Navigation 12 Weeks Bianca L

Front 1

GPS satellites are geostationary.

Back 1

False

Front 2

Where is the GPS Master Control Station located?

Back 2

Colorado Springs

Front 3

GPS uses satellite trilateration to determine position, which essentially calculates:

Back 3

How long a radio signal takes to reach a receiver from a satellite.

Front 4

How many satellites are needed for a 3D fix?

Back 4

4

Front 5

Precise Positioning Service (PPS) is available to all GPS users on continuous, worldwide basis.

Back 5

False

Front 6

Precise Positioning Service (PPS) is available to all GPS users on continuous, worldwide basis.

Back 6

False

Front 7

Which of the following Figure of Merit (FOM) readings indicates the highest fix accuracy?
FOM 5, FOM 9, FOM 2

Back 7

FOM 2

Front 8

RADAR and microwaves can affect the integrity of the GPS signal.

Back 8

True

Front 9

_____________ is the intentional alteration and degradation of GPS accuracy.

Back 9

Selective Availability

Front 10

_________________ is designed to protect against spoofing (imitation) and unauthorized use by encrypting the P code.

Back 10

Anti-spoofing

Front 11

What are the three segments of the GPS system?

Back 11

Space, Control, User

Front 12

What does RaDAR stand for?

Back 12

Radio Detection and Ranging

Front 13

Which is not an adjustment that an operator can make to the radar to provide better resolution?

Back 13

VRM

Front 14

Navigation radars usually have a high frequency and low pulse length.

Back 14

True

Front 15

Which radar component produces the elctromagnetic waves of energy?

Back 15

The transmitter

Front 16

How many radar ranges are needed for a fix?

Back 16

3

Front 17

Which is not a functional requirements of all Electronic Charting Display and Information Systems (ECDIS)?

Back 17

Direct engine control

Front 18

ECDIS

Back 18

Civilian electronic charting system

Front 19

ECDIS-N

Back 19

US Navy electronic charting system

Front 20

ECS

Back 20

Civilian electronic charting system that does not meet international requirements. Situational awareness only.

Front 21

NGA's Digital Nautical chart s (DNC) are vector based.

Back 21

True

Front 22

NGA's Digital Nautical chart s (DNC) are in Vector Product Format and is a direct read navigational product that conforms to IHO symbology and functional content.

Back 22

True

Front 23

__________________ charts are simply bitmap images created by scanning a paper chart.

Back 23

Raster

Front 24

_____________________ charts portray charted features as points, lines, or areas with amplifying information (attributes) found in an associated database.

Back 24

Vector

Front 25

Which of the following is NOT a trial system for ECDIS-N?

Back 25

FUND

Front 26

Which three are future capabilities that are planned for ECDIS-N systems?

Back 26

1. Integrated tides, tidal currents with NAV systems.
2. Video Display of port entrances.
3. Automated visual bearings via laser range finders or mounted cameras.

Front 27

In the Northern Hemisphere, that part to the right of the storms track, where the actual wind speed is greater than that due to the pressure gradient alone and where the direction of the wind and sea will carry a vessel into the path of the storm is called the _________.

Back 27

Dangerous semi-circle

Front 28

In the least dangerous semi-circle, place the wind on the _________________, hold course and make the best speed possible.

Back 28

Starboard quarter

Front 29

That part to the left of the storms track in the northern hemisphere where the wind is decreased by the forward motion of the storm and the wind blows vessels away from the storm track is called the ____________________.

Back 29

Less Dangerous semi-circle

Front 30

In the most dangerous semi-circle, place the wind on the ______________, hold course and make best speed possible.

Back 30

Starboard bow

Front 31

___________ is a forecasting service available to ships to provide the safest and most rapid route- requested 7-10 days prior to U/W and usually for voyages greater than 1500 NM.

Back 31

OTSR

Front 32

____________ is an enroute weather foecast along Planned Intended Movement (PIM)- requested in a MOVREP.

Back 32

WEAX

Front 33

3 pieces of information in cluded in a synoptic message (weather observation).

Back 33

Seawater temperature, barometric pressure, cloud cover

Front 34

Which is NOT a Navy weather information source?

Back 34

EHF point to point

Front 35

When dew point is within three degrees of dry bulb, conditions are ripe for what?

