Laura Grimm: How Do We Communicate?, July 12, 2022

NOAA Teacher at Sea

Laura Grimm

Aboard NOAA Ship Thomas Jefferson

July 4 – July 22, 2022

Mission: Hydrographic Survey of Lake Erie

Geographic Area of Cruise: Lake Erie

Date: July 12, 2022

Weather Data from the Bridge

Latitude: 42 11.79’ N

Longitude: 080 07.79’ W

Sky Conditions: Few clouds

Visibility: 10+ miles

Wind Speed: 13.9knots

Wind Direction: 245ᵒ E

Lake Temperature: 22.3 ᵒC

Wave Height:  2-4 ft. ***

Dry Bulb:  24.3 C

Wet Bulb:  22.1 C

Relative Humidity: 84 %

(*** As the wave height increases, going up or down stairs is a lot like being on a roller coaster. As the ship moves up on a wave, you feel somewhat weightless. As the ship moves down, the G-forces (gravity) make you feel “heavy”. It is fun – until you run into the wall!)

Science and Technology Log

Standing on the bridge, one hears a lot of radio communication between boats and occasionally the Coast Guard.  The bridge also communicates frequently with the survey technicians via an intercom.  

This made me start to wonder about how the ship communicates in other ways.  Let me tell you, there are many other ways for the ship to communicate other than radio.  One way is via Morse code.   According to Kiddle Encyclopedia, “Morse code is a type of code that is used to send telegraphic information using rhythm. Morse code uses dots and dashes to show the alphabet letters, numbers, punctuation and special characters of a given message. When messages are sent audibly (with sound) by Morse code, dots are short beeps or clicks, and dashes are longer ones.”

Morse code is named after Samuel Morse, who helped invent it. It is not used as much today as it was in the 19th and 20th centuries.  Some people still use Morse code to communicate on amateur radio.  I have a friend who is an amateur radio operator.  He communicates with people all over the world using Morse Code.  (He even signs birthday cards in Code!)  In Girl Scouts, we were encouraged to learn Morse code.  All I remember is the distress code: SOS (. . . – – – . . .). 

International Morse Code chart of letters and numbers

Another way the ship can communicate is with a signal light.  The operator opens and closes louvers in front of the light using the same Morse code dot & dash patterns.

a NOAA Corps Officer closes blinds over a large circular light on a rotating stand
Morse code is still used on ships using lights.

Messages can be relayed via the ship’s horn.  I discussed in a previous post the ship’s alarm signals that indicate a fire or other emergency, man overboard, or abandon ship. However, the ship also has bells and whistles (different types of horns) that can be used for additional communication; these broadcast a message to a wider audience.  There are rules that regulate horn usage in inland and international waters.  These signals can communicate navigation or emergency information – and so much more.

Example: two prolonged blasts followed by one short blast = “I intend to overtake you on your starboard side”

If you are in distress, other ways to communicate include lights; a rocket parachute flare or a hand flare showing a red light; guns or other explosive devises; flames on the vessel (as from a burning tar barrel, oil barrel, etc.); a smoke signal giving off orange-colored smoke; slowly and repeatedly raising and lowering arms outstretched to each side; etc.

Flags are also used to communicate with other ships or people ashore.  They consist of flags and pennants of varying colors, shapes, and markings. The flags have independent meanings; however, when used together they can spell out words and communicate complex messages.  The book International Code of Signals lists literally hundreds of 1-3 flag combinations that mean everything from describing medical conditions of crew members to issues regarding safe maritime travel.  The International Code Signal of distress is indicated by the flags that represent the letter “N” followed by the letter “C”.

two flags representing the letters "N" and "C." The "N" flag is checkered with navy and white squares. the "C" flag has five horizontal stripes: navy, white, red, white, navy.
N C = International Code Signal of Distress
a chart of flags (representing letters) and pennants (representing numerals)
International Flags and Pennants sometimes referred to as the Nautical Alphabet.

Something else you should know about communicating on a ship (or as an airplane pilot), each letter is represented by a word.  A = Alfa, B = Bravo, C = Charlie, D = Delta, etc.  To learn more, see the International Flags and Pennants illustration above.

For the little Dawgs . . . (and older)

Q: Where is Dewey today?  Hint: People on the ship use these to communicate.

Dewey the beanie monkey is tucked into a cubby storing flags and penants (close-up)
I’m not sure where you are, Dewey!  But it looks like you have found a very colorful playground.

A: Dewey is in the signal flag storage area.

Dewey the beanie monkey is tucked into a cubby storing flags and penants (wide view)
Signal flag storage area

The radio call sign of NOAA Ship Thomas Jefferson is WTEA (Whiskey Tango Echo Alfa).  Do you see the flags flying from our mast in the pictures below?  The triangle pennant above the flags that indicate our radio call sign is called our commissioning pennant- indicating a government vessel (NOAA ship) in commission.  The triangles on this pennant symbolize a concept in navigation called triangulation.  According to Wikipedia, “triangulation is the process of determining the location of a point by forming triangles to the point from known points”.  It is a perfect pennant for a hydrographic vessel.

on the tower of NOAA Ship Thomas Jefferson, we can see four rectangular flags (corresponding to the call sign, WTEA) and one skinny commissioning pennant
Radio call signs for NOAA Ship Thomas Jefferson WTEA (Whiskey Tango Echo Alfa)
four rectangular flags (corresponding to the call sign, WTEA) and one skinny commissioning pennant
Radio Call Sign Flags

Students, I challenge you draw out your name using International Flags.

image of five letter flags in a row
These flags spell out, “GRIMM” (Golf, Romeo, India, Mike, Mike)
image of six letter flags in a row
These flags spell out, “DALTON” (Delta, Alfa, Lima, Tango, Oscar, November)

Click on this link and/or watch the video below for more information about International Flags and Pennants.

International Code of Signal Flags

Ship Joke of the Day 

How do boats say hello to one another?  (They wave!) . . . Or, do they wave their flags?

Personal Log

Speaking of flags, I had very meaningful thing happened today.  I was just hanging out in the bridge.  I like to see how they navigate and steer the ship.  (It is also a great place to bird watch.)  Operations Officer, LT Levano, asked me if I would like to have a flag that flew over the NOAA Ship Thomas Jefferson.  Whenever a flag becomes a bit tattered or torn, they take it down and replace it with a new one.  They usually give the old flag to the Boy Scouts of America for disposal.  This time, however, they gave it to me!  It brought me to tears.  It was a very special moment for me as a Teacher at Sea.

Able Bodied Seaman (AB) Kinnett and ENS Brostowski folded the flag and made the formal presentation.

  • two crewmembers hold an old American flag out by its corners to prepare for folding
  • two crewmembers folding the flag lengthwise
  • one crewmember holds a folded edge while the other folds his side over in right triangles
  • crewmembers folding a flag
  • crewmembers stand holding the old American flag as a folded triangle

Previews of coming attractions:

  • Tonight, is movie night in the lounge.  Word has it that the featured film will be Monty Python and the Holy Grail!  Woo Hoo!  That is one of my favorites! 
  • Also, the Plan of the Day (POD) for tomorrow states that the crew will be deploying and recovering the Fast Rescue Boat (FRB).  Sounds like fun!
  • I will share the results from the first Human-Interest Poll (HIP) of the crew.

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