Tag: ship communications

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Ginger Redlinger, July 17, 2007

NOAA Teacher at Sea
Ginger Redlinger
Onboard NOAA Ship Rainier
July 15 – August 1, 2007

Mission: Hydrographic Survey
Geographical Area: Baranof Island, Alaska
Date: July 17, 2007

Weather Data from the Bridge 
Temp: 56 degrees
Wave height: Negligible
Cloud: Cloudy and Fog
Visibility: ••• mile or less

Mariner word of the day: Strait A strait is a body of water – straight straits are straight bodies of water, but there are no wiggly straits. (Commanding Officer Noll provided today’s definition.)

Science and Technology Log

I got up early (0600 hours) to be sure to watch the crew navigate the ship from Peril Strait through Neva Strait, and then Olga Strait.  Can you imagine navigating a 231 foot ship though a channel that is a slightly wider than the ship and its wake, with only 14 feet of water below the keel?  Did you see the visibility distance in the conditions report?  Imagine how difficult it would be to see another ship approaching!  Well, these people are professionals. The deck hands steered the ship and watched from the decks with binoculars to catch any movement or objects on the surface of the water. The officers monitored two radar screens and checked the bearings constantly as they approached navigation markers.  They checked their route on the gyroscope compass to be sure they were not drifting. They constantly communicated with each other in their own terminology so everyone knew exactly who was doing what and where the ship was at all times.  Needless to say, the margin of error for passing through VERY narrow straits is small. The crew made a difficult navigation task looks easy.  This crew, deck hands, engineering, electronics, stewards, survey crew, and officers are exemplary.  I wish I could describe how well they work as a team – and I will try to help my students understand how important it is to work as a team –everyone has an important job to do.

The massive ship being loaded with supplies
The massive ship being loaded with supplies

When the fog cleared a bit I was able to see a variety of jellyfish in the water off the side of the ship.  A junior officer told me that when we drop anchor I will see more jelly fish than I can imagine.  I just hope my supply of camera batteries holds out! We will be entering deeper water in a few hours were I will be able to test my sea legs. (Which means that I will find out whether or not I will be seasick, or if will I be ok.) When we enter the sea beyond the bays, harbors, and straits that are protected from the seas constant motion, the boat will begin to move up and down and side to side with the waves and swells. After reading about the experiences of other Teachers at Sea, I decided to go the safe route and begin taking seasickness medicine ahead of time.  Does that make me Pollo Del Mar? (Chicken of the Sea – just a little chiste (joke) there!)

If you want to follow our journey on a map start at Juneau, go south to Gastineau Channel then head through Stephen’s Passage, north to Peril Strait, then west through Neva and Olga Strait. Pass Stika then head towards Biorka Island.  From this area we will head to our hydrography starting location and work as we travel.

A multibeam sonar transducer is installed on the bottom of the hull that will send signals to the ocean bottom and receives the data when it bounces back.  How does it work? Commanding Officer Noll describes it best, “The multibeam sonar precisely measures the time and angle of transmission/reception of the sound signal. The ConductivityTemperature-Depth (CTD) casts help us determine the speed of sound, which more or less allows us to apply Snell’s Law layer-based corrections to the ray-tracing of the sound vector that results. The data is converted to a picture of the bottom of the ocean.” Here is a picture of the transducer on the hull of the ship.  It is on the bottom of the ship’s hull, between the two posts that are holding the ship off the ground.

You may be asking, “why take speed of sound readings in the water before you survey?” Well, the speed of sound changes with the depth of the water so readings that pass through different layers have different velocities.  Accounting for those changes by correcting the data creates more accurate charts and maps. For more information about Snell’s Law and the refraction of sound waves, visit here. The ship runs a 24-hour hydrography work schedule.  The boat and crew will continue to collect and process data all day and night. This means that everyone will be working hard the entire time. If you would like to see a short animation clip of this work – click on this link.

Questions of the Day 

How much faster does sound travel in the water than in the air? Why is the velocity of sound faster in deeper waters than at the surface?  When you are mapping a deep part of the ocean, what impact would the changing velocity of sound have on the time it takes to travel from the transducer to the bottom, and back to the top again?

