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Boasun 02-26-2010 09:49 PM

Navigation Questions. Can you do them?
 
1. As we ask these questions, lets see if we can stay away from all charts but the universal chart.
2. These are for your edification, so give a try and you may suceed.

A. Convert the following true bearings to relative bearings of a ship who is steering 302; 009, 158, 328.










Hint: R - S = T

jaschrumpf 02-26-2010 10:30 PM

Quote:

Originally Posted by Boasun (Post 574629)
1. As we ask these questions, lets see if we can stay away from all charts but the universal chart.
2. These are for your edification, so give a try and you may suceed.

A. Convert the following true bearings to relative bearings of a ship who is steering 302; 009, 158, 328.

Hint: R - S = T

Your formula works out to:

R = T + S

However, the army.mil site says the equation is:

RB + SH = TB or

RB = TB - SH

RB = Relative Bearing
SH = Ship's Heading
TB = True Bearing

Why the discrepancy? Am I missing something?

tager 02-26-2010 10:46 PM

I don't get the question in the OP. I just head for the buoys, what could go wrong?

SeanConnett 02-26-2010 10:48 PM

Ships Steering 302 True
True Bearing 009 - Relative Bearing 067
True Bearing 158 - Relative Bearing 216
True Bearing 328 - Relative Bearing 026

Boasun 02-26-2010 10:57 PM

Quote:

Originally Posted by jaschrumpf (Post 574644)
Your formula works out to:

R = T + S

However, the army.mil site says the equation is:

RB + SH = TB or

RB = TB - SH

RB = Relative Bearing
SH = Ship's Heading
TB = True Bearing

Why the discrepancy? Am I missing something?

The discrepancy is from not checking my books first before I wrote the question.
R + S = T or as you said: RB + SH = TB

Must have been a mental lapse from deminta or something...
But I did get people to start thinking...
And when I am teaching I do put errors on the board to see if my students are awake and have studied. But it wasn't suppose to happen this time.:rolleyes:

scraph 02-26-2010 11:10 PM

009T is 67R (forward the starboard beam)
158T is 216R (port quarter)
328T is 26R (off the starboard bow)

The army.mil site is correct. What you want to do with the given information is: TB - SH = RB. If the result is negative, you can either consider it an angle towards port (clockwise) or you can add 360 to normalize it to a standard 0-360 angle.

Boasun 02-27-2010 12:05 AM

The Difference in latitude, between two points at 39W Longitude, is 313'; What is the distance in Nautical Miles?

SeanConnett 02-27-2010 12:34 AM

I'm going to say 3.21NM.

jjablonowski 02-27-2010 08:57 AM

193 nm

jrd22 02-27-2010 10:18 AM

I agree with jja above. 193NM


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