Info Diving and Seamanship

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Akimbo

Just a diver
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I was with some old dive mates the other night and the newbie stories began to flow. On reflection, it reminded me that none of us are born knowing this stuff and very few get the opportunity to learn it. However, some of it is just as important to a boat diver's safety as sharing air or clearing a mask.

I thought it would be interesting to share information about seamanship. There are tons of different levels ranging from what to know for passenger safety to being a paid crewmember.

Need to know list:
  • Top of my list is learning to make an emergency radio call, especially if you are on a private boat or a small charter with only one crewman. People have died because the captain was out of commission and nobody knew how to turn the radio on.
  • Find out where the EPIRB is and why you need to know!
  • I would take a wetsuit or drysuit over a life preserver any day, but you should still know where they are.
  • Learn what life rafts or boats are onboard and what it takes to get them in the water.
  • Find out where the first aid kit and Oxygen are stored.
  • Verify what water onboard is safe to drink or potable.
  • Find out where Seacocks are and how to close them. (Thanks @Eric Sedletzky)
  • Find out where the Fuel Shutoffs are and how to close them. (Thanks @KevinG58)
  • Find out where the fire extinguishers are and how to use them.
  • Edit, 3 September 2019: Know all escape routes from compartments, especially berthing, in case of fire, collision, or grounding. See: Fire on dive boat Conception in CA
The following skills are very useful, but probably not essential. However, having them helps demonstrate that you are not a total neophyte.

Nomenclature: Nothing says "keep an eye on this guy" more than going to up to the "pointy end". The list can go on forever but here is a start:
  • Beam = the extreme width of a vessel
  • Berth = bed, but can also be where a large ship docks
  • Bilge = lowest inside part of the hull where water collects
  • Boat hook = pole with a small hook on the end to help snatch things in the water