Back 35

Fog

Front 36

What are the parameters for sending a Synoptic (weather observation) every 6 hours?

Back 36

Winds <33 kts, Seas <12 ft

Front 37

If synoptic messages must be sent out every 3 hours, they are released with a(n) ___________ precedence code.

Back 37

IMMEDIATE

Front 38

_____________ is the temperature at which fog is likely to form.

Back 38

Dew point

Front 39

___________ leads to vertical lifting, which results in cloud formation and precipitation (bad weather).

Back 39

Horizontal Surface Convergence

Front 40

Warm Front

Back 40

Leading edge of warm, moist air (mT) that slowly overrides cooler, denser air, causing weather to form ahead of it.

Front 41

Low Pressure System

Back 41

Cyclonic (CCW in the N. Hemisphere), surface convergence, leads to upward vertical motion. Associated with bad weather.

Front 42

Cold Front

Back 42

Leading edge of a cold air mass possessing asteep slope. Clouds and severe weather form ahead of the front.

Front 43

High Pressure System

Back 43

Anti-cyclonic (CW in the N. Hemisphere), surface divergence, leads to downward vertical motion. Associated with good weather.

Front 44

Air Mass

Back 44

Extremely large body of air whose properties are fairly homogeneous in any horizontal direction for a given altitude.

Front 45

Sea Breeze

Back 45

Onshore wind that forms in the afternoon due to land heating more quickly than water, causing low pressure over land.

Front 46

Triple Point

Back 46

For a mid-latitude storm, the area of most severe weather, where the cold front, warm front and occulded front meet.

Front 47

Occulded Front

Back 47

When a cold front overtakes a warm front.

Front 48

Stratus

Back 48

Low, sheet like clouds which can affect large areas and halt flight operations due to low ceilings. Light rain or drizzle.

Front 49

Meteorology

Back 49

The science of forecasting weather.

Front 50

Cumulonimbus

Back 50

Clouds of great vertical extent associated with thunderstorms and severe weather (hail, tornadoes, heavy rain).

Front 51

High Waves

Back 51

High wind speeds, wind blowing for a long time and large areas affected by the wind cause these.

Front 52

The 4 Advantages of GPS

Back 52

1. Extremely accurate.

2. Worldwide 24 hour coverage.

3. Passive system.

4. All-weather operation.

Front 53

3 Components of GPS

Back 53

1. Space Segment
2. Control Segment
3. User Segment

Front 54

Space segment of GPS

Back 54

-24 satellites (+4 spares)
-Broadcasting position and time information on 2 frequencies
-Very high orbit for accuracy, survivability and coverage

Front 55

Control segment of GPS

Back 55

Consists of the Master Control Station (MCS), 5 monitor stations and 4 ground transmitters.

Front 56

What do the 5 Monitor Stations

Back 56

-Passively track satellites in view
-MCS processes data & updates satellites nav message
-Updated Info is transmitted to satellites via 4 ground antennas

Front 57

User segment of GPS

Back 57

-refers to anybody, anywhere using a GPS receiver
-Dual Use System Since 1985
(civil & military)

Front 58

What does RADAR stand for?

Back 58

Radio Detection and Ranging

Front 59

Navigation radars usually have a _____ frequency and _____ pulse length which causes them to have higher resolution, but shorter range.

Back 59

usually have a HIGH frequency and LOWpulse length which causes them to have higher resolution, but shorter range.

Front 60

What are the 5 components of the RADAR

Back 60

1. Transmitter -produces electromagnetic waves of E
2. Modulator- circuitry that turns the transmitter on and off
3. Antenna- transmits outgoing pulses ans receives returning echoes
4. Receiver- amplifies very weak returning echoes and demodulates them for display
5. Display- uses a cathode ray tube

Front 61

What are 5 limitations of Radar?

Back 61

1. Subject to mechanical and electrical failure
2. There are maximum and minimum range limitations
Interpretation of display can be difficult
3. Less accurate than visual piloting
4. Small object may not be detected in high sea states
5. Requires transmission form the ship, which may not be tactically desirable
6. Resolution in Bearing- the minimum difference in bearing between two objects at the same range that can be separated y the radar. It is directly related to beam width. A typical surface navigation radar will transmit a signal with a width of approximately 1 degree.
7. Resolution in Range- the minimum difference in range between two objects on the same bearing that can be separated by a radar. Directly related to pulse length.
8. Blind Spots
9. Ground Waves

Front 62

What are three uses of navigation radar?

