How do you use the altitude intercept method in navigation?

Altitude Intercept is calculated using ho from Section I, and hc from Section IV. It is a measure of the distance from the Assumed Position to the Line of Position. To determine the direction of the Line of Position, we investigate if ho is greater than hc.

How do you find the intercept in navigation?

If the true zenith distance is greater than calculated zenith distance, then the observer is further away from the geographical position of the celestial body compared with the DR position, and the intercept is called AWAY.

Why do we use the intercept method?

For star sights, intercept method is preferred for calculations. We already know the DR position of the ship. With these values we can plot the position line on the chart. We just need to know from where to draw this position line.

What is the most known method for obtaining a celestial line of position?

The Marcq St. Hilaire Method is the classic way of undertaking a celestial position fix. You measure the altitude of 6 celestial bodies at sunrise or sunset.

What is intercept terminal point?

The difference between the two is known as the Intercept. The closest point on this circle is known as the Intercept Terminal Position (ITP) and the line representing the circle at that position is called a Position Line.

Which publication where had designed primarily for use with the Marq St Hilaire intercept method of sight reduction?

A method of sight reduction proposed by Captain (later Admiral) Marcq de Blond de Saint-Hilaire in an influential paper entitled ‘Calcul du point observé’ published in 1875 in the French Revue maritime et coloniale.

What is intercept in navigation?

In astronomical navigation, the intercept method, also known as Marcq St. Hilaire method, is a method of calculating an observer’s position on earth (geopositioning). The intersection of two or more such lines will define the observer’s position, called a “fix”.

What is the two intercept method?

The Slope-Intercept Form is essentially a special case of the Point-Slope Form. It’s said that two points determine a line. That truism is used to quickly sketch a line if its equation is given in the Two Intercept-Form ax + by = c. We get the y-intercept by setting x = 0 and solving for y: by = c, y = c b .

What is the importance of sight reduction in celestial navigation?

This method is a practical procedure to reduce celestial sights with the needed accuracy, without using electronic tools such as calculator or a computer. And it could serve as a backup in case of malfunction of the positioning system aboard.

https://www.youtube.com/watch?v=PI3wtc-C_CY