Theory Flashcards
Methods of visual signalling (there are 5)
Flags
Flashing Light
Pyrotechnics
Coloured Lights
Shapes
What does RAM shapes stand for?
Restricted Ability to Manoeuvre
How are the shapes organised to show restricted ability to manoeuvre?
Ball, Diamond, Ball vertically, 1.5M apart
Advantages and disadvantages of flashing light
Advantages
Security
Disadvantages
Weather conditions
Range
Speed of transmission
What flare has a serrated edge and a cross in the centre, and what’s it used for?
Red - emergency: submarine in serious trouble and will surface immediately
What flare has a half serated edge and a circle in the centre, and what’s it used for?
White - submarine coming to the surface or periscope depth
What flare has a smooth edge and a triangle in the centre, and what’s it used for?
Green - submarine attack signal (simulated)
When would you use RAMS?
(There are 4)
- Replenishment at sea
- Flying operations
- Diving and other underwater operations
- Towing
How far apart are ram shapes organised?
At least 1.5m
At night what would you use in stead of RAMS and how would you organise them?
Lights consisting of two red lights and one white. Vertically arranged, 2 metres apart Red - White - Red
Define the man overboard (MOB) lights
During the night display two pulsating red lights, arranged vertically 2 metres apart pulsating at 50-60 ppm
Must be in a visible location.
How would you show you’re Not Under Command (NUC)?
Day and night
By day two black balls arranged vertically at least 1.5m apart.
By night two red lights arranged vertically 2 metres apart.
Define Anchor Shapes and Lights
By day one black ball on the side the anchor is out.
By night two white lights, one on the jackstaff forward, and one on the stern the lower position. The light on the jackstaff must be higher.
Basic rules essential for discipline and security when visual signalling
- No transmission shall be made which has not been authorised by proper authority.
- an immediate answer to a call is essential.
Practices specifically forbidden when visual signalling
(There are 8)
- violation of visual silence
- unofficial conversation between operators
- transmitting the operators personal sign
- unauthorised use of plain language
- use of other than authorised prosigns
- unauthorised use of plain language in place of applicable prosigns or opsigs
- linkage or compromise of classified callsigns and address groups by plan language disclosures
- profane language
What does prosign W mean?
Train your light (your light is unreadable)
Practices to be avoided when visual signalling
- use of excessive beam width or a light larger than necessary
- transmitting at speeds beyond the capability of receiving operators.
Where can we find visual signalling callsigns?
ACP113
What is the double flash procedure?
ZJJ - flashing for understanding the signal and flashing for recording the signal when only one operator is recieving and recording.
What are the two ways of relaying a callsign when calling up another station?
Full call - F239
Abbreviated call - F9
3 principles when transmitting a signal
Accuracy - each character or prosign must be made clearly and distinctly.
Speed - transmitting speed is governed by the capabilities of the receive operator.
Precision - messages must always be transmitted exactly as written
What is the 15 inch light used for?
- Long and medium range daylight signalling
- search and rescue
- ELVA (emergency low visibility approach) for aircraft
What is the 10 inch light used for?
Medium range daylight signalling
Short range search light
What is the 5 inch light used for?
- Medium range daylight signalling
- long range night signalling
- red filter capability
