit on and in what directions? What are frequencies used?

Answer 27

•Non-directional Radio Beacon (NDB) –Transmits the same signal in all directions –190 through 1750 kHz

Question 28

# DEFINE: Relative Bearing: Magnetic Heading: Magnetic Bearing: •RB + MH = MB

Answer 28

•Relative Bearing –What is read from the Indicator –Degrees from nose of aircraft to the station •Magnetic Heading –What is read from the Heading Indicator –Degrees from North to nose of aircraft •Magnetic Bearing –Where you are in relation to the station –Degrees from north to the station •RB + MH = MB

Question 29

WAAS: What does WAAS it stand for? What happens to GPS Position Accuracy? What does WAAS do?

Answer 29

* Wide Area Augmentation System * GPS position accuracy goes from 100 meters to 7 ``` •WAAS utilizes a ground antenna network covering the United States to determine GPS error –Ground reference station (25) –Master station (2) –Geostationary satellite –Ground uplink station (4) ```

Question 30

LAAS: What does it stand for? What is accuracy for LAAS? How many ground antennas does LAAS use to determine gps error with, and what is the radius? Previous version was known as what and what is it now used for?

Answer 30

* Local Area Augmentation System * LAAS can achieve measurement accuracies of better than one meter * LAAS utilizes four ground antennas to determine GPS error within a 20 – 30 nm radius * A previous version known as “differential GPS” still exists today with agricultural applications