 

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Ginger Redlinger, July 16, 2007

NOAA Teacher at Sea
Ginger Redlinger
Onboard NOAA Ship Rainier
July 15 – August 1, 2007

Mission: Hydrographic Survey
Geographical Area: Baranof Island, Alaska
Date: July 16, 2007

Weather Data from the Bridge 
Visibility: 10 nautical miles (nm)
Wind Speed: calm
Sea Wave Height: none
Cloud cover: Partly Cloudy

Science and Technology Log 

Today’s mariner word:  Athwart (pronounced a-thwart) Athwart is a directional word that means “across.”  The ship’s “hallway” is the known as the athwartship passageway! Two other directional words are important to know too, “fore” indicates forward, and “aft” indicates the rear part of the ship. Today was a training day. It was fun learning all sorts of new words (or learning about new contexts for the some of the words I already know.  There is something really fun about getting out our your world (most of mine spent on land) and voyaging into some one else’s. Moving just beyond your “comfort zone” makes you appreciate that no matter how much you know there is always something worth learning.

Ships are well-run organizations. There is a chain of command for communication purposes that ensures that even in the most difficult situations, someone knows what should be done, in what order, where it needs to happen, and when.  This is a good arrangement in case of an emergency, but also to help the ship run smoothly as it prepares to travel or when it is underway.

An example of this happened today when I heard the announcement “All hands on deck for stores.” Which means, “okay everyone, the food and supplies for our next voyage are here and we need to bring them onboard.”  They are brought from the dock to the ship’s deck, from the ship’s deck to elevator, and from the elevator to the correct storerooms a few levels below the main deck.  We made a “fire line” and worked together passing the boxes from one person to another.  Everyone helped-out and in a short period of time, an entire truckload of supplies to feed and maintain 60 people for a 16-day voyage were stored. (Many hands make light work.  Many well-organized and hard-working hands make it VERY light work.)

I learned about the hand’s (people who work on the ship) schedules and assignments in order to learn when and where I can expect to see people, and what they will most likely be doing. I studied the ship’s diagrams and found the library on my own!  I don’t think I will need to leave breadcrumbs anymore to find my way around.  I leaned about Emergency Escape Breathing Devices; what they are, how they work, and how to use them. There are, in short, carbon dioxide scrubbers!  I also learned about the RAINIER’s procedures, by reading a binder labeled “Standing Orders,” which provided good background on how everyone on board is expected to work, what to do in case of an emergency, and what emergency communication sounds like.

The CO (Commanding Officer) spent time explaining how to get additional information for my logs.  The FOO (yes, sounds as it is spelled) Field Operations Officer was very helpful in providing me information about how work is planned, how to get additional graphics resources for my lessons, and what to learn about so I would have a great cruise.  He also asked me what I wanted to get from my experience.  XO (Executive Officer) made sure I had provided them with the information they needed for emergency contacts.  The Junior officers are also very professional, helpful and informative.  Chief Electronic – passwords and email account, and then there are two hands that helped train me on how and when to use my safety equipment and wear my survival suit.

We were underway by 1800 hours (6pm), and watching the crew get the ship underway was organized and efficient. Try to imagine what it would be like to coordinate, simultaneously, 60 crew members that each have a task, switching power supplies, testing systems, starting engines, testing the bow thruster, lowing a skiff for off-boat rope management, managing the ropes from the dock to the boat, raising the skiff back onto the ship while underway using a crane, while lowering the ropes and stowing them properly below deck. Meanwhile the officers are navigating busy ship channels (4 cruise ships in the bay, a gill net fishing boat, and ferries.).  Did I mention that dinner needed to be served to the entire crew during 1700 hours?  This team of people is amazing.

I could picture many of my students having a great time as a crewmember on this research vessel. I hope that I can bring back enough information to help my students see themselves as researchers, mariners, merchant marines, or join the NOAA Officers corp.

Question of the Day 

What is the distance in nautical miles (nm) between Juneau and the entrance to Peril Strait?  If we travel at 10 knots, how long will it take us to get there?