42 



UNITED STATES COAST GUARD 



20. NAUTICAL ASTRONOMY AND NAVIGATION DEFINITIONS. 



15. Polar distance? 



16. Amplitude? 



17. Diurnal circle? 



18. Sidereal day? 



19. Circle of equal altitude? 



20. Parallel of altitude? 



21. Most probable position? 



22. Greenwich sidereal time? 



Define the term "magnitude" as it is 

 employed in nautical astronomy. 



What is meant when two celestial 

 bodies are said to be in: 



(a) Conjunction; 



(b) Opposition? 



22. SIGNALLING BY INTERNATIONAL CODE FLAGS, 

 FLASHING LIGHT; 

 LIFESAVING, STORM AND SPECIAL SIGNALS. 



What would be indicated by a black 

 or green signal seen floating in the air 

 from a parachute about 300 feet above 

 the water? 



State the meaning of the following 

 hoist in International Code Flag Sig- 

 nalling : 



(a) 



Answering pennant 



E 



(b) (c) 



X T 



2 1 



1st 1st 



repeater repeater 

 



3rd 

 repeater 



When signalling by International 

 Code Flags and using the code flags or 

 answering pennants to indicate a deci- 

 mal point, is the code flag included in 

 determining which repeater or substi- 

 tute is to be used? 



In sending a message to a vessel by 

 Morse Code using flashing light, how 

 would you indicate that the message 

 would be coded from the International 

 Code of Signals? 



Describe how the International Code 

 flags are used to signal the position of 

 the ship expressed in terms of latitude 

 and longitude. 



Name the component parts of a Morse 

 Code message. 



Show exactly how you would signal 

 the following times, using the Interna- 

 tional Code flags : 



(a) Five minutes past midnight. 



(b) Six-forty-five p.m. 



(c) Ten o'clock a.m. 



(d) Ten o'clock p.m. 



What signal, that may be transmitted 

 by flashing light, is provided by the In- 

 ternational Rules of the Road to in- 

 dicate that a vessel is in distress and 

 requires assistance from other vessels 

 or from the shore? 



When a vessel in distress in Inter- 

 national Waters requires assistance 

 from the shore, what signals are pro- 

 vided by the International Rules of the 

 Road for her to use? 



What is indicated by an aircraft 

 ciixling a vessel at least once, then 

 crossing the bow close at a low altitude 

 opening and closing the throttle or 

 changing the pitch of the propellers, 

 and then flying away on a particular 

 bearing? 



Describe the procedure for calling an- 

 other vessel, or vessels, using the Inter- 

 national Code flags. 



Describe the procedure for answering 

 flag signals. 



Describe the correct use of the erase 

 sign and show how the erase sign is 

 made in signalling by flashing light. 



For what purpose is the model verb 

 "to glean" printed in all of its forms in 

 the text of the International Code of 

 Signals? 



What is the lifesaving signal indicat- 

 ing, "landing here highly dangerous"? 



