SPECIMEN EXAMINATION FOR SECOND MATE 



33 



If the co-ordinates on a great circle 

 course are transferred from a gno- 

 monic chart to a Mercator chart and the 

 lines connecting them drawn, what is 

 the appearance of the great circle 

 course on the Mercator Chart? 



How should charts be kept corrected? 

 What precautions are necessary when 

 charts have laid unused for a lengthy 

 period after the date of issue? 



If a vessel has laid oflF a great circle 

 track and has departed from the track 

 through bad weather or lack of obser- 

 vations, should she attempt, when her 

 position is determined, to get back on 

 the original track laid down or work 

 out a new course from her determined 

 position? 



A vessel on course 000° sights a light 

 vessel dead ahead at a distance of 10 

 miles. What course should she set to 

 pass the light vessel one mile off her 

 port side? 



What information is provided by the 

 Daily Memoranda? 



Is the water ever shallower than in- 

 dicated on a chart? Explain. 



In approaching land, what scale chart 

 should be used? 



Name the reference planes of sound- 

 ings used on charts and state how you 

 would determine the reference plane 

 when consulting a chart. 



What precautions would you take 

 when transferring positions from one 

 chart to another? 



What information is contained in the 

 Coast Pilots? 



How is the latitude and longitude of 

 a particular point on a Great Circle 

 chart determined? 



How would you know of the issuance 

 of new editions of Hydrographic Office 

 charts in order to replace the old cor- 

 rected charts aboard ships? 



Are parallels of latitude straight lines 

 on a polyconic chart? Explain your an- 

 swer. 



Explain the limitations on the use of 

 middle latitude sailing when crossing 

 the equator. 



In taking a vertical sextant angle, 

 what care is required if the object ob- 

 served is situated far inland from the 

 shore? 



State three methods by which, with- 

 out obtaining the precise position, the 

 navigator may assure himself visually 

 that he is clear of any particular dan- 

 ger. 



A vessel desires to make good a 

 course of 100° and a speed of 9 knots 

 through a current setting NE. True 



with a drift of three knots. 



Required: The course and speed re- 

 quired to accomplish this. 



What precautions should be taken 

 when obtaining the position of a ship 

 by means of a "bow and beam" or 

 "four point" bearing? 



Why should bearings of near objects 

 be used in preference to objects farther 

 away, even though the latter may be 

 more prominent? 



What caution should be obser\'ed in 

 "homing" on the bearing of a light- 

 ship's radio beacon signal? 



Why is a correction necessaiy in 

 plotting on a Mercator chart bearings 

 obtained through the use of a radio 

 direction finder? 



What preparation would you make 

 when planning to enter a strange port? 



A vessel hears a radio distance find- 

 ing signal from a light vessel and 10 

 seconds later hears the sound signal. 

 What is her distance from the light ves- 

 sel? 



What measures should be taken to 

 check the accuracy of direction finder 

 bearings? 



When taking radio direction finder 

 bearings off a coast with islands be- 

 tween your ship and the shore transmit- 

 ter, what care would you exercise? 

 Why? 



Describe briefly how ocean station 

 vessel's radio beacons may be located 

 on the chart. 



When a vessel equipped with a radio 

 direction finder hears a distress signal, 

 what measures should be taken? 



What factors must be considered in 

 obtaining radio direction finder bear- 

 ings on a station broadcasting enter- 

 tainment programs? 



How is a radio direction finder on 

 board ship calibrated for errors caused 

 by electrical conductors nearby? 



How are bearing errors caused by 

 nearby electrical conductors corrected 

 on board ship? 



What is the meaning of the following 

 information taken from the radio bea- 

 con chart for the stations indicated? 



I San Francisco L.S. 314 (3-6). 

 II Farallon314 (3-6). 

 Ill BonitaPt. 314 (3-6). 



How is "night effect" usually mani- 

 fested in radio-direction finder bear- 

 ings? 



Why is night effect unusual when a 

 vessel obtains a bearing from a position 

 less than 50 miles from the radio bea- 



