IMO STANDARD MARINE COMMUNICATION PHRASES (SMCP)

Activity – You are transiting a strait and passing a VTS reporting point. Write down the phrases that you will use to communicate the required information to the VTS. Use the IMO Standard marine communication phrases (SMCP).

SMCP stand for – IMO STANDARD MARINE COMMUNICATION PHRASES

Why we need SMCP (IMO STANDARD MARINE COMMUNICATION PHRASES)?

The Standard Marine Communication Phrases (SMCP) has been compiled: –

  • To assist in the greater safety of navigation and of the conduct of the ship,
  • To standardize the language used in communication for navigation at sea, in port-approaches, in waterways, harbours and onboard vessels with multilingual crews, and – to assist maritime training institutions in meeting the objectives mentioned above.
  • Please note – These phrases are not intended to supplant or contradict the International Regulations for Preventing Collisions at Sea, 1972.

IMO STANDARD MARINE COMMUNICATION PHRASES

Step 1 – Initiation

When it is necessary to indicate that the SMCP is to be used, the following message may be sent:

  • “Please use Standard Marine Communication Phrases.”
  • “I will use Standard Marine Communication Phrases.”

Step 2 – Spelling

To give the correct spelling we use phonetics –


phonetics – SMCP

phonetics – SMCP

Step 3 – Message Notation / format / maker

  • (i) Instruction
  • (ii) Advice
  • (iii) Warning
  • (iv) Information
  • (v) Question
  • (vi) Answer
  • (vii) Request
  • (viii) Intention

Step 3B – Distress, urgency, and safety signals

  • MAYDAY to be used to announce a distress message
  • PAN – PAN to be used to announce an urgency message
  • SÈCURITÈ to be used to announce a safety message

Step 4 – Response is started with and then your message

  • Affirmative
  • negative
  • Stand by
  • No information.

Standard organizational phrases

“How do you read (me)?”

  • “I read you …
    • bad/one with signal strength one (i.e. barely perceptible)
    • poor/two with signal strength two (i.e. weak)
    • fair/three with signal strength three (i.e. fairly good)
    • good/four with signal strength four (i.e. good)
    • excellent/five with signal strength five (i.e. very good)
  • When it is advisable to remain on a VHF Channel/frequency say: “Stand by on VHF Channel … / frequency … ”
  • When it is accepted to remain on the VHF channel/frequency indicated, say: “Standing by on VHF Channel … / frequency … ”
  • When it is advisable to change to another VHF Channel/frequency, say: “Advise (you) change to VHF Channel … / frequency … .” “Advise(you) try VHF Channel .. / frequency… .”
  • When the changing of a VHF Channel/frequency is accepted, say: “Changing to VHF Channel … / frequency … .”
  • correction / readyness and Repetition
    • Example – “My present speed is 11 knots – mistake.
      • Correction, my present speed is 12, one-two, knots.”

Compass Error Calculation by Azimuth of Planets

Let’s learn how to calculate compass error by the Azimuth of any planet. We will understand this with the help of an easy example.

Sample calculation (Azimuth- Planets):


On 06 May 2006 at 22h20m 10s UTC, a vessel in position 48°00’N 050°00’E observed Mars bearing 327° by compass. Find the compass error. If variation was 4.0° East, calculate the deviation.


GHA Mars (06d 22h): = 089° 55.7′
Increment (20m 10s): = 005° 02.5
v (0.9)             =     00.3
GHA Mars: = 094°58.5′


Longitude (E):  (+) 050° 00.0′ (plus-since longitude is easterly)
LHA Mars:                 144° 58.5


Declination (06d 22h): = N 024° 18.6
d (0.2): = 00.1 (D correction)
Declination Mars: = N 024° 18.5

Now we will FIND – P and use ABC method for further calculations.
P= 1440 58.5 (If LHA 180° P=LHA)
A = Tan Latitude/ Tan P
A = Tan 48° 00′ / Tan 144° 58.5
A = 1.584646985 N (A is named opposite to latitude, except when hour angle is between 090° and 270°).
B = Tan Declination/Sin P
B= Tan 024° 18.5′ / Sin 144° 58.5′
B = 0.787011353 N (B is always named same as declination)
C = A+B = 2.371658338 N (C correction, A+/- B: If A and B have same name-add, If different name- subtract).


