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Flashcards in Exam 3 Deck (40):
1

Sailings is using math to solve for

Courses and distance from one point to another, and point of arrival when point of departure, course, and distances are known.

2

What are the five types of sailings?

1 = plane sailing
2 = parallel sailing
3 = mid latitude sailing
4 = mercator sailing
5 = Great circle sailing

3

When used in sailings, the word departure refers to

East to west distance in miles, or west to east distance in miles

4

One minute of latitude equals

1 mile

5

One minute of longitude

Does not equal 1 mile anywhere except at the equator

6

While navigating off of the equator the difference of longitude between two points, in minutes of longitude

Does not equal the east to west distance in miles

7

Departure is written as what?

P

8

What type of functions are used in sailings?

Natural trigonometric

9

Accuracy in navigation problems is to the nearest

10th of a mile or 10th of a minute of longitude or latitude

10

A 10th of a mile =

608 feet
(6076.1÷10 = 607.61 feet)

11

How many different angles does each group of trig functions contain?

Four

12

All five types of sailings are used to determine

Course and distance

13

Plane sailings is used to find

The difference of latitude and departure

14

Parallel sailings are used to find

Longitude of arrival

15

Mid latitude and Mercator sailings are used to find

Latitude and longitude of arrival

16

Great circle sailings are used to find

The initial course and distance, latitude and longitude of Vertex, and points along the great circle route

17

Plane sailings use simple plane geometry to solve for the parts of a
And assumes that the earth is

Right triangle; flat

18

Why can’t plane sailings solve for difference of longitude?

Because the earth is a sphere

19

C=

Course angle (off 000°/360° or 180°)

20

D=

Distance

21

Parallel sailing was used prior to accurate When it wasn’t possible to determine

Chronometer; longitude

22

Prior to accurate chronometers, ships would run north or south to latitude of destination, then head east or west to the actual destination adjusting course as needed.

True

23

What is parallel sailing mainly used for today?

As a component part of mid lat sailing

24

DLo=

Difference in longitude in minutes

25

In reference to parallel sailings the course will either be

Due West (270°) or East (090°)

26

Mid latitude sailing is a combination of

Plane and parallel sailings

27

With regards to midlatitude sailings, the plane sailing is used to

Find the difference of latitude and departure when we know course in distance, or find a course in distance when we no difference of latitude and departure

28

With regards to mid latitude sailings, parallel sailing is used to

Convert departure to difference of longitude or vice versa

29

The latitude that is used in parallel sailing part of midlatitude sailing is the
Of the latitude of departure and the latitude of arrival

Mean

30

Do not use mid latitude sailing if you

Cross the equator

31

If you are crossing the equator it’s best to use

Mercator sailings

32

In Mercator charts the course is measured by the angle between the

Meridian (longitude line) and the coarse line

33

How is distance measured on the Mercator charts?

With dividers on the latitude scale at the left or right side of the chart

34

One minute of latitude =

One nautical mile

35

Can difference of longitude be used as miles?

No

36

Meridional parts and D-Lo in minutes of longitude are used to

Find the course angle

37

The length of the arc of a meridian between equator and a given parallel on a Mercator chart expressed in units of one minute of longitude at the equator.

Meridional parts

38

The largest circle that can be drawn on the surface of a sphere and the shortest distance along the surface between any two points.

Great circle sailing

39

A great circle on the earth will be any

Meridian and the equatorial belt

40

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

Vertex