Back 62

1. Anti-Collision- track surface contacts, CPA info
2. Navigation- bearing and range info to nav aids
3. DivTacs- monitor ship's position in relation to guide

Front 63

What are 3 filters used to optimize radar display?

Back 63

1. Rain- blocks unwanted radar return form rain or atmospheric conditions
2. Sea- blocks return caused by sea clutter
3. Gain- adjustable radar input which determines the amount of power the radar is transmitting.

Front 64

What is the minimum and maximum radar range?

Back 64

Minimum Range- a radar cannot receive a returning echo until the trailing edge of the pulse has cleared the antenna and the transmit/receive switch has been switched to receive. Typically, minimum range is 12 yards.

Maximum Range- determined by the height of the antenna, the power output and the frequency. Maximum range is usually limited by the curvature of the earth to line of sight or slightly greater since high-frequency radio waves travel in a straight line

Front 65

Who determines ranges to radar nav aids and passes information to plotter.

Back 65

Radar Operator

Front 66

Who plots radar ranges on chart to determine ship’s position.

Back 66

Plotter

Front 67

Who evaluates fix and passes a fix report to the Navigator.

Back 67

Piloting Officer

Front 68

Who uses the radar to track shipping

Back 68

Shipping Officer

Front 69

Who passes all information to the bridge

Back 69

Phone Talker

Front 70

Who receives the information from CIC and reconciles it with the information provided from the Bridge Nav team in order to give a Navigation report to the OOD and Captain

Back 70

Navigator

Front 71

What are the two major types of electronic charts?

Back 71

Raster and Vector

Front 72

What is the basic difference between raster and vector charts?

Back 72

Raster charts are simply bitmap images created by scanning a paper chart while vector charts portray charted features as points, lines, or areas with amplifying info (attributes) found in an associated database

Front 73

What are advantages of raster charts?

Back 73

1. looks like a paper chart
2. cheap and easy to produce
3. runs easily on PC
4. world-wide availability

Front 74

What are raster concerns?

Back 74

1. require a lot of CPU's memory
2. zooming degrades quality
3. mixed pixels

Front 75

What are advantages of vector charts?

Back 75

1. Info on chart can be linked to specific points
2. allows the user to display the info that is necessary for the ship's current mission

Front 76

What are benefits of ECDIS (GPS and chart data in digital format)?

Back 76

- Real time position / Automated plotting
- Data / Information display and manipulation
- Reduce Manning
- Improved Safety
- Enhanced Command and Control
- Increased awareness in low visibility

Front 77

Short explanation of ECDIS

Back 77

ECDIS is a system that is able to display electronic chart information with automatic position updates that has a built in redundancy that will assist the mariner in all aspects of Navigation. It is the legal equivalent of a paper chart.

Front 78

What are the ECDIS display standards?

Back 78

-Display “North-up”, other orientations permitted
-Colors and Symbology (i.e. IHO symbols)
-Own ship displayed at true scale or as symbol
-Day, dusk, night colors
-Automatically resets and generates neighboring areas as determined by the operator
-Time-labels on ship’s track

Front 79

Risks of ECDIS

Back 79

-ECDIS is only a tool that helps a mariner safely and effectively navigate a ship.
-It is not the end-all be-all to ship navigation.
-One of the biggest risks with the transition to ECDIS is an over reliance in the information provided
-Poor GPS performance
-DGPS used/not used
-ECDIS malfunction
installation setup
-ENC compilation errors (e.g., datums)
-chart (errors, omissions, out-dated)
-survey errors
-human error

Front 80

Describe the US Navy Policy concerning ECDIS.

Back 80

The CNO issued a directive in 1998 calling for a transition of the entire fleet from paper based chart to electronic charting by 2007 (now 09).

Front 81

What is the datum enforced for ECDIS?

Back 81

WGS-84

Front 82

What are the ECDIS functional requirements?

