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Flashcards in Exam 4 Deck (115):
1

What is the largest circle that can be draw on the surface of a sphere and the shortest distance along the surface between any two points?

A great circle

2

The point of greatest latitude along a great circle track is the

Vertex

3

What does a nautical chart represent?

Part of the spherical earth on a plane surface

4

Nautical charts are found in what two formats?

Paper and electronic

5

Name for things a chart shows

Depth of water, Shoreline, TOpographic features, aids to navigation

6

What helps a navigator be knowledgeable of the local area and to avoid possible dangers?

Navigational chart

7

What are four uses of a navigational chart?

Plot courses, determine position, determine navigational options, determine depths or “soundings“

8

______________ Is the process of transforming the earths curved surface onto a flat surface.

Chart projection

9

What happens to a curved surface when transferred to a flat surface?

It will be distorted

10

What are the type of chart projections we will be concerned with?

Mercator, Conic and polyconic projection, Lambert conformal projection, and gnomonic projection

11

Which projection is most frequently used by Mariners?

Mercator

12

Mercator projection is classified as a _______________, And normally tangent to the earths equator.

Cylindrical projection

13

How do rhumb lines plot?

In a straight line.

14

___________ is a line that makes the same oblique angle ( not a multiple of 90*) with all meridians.

Rhumb line

15

A rhumb line is a ___________ curve on the earths surface.

Loxodromic

16

Mercator charts are constructed using what to determine spacing of parallels?

Meridional parts

17

What is a meridional part equal to?

Length of one minute of longitude at the equator.

18

Points on the earths surface are transferred to a tangent cone.

Simple conic projection

19

A series of tangent cones are used to project points on the earths surface.

Polyconic projection

20

A secant cone for a conic projection with 2 standard parallels is a

Lambert conformal projection

21

A straight line on a lambert conformal projection represents an

Approximate great circle

22

A projection where points are projected geometrically from the center of the earth.

Gnomonic projection

23

A gnomonic chart is referred to as a

Great circle chart

24

A ratio of distance on the chart to the actual distance represented on the earths surface.

Scale

25

What are the four chart scale categories?

Sailing charts (1-600000 or greater) voyages
General charts (1:150000-1:600000) coastwise
Coastal charts (1:50000-1:150000) entering or leaving bays
Harbor charts (1-50000 or less) harbors and narrow waterways

26

What is N0S?

National ocean service, a sub agency of in NOAA, which publishes charts covering coastlines and adjacent areas of the United States and its possessions

27

What is NGA?

National geospatial intelligence agency, which publishes charts covering the rest of the world. Formerly named NIMA and DMA.

28

Chart accuracy depends upon

Hydrographic surveys and weather

29

Updates or needed corrections to a chart or posted through

Notice to mariners

30

How often are notice to mariners posted?

Weekly, tracked through 52 weeks of the year and labeled as “week number/year”

31

A reference book used to determine data on a chart is

Chart number one

32

The height of water that is printed on a chart based on a vertical reference points such as mean lower low water is the

Chart datum

33

Heights of objects usually given and Heights above

Mean high water

34

The date a chart was first printed, at the top center of the chart

First edition

35

Date printed in the lower left corner of the chart which contains notice to mariners up to that date.

New edition

36

What contains corrections from notice to mariners between new edition and date of revised chart?

Revised print

37

What contains limit of corrections and is primarily the same chart as the last new Edition also containing the last Epoch of magnetic variation?

Reprint

38

The maximum distance at which the curvature of the earth will permit a light to be seen from a particular height of eye without regard to the luminous intensity of the light is

Geographic range

39

What are two ways to determine geographic range?

By using the geographic range table in the light list, or by computing the formula.

40

What is the formula to compute geographic range?

1.17 Times the square root of height 1+1.17 times the square root of height 2

41

The maximum distance at which a light can be seen under existing visibility conditions is

Luminous range

42

What takes no account of the elevation of the light, the observers height of eye, the curvature of the earth, or interference from background lighting?

Luminous range

43

The maximum distance at which a light can be seen in clear weather is defined by the international visibility code (meteorological visibility of 10 nautical miles)

Nominal range

44

ATONS

Aids to navigation

45

ATONS are also referred to as

Navaids

46

ATONS assist navigators by marking

Prominent features in navigable waters

47

In the United States aids to navigation are maintained by who?

US Coast Guard

48

Aids to navigation can help Mariners find

Safe water, anchorages, information of the area.

49

Name some types of navaids

Light houses, buoys, ranges, placards, radar transponders, shore lights, bridge lights

50

Lights may be

Fixed or floating

51

Prominent lights are usually placed

At Harbor or port entrances and isolated dangers

52

What are lights good for?