Tan Azimuth = 1/(CX Cos Latitude)
Tan Azimuth = 0.6301399
Azimuth = N 32.2° W (Azimuth takes the combined name of C correction and Hour Angle – If LHA is between 0°and 180°, it is named “west”, if LHA is between 180° and 360, it is named “east).


True Azimuth= 327.8°
Compass Azimuth= 327.0°
Compass Error = 0.8° East
Variation = 4.0° East (you can find this in ECDIS when finding compass error onboard)
Deviation = 3.2° West

Determine compass error using the azimuth of a star.

Sample calculation (Azimuth-Stars):


Let’s LEARN WITH AN EXAMPLE –

On 05 May 2006 at 11h00m00s UTC, a vessel in position 04°30’N 010°00’W observed Canopus – bearing 145° by compass. Find the compass error. If variation was 4.0° East, calculate the deviation.


GHA Aries  (05d 11h): 028° 10.7°
Increment (00m 00s): 000° 00.0
(adding +)
GHA Aries: 028° 10.7
Longitude (W): – 010° 00.0′ (minus- since longitude is westerly)
LHA Aries: 018° 10.7


SHA Canopus: 263° 59.0
LHA Canopus: 282° 09.7′

Declination:
S 052° 42.1
P= 360 – 282° 09.7° = 77° 50.3″ (IF LHA>180, P=360-LHA)
A = Tan Latitude/ Tan P
A = Tan 04° 30′ / Tan 77° 50.3
A = 0.016960803 S (A is named opposite to latitude, except when hour angle is between 090° and 270°)

B = Tan Declination / Sin P
B= Tan 052° 42.1′ / Sin 77° 50.3
B
= 1.342905601 S (B is always named same as declination)


C = A+B = 1.359866404 S (C correction, A+/- B: If A and B have same name- add, If different name subtract)


Tan Azimuth = 1/(C X Cos Latitude)
Tan Azimuth = 0.737640253
Azimuth = S 36.4° E (Azimuth takes the combined name of C correction and Hour Angle- If LHA is between 0°and 180°, it is named west”, if LHA is between 180° and 360°, it is named “east”).


True Azimuth= 143.6°
Compass Azimuth= 145.0°
Compass Error = 1.4° West
Variation = 4.0° East
Deviation = 5.4° West

How to find compass error (using Azimuth of the sun).

Required Information –

  • GMT
  • Longitude and Latitude
  • Gyro heading and Compass heading
  • Gyro bearing of SUN (As most probably the azimuth circle will give you Gyro bearing and not Magnetic bearing).

Calculations –

Calculate for Nautical Almanac the GHA of the SUN

GHA (Day and Hour ) : __________

INCREMENT (Minutes) : ___________

Add both you will get GHA of SUN.

Then GHA (SUN) + Longitude (+ if E / – if west) = LHA(SUN)

Leave this information aside we will need it later, Next, we will find DECLINATION of the Sun using Almanac (Days page).

DECLINATION (Day and Hour)

+/- D-Correction ()

With this you will get your DECLINATION.

Now we need to find LHA

If LHA is more than 180 (P=360-LHA ) & If LHA is less than 180 (P = LHA).

A = TAN (LATITUDE) / TAN (P)

When hour angle is between 270 to 090, A is named opposite to latitude.

when hour angle is between 090 and 270 Degree, A is named same as latitude.

B= TAN (DECLINATION) / SIN (P)

B is always named same as declination.

C = A +/- B

If A and B both have same sign then we add them, If they have diffrent sign we substract them and put the sign of the bigger side.

Tan Azimuth = 1/[(C * Cos (Lat)]

Azimuth takes combined name of C and Hour angle – If LHA is between 0 and 180, It is named “West”, If LHA is between 180 and 360, It is named as EAST.

NOW Compare TRUE AZIMUTH with the GYRO AZIMUTH of SUN, the diffrence is your compass error (GYRO).

HOW TO FIND COMPASS ERROR (MAGNETIC). 

Initially check your VESSEL heading in gyro and magnetic for example if gyro heading is 050 and magnetic heading is 054 then you know the difference is 4 , Now when you observe the bearing of the sun using azimuth circle you get Gyro azimuth lets say it is 080 then what will be your compass bearing? It will be 084, Similary to calculate compass error (magnetic) we use Observed Azimuth magnetic and the True Azimuth.