AZIMUTH TABLES at Sea OPTION

Azimuth Tables at Sea Option: Instead of calculating the azimuth, you can choose to use the azimuth tables, often referred to as ABC tables.

On this page, you will find an explanation and an example of how to use these tables. Moreover, you can find:

FOUR EXERCISES OF THE AZIMUTH TABLES WITH SOLUTIONS

LA ROCHELLE EXERCISE OPTION TABLES WITH SOLUTION

While traditional printed tables offer reliability, digital tools like our scientific calculator provide convenience and speed.

The primary focus of our website is to offer guidance on the precise calculation of the Line of Position (LOP).

Azimuth Tables at Sea Option: AZIMUTH (Zv)

Azimuth is a mathematical concept used in navigation and surveying to describe the direction of a point relative to a reference direction, typically north.

It is usually measured in degrees, clockwise from north, and ranges from 0° to 360°.

Azimuth Zv: counted from the north cardinal point, from 0° to 360° (clockwise)

Azimuth Tables at Sea Option:

Introduction azimuth tables

Technique used: azimuth by time

Hence, after finding the calculated height, the azimuth Zv must be found to within half a degree.

My tables work on the same principle as the classic and ancient ABC tables. They apply to all celestial bodies and are timeless. The limits of use are up to a maximum latitude of 68° and a declination of 68°. You can download and print them for free from this page.

Firstly, the tables I present are slightly larger than the classic azimuth tables, as the reading is always from top to bottom and not from top to bottom and bottom to top, a technique used to reduce the amount of sheets but which can sometimes be tedious to use.

I do not see any other simple method for explaining azimuth tables other than by example.

Furthermore, on this page, you will find an example of how to calculate the azimuth with the tables

Undoubtedly using the azimuth tables can be a bit laborious at first, but after completing the exercises and practicing again, you will quickly become accustomed to them.

In fact, you may find that you become more proficient with the tables than with using a scientific calculator to calculate Zv.

Moreover, the clarifications presented in the margins of every table sheet are very beneficial, particularly after an extended period of non-utilization.

Azimuth Tables at Sea Option

worksheet for the tables

Azimuth Tables at Sea Option: Part I and Part II, A Quick Overview

(L)atitude

(D)eclination

(P)olar angle

Part I

INPUT:

P and L → lc

P and D → dc

OUTPUT:

lc and dc → zc

Z = acute or obtuse

With these two elements, we proceed to part 2 of the tables

Part II (two volumes: acute and obtuse)

INPUT:

L et zc. (From Part I)

pages 0° to 90° acute (From part I)

OR

pages 90° to 180° obtuse (From Part I)

OUTPUT:

Z

Then transform Z to Zv (True azimuth) using the tables in the right margin, which can be found on each page in Part Two.

complementary information:

lc, dc and zc do not have any specific meaning in navigation but are used only for these tables.

Z is the azimuth between 0° and 180°, while Zv is the true azimuth between 0° and 360°

The tables have been calculated using the following formulas:

Azimuth Tables at Sea Option:

explanation through an example.

Azimuth tables: part 1

(L)atitude = 12° N

(D)eclination = 17° S

(P)olar angle = 10° NW

(the Northern Hemisphere), sun in the West

(Do not confuse it with West longitude.)

Find Zv with azimuth tables

You also find this page see below

Page P = ( 8 to 14°)

P and L → lc = 1,21

P and D → dc = 1,76

In the right margin of each page in Part 1 are the two tables below

We no longer use the rule of signs but same name or not same name !!!

all values will always be positive

In our example:

L et D: NOT SAME NAME

(L = North et D = South)

P < 90°

Conclusion:

zc = lc + dc

(1,21 + 1,76 = 2,97)

Z = obtuse

(between 90° et 180°)

Next, we go to part 2

Azimuth Tables at Sea Option:

Azimuth tables: part 2 (Two volumes)

Note that the acute section ranges from 0° to 90° degrees, while the obtuse section ranges from 90° to 180° degrees.

With latitude L = 12° N and zc = 2.97 we obtain Z.

( Z is obtuse in our example)

In both cases (acute and obtuse), the horizontal line of the latitude 12° N displays somewhere the value zc = 2.97.

Therefore, disagreeably, mixing acute and obtuse angles is where we easily make a mistake (see below)!

acute

obtuse

Z is therefore 161°

But we need to find Zv (modern notation of 0° – 360°)

Also, in the right margin of each page in Part 2 are the two tables below

Avec Z = 161° et P = NW

Zv = 360° – Z

Zv = 360° – 161° = 199°

Azimuth Tables at Sea Option:

Once you grasp the concept of these azimuth tables, proceed to the four exercises utilizing them.