Determining fixes, and are costly and becoming highly automated

53

Lights on docs, peers, buildings, are used to assist mariners into

A port

54

How are buoy lights powered?

By battery or solar

55

What do red bridge lights indicate?

Peers and other parts of the bridge, or show that drawbridges are closed

56

What do green lights Mark?

Shows the drawbridges are open, and mark the centerline of the Navigable channel thru fixed bridges

57

White bridge lights

Draw attention to the navigational obstacle

58

IALA

International Association of lighthouse authorities

59

IALA promotes uniformity among different countries in there

Lighthouse and buoyage systems

60

Rangers are used to

Steer a desired course

61

Ranges have both day marks and night marks. What are they?

Day marks are vertical striped boards, and night marks are colored lights

62

Day marks are represented by what on a chart?

Three letters

63

K represents a

Square or rectangular board

64

The second letter in a Daymark represents the

Outside stripes

65

The third letter in a Daymark represents the

Inside stripe

66

Buoys are

Floating aids to navigation

67

Buoys are usually used to mark

A channel, shoal/obstruction, Anchorage

68

Name five types of buoys.

Lateral marks, isolated danger marks in cardinal marks, safe watermarks, special marks, information/regulatory marks.

69

A beacon is a

Fixed, not floating aid to navigation

70

A beacon with lights is called a

Lighted beacon

71

Unlit Beacons are called

Day beacons

72

Lateral marks should be passed

To port or starboard

73

The u.s is in IALA-

B

74

IALA-B follows

Red, right, returning theory

75

IALA-A reverses the

Colors, not the shapes

76

A nun buoy is shaped like a

Cone

77

A can buoy is shaped like a

Cylinder

78

What are the two types of isolated danger marks?

Isolated danger mark’s - US
Cardinal marks – international

79

Isolated danger marks do not indicate the direction in which to pass, but

Which area to avoid

80

The shapes for an isolated danger mark will be

Two black Spheres

81

The lighting for an isolated danger mark will be

Two flashes

82

Isolated danger mark will be black with horizontal

Red bands

83

What do cardinal marks indicate?

The deepest water near a point of interest lies in the direction named by the mark, the safe side to pass a danger, are always to the named side of the point of interest, and will always have yellow/black bands, two black cone top marks, and white light with rhythm shown.

84

Uninterrupted flashing equals

North quadrant

85

Three flashes per group equals

East quadrant

86

Six flashes per group plus a long flash equals

South quadrant

87

Nine flashes per group equals

West quadrant

88

Traffic separation scheme marks, spoiled ground marks, cable or pipeline area marks, military exercise zone marks, recreation zone marks, or oceanographic data acquisition system buoys are examples of

Special marks

89

What color are special marks?

Yellow, and any top Mark will be a yellow X (top marks are optional)

90

Special Mark lights will always be

Yellow, usually with a fixed or slow flash characteristic

91

What has an alternating blue and yellow flashing light, and put in place until the lateral or cardinal buoy is deployed?

Emergency wreck buoy

92

What are the five types of sound signals?

Diaphones, horn’s, sirens, whistles, bells/dong’s

93

A sound produced by slotted piston that is move back-and-forth by compressed air, often known as a two tone signal is a

Diaphone

94

Sound produced by a disc diaphragm operates pneumatically or electrically is a

Horn

95

Sound produced by disc or cup shaped rotor operated pneumatically or electrically is a

Siren

96

Sound produced by compressed air emitted thru a slot into a cylindrical bell chamber is a

Whistle

97

Sound produced by a mechanical hammer

Bell/gong

98

Are sirens used in the u.s. ATONS?

No

99

Red buoys have

Even numbers

100

What color buoys have odd numbers?

Green

101

The buoys farthest out to sea have what numbers?

Lowest

102

Buoys that are not solid green or red are not numbered and therefore will be

Named by a letter or letters

103

Lights on red or green lateral buoyswill be

Occulting, isophase, or regularly flashing less than 50 per minute

104

A quick flashing buoy (more than 50, less than 80) is marking

Caution or danger

105

A buoy flashing a Morse code letter appx 8 times a minute is a

Safe water buoy

106

Red right returning

Clockwise inland waters coming from seaward

107

If traveling in a clockwise direction what buoys do you keep between you and land?

Red

108

A vessel is proceeding seaward if traveling

Counter clockwise

109

An inland waterway that runs along the Atlantic and gulf coasts from New Jersey to Mexico is an

Intercostal waterway

110

An enroute sailing direction is

More detailed and 37 publications describing coastline, ports and harbors

111

Planning guide is a zoomed out version

With 10 publications describing ocean basins

112

Coast pilots is published by

National ocean service
9 pubs

113

Coast pilots info includes

Local practice, pilotage, anchorages, comms, weather, routing

114

Light list published by

Coast guard

115

List of lights published by

NGA