Back 82

-Route planning
-Route monitoring
-Automatic grounding avoidance
-Recording: BLACK BOX
-Tests, alarms, and indications
-Back-up arrangements required

Front 83

Difference between ECS and ECDIS.

Back 83

ECDIS is legally approved, has adequate coverage and updating capability whereas ECS is just any chart.

Front 84

Difference between ECDIS and ECDIS-N.

Back 84

ECDIS is for civilian use and uses ENC.
ECDIS-N is for Navy use and uses DNC (charts prepared by NGA)

Front 85

What are five military uses of GPS?

Back 85

1. Navigation
2. Surveying
3. Target acquisition and destruction
4. Missile Guidance Systems (JDAM, Tomahawk III, JSOW)
5. Data Collection
6. Integration with INS for High Dynamic
7. Environmental Studies
8. Search and Rescue Ops

Front 86

List five civil applications of GPS

Back 86

1. Space shuttle
2. Air navigation
3. Static positioning/timing
4. Land Navigation
5. Maritime navigation
6. Search and Rescue

Front 87

What are 2 distinct techniques used to prevent unathorized use of PPS?

Back 87

1. Selective Availability
2. Anti-spoofing

Front 88

What is anti-spoofing?

Back 88

A technique designed to protect against spoofing (imitation) and unathorized use by encrypting the P code.

Front 89

What is selective availability?

Back 89

The intentional alteration and degradation of GPS accuracy. It is controlled by the MCS and requires Presidential order to invoke.

Front 90

What are some of the primary sources of errors in GPS that are difficult to eliminate?

Back 90

1. Ionospheric and atmospheric delays
2. Small deviations with atomic clocks
3. Math errors with receiving units
4. Satellite signals taking a "circuitous" path to the receivers
5. Geometry between the receiver and satellites

Front 91

What is the Figure of Merit and what is the most accurate and least accurate FOM?

Back 91

Receivers use a "figure of merit" for a general indication of fix accuracy.
FOM1 is the most accurate and FOM9 is the least.

Front 92

What is SPS?

Back 92

Standard Positioning Service: available to all GPS users.

Front 93

What is PPS?

Back 93

Precise Positioning Service: developed primarily for military use which is more accurate and protected (P code)

Front 94

How many line of position do you need for a 2-D fix?

Back 94

3

Front 95

How many LOPs are needed for a 3-D fix?

Back 95

4

Front 96

Where is MCS?

Back 96

Colorado Springs, CO

Front 97

How do you evade from dangerous semi-circle?

Back 97

1) Bring the wind on the starboard bow (45° rel) and hold it there.
2) Make as much headway as possible.
3) If the wind veers (rotates clockwise), change course to hold wind on the starboard bow.
4) The tropical cyclone will pass astern.

Front 98

How do you evade from less-dangerous semi-circle?

Back 98

1) Put the wind on the starboard quarter (130° rel).
2) Make as much headway as possible.
3) If the wind backs--ship is in the less dangerous semi-circle. If it veers—ship is in the dangerous semi-circle.
4) The storm cyclone will pass astern.

Front 99

How do you evade on the storm track?

Back 99

1) Bring wind to the starboard quarter (160°) and maintain course.
2) Run for the navigable semi-circle.
3) If wind direction maintains or veers clockwise slowly, ship is still in the path of the storm.
4) If wind backs (counterclockwise), ship is in less dangerous semi-circle.

Front 100

What is the most important rule of tropical storm evasion with respect to the storm circle?

Back 100

NEVER cross the T. You must be more than 300NM ahead of the storm.

Front 101

What is a weather front?

Back 101

A transition zone between air masses of different densities caused by temp. and humidity differences.

Front 102

What is an air mass?

Back 102

An extremely large body of air whose temp. and humidity density are fairly similar horizontally for a given attitude.

Front 103

What does cold air do as warm air rides up and over cold air?

Back 103

Heavier, more dense cold air retreats slowly, producing widespread clouds and precip.

Front 104

What are plain voice synoptic messages?

Back 104

Messages issued by the ship:
1st indication of tropical cyclone or unusual or hazardous weather

Front 105

What is frontogenesis?

Back 105

The generation or intensification of a front. Occurs when warm air converges onto colder air. The rise of the front's power.