hi guys today I will be solving a compass error question but I will be using the amplitude method to do so and the celestial body will be son as an example all right so let's start with the question the question says is 23rd of September 1992 and the son was the rising it rose bearing Sun was rising so I will write rising here bearing 0 9 4 degrees compass or the compass bearing of the Sun is given to you your D our position how your dead reckoning position was 0 degrees latitude that is equator and 1/2 0 degrees 27 its worst loss you're down with children you have chronometer Shyam should 0 1 ass 54 minutes 0 seconds if chronometer error was 3 minutes 12 seconds fast and variation was two point seven degrees west you have to find the deviation now you have to use the amplitude method not the azimuth method so let's solve the ambiguity of the chronometer time first you have to find out what is your correct GMD time so your chronometer time given to you is 154 Minzy roe seconds that could mean one are in the morning or one in the afternoon so you just add 12 hours to the hours here and give it another possibility so it could be 1 5400 or 13 5400 apply your error your error is 3 minutes 12 seconds and it's fast whenever the error is fast you will subtract it so subtract the same error in both the cases so you get two possibilities of the GMT time one hour 50 minutes 48 seconds and 13 hours 50 minutes 48 seconds so how do you find out which is the correct GMT so for that you have to find out your local mean time or your LM T so do that you apply your longitude in time correction Li T which you get by dividing longitude by 15 your longitude is 1/2 0 degrees 27 minutes divided by 15 and you will get 8 hours 0 1 minutes 40 seconds whenever your longitude is west subtract it from the GMT to get your LMT longitude west GMT is the best that means GMT is more than the LMT alright so again you get two cases of the local mean time one is 17 hours 49 minutes row seconds and the other is Phi was 49 minutes you seconds so how do I know which is the LMT well the hint is given to me in the question itself that the Sun was rising locally if the Sun is rising the local meantime on my ship has to be the morning time it cannot be rising at 1700 hours in the evening so this becomes your own possibility so if this is the correct GM LMT my date is 23rd of September here and then this date is also to the 3rd of September this is the same day it's just it has behind from 1300 hours so my current GMT will be 23rd of September 13 hours 15 minutes 48 seconds now in this point of time just make a note that do not use the LM T time you have to use the GMT time LM T time is calculated only to find out or determine which is the correct GMT time find out the correct GMT time and then use the GMT time for the rest of the question all right don't use the LM T time like some students do so if the GMT time is 23rd of September 13 hours 15 minutes 48 seconds I only needed this time to find my declination for 23rd September 13 hours okay so let's go into 23rd of September nautical Almanac all right so 23rd is somewhere here let me raise the rest of the stuff so that you guys don't get confused so 23rd of September is somewhere here this is the date on top this is the Sun so my GMT my correct G and the time I need it for is 1300 hours right 1300 this is 1300 hours so my declination for the Sun will be somewhere around here zero degrees 17 point eight minutes south my D value is one and my declination is increasing by the next star so these are the some of the things I know don't sigh note down my D value of one I caught my declination value and then I will go into the increments page for 50 minutes and 48 seconds because this declination values for $1,300 the correction value will be for 50 minutes and 48 seconds from the increment space so that I can get the corrected declination for 13 hours 50 minutes and 48 seconds which is my required GMT so I'll go into the increments page for 50 minutes and 48 seconds 15 minutes and 48 seconds will be somewhere here so my D value is 1 so this is 15 minutes and D value is 1 and my D correction value will be zero point 8 all right then go back I apply this 0.8 correction I have caught my decoration is 0.8 which I will add because my declination while he was increasing as I went from $1,300 to $1,400 so I get my declination corrected as 0 degrees 18 point 6 minutes so then I simply have to put it in the formula here sine am video D cosine of definition divided by cos of latitude sine of declination is the correct declination I calculated the latitude is of course given to mean the question is 0 which is the equator so I get my sign amplitude equals zero point zero zero five four one so I take sine here and sine inverse becomes of this value gives me my amplitude value of 0.3 at this point happening my amplitude now here is the tricky part trying to remember okay this is the tricky part so you will name it first whether is rising or setting if it's rising its east if it was setting you would have named it rest and this part is comes from the declination so your declination is south so your name itself so it will be east zero point three south so what does that mean that means this is not this is East and this is south then zero point three South means from the east going down 0.3 so this is zero nine zero zero point three would be zero nine zero point three and that's why your true bearing is zero nine zero point three all right so this is the tricky part how you name it you first name it based on whether it's rising or setting and then secondly you name it as per the declination then the compass being given to you and the question is 0 9 4 degrees so zero nine four minus zero nine zero point three will give you the compass error again the compass is more so error will be worst if the compass is best error is worst so three point seven degrees west your variation is two point seven degrees west divide difference between not divided so a difference between the two will give you the deviation is 1 degree west and let me show you conceptually what this means so your true bearing is zero nine zero point three right your compass bearing was zero nine four degrees so this total angle is your compass error which is three point seven degrees west compass is lying on the West I'll change the current now then your magnetic is your variation is two point seven degrees west so the magnetic a variation is the angle between the true and the magnetic where your magnetic is lying on the token so this angle here is two point seven degrees west therefore your deviation which is the angle between the compass and the magnetic well you see where the compass is bank compasses line to the west of magnetic this angle becomes three point seven minus two point seven which is 1 degree west alright so understand it conceptually as well so whenever you calculate compositors make sure you also find out the value conceptually find out the angle between the values all right so I hope this question was useful for you to learn how to find the compass error using the amplitude method especially when the Sun is the celestial body let me know what you thought about this video guys I'll see you soon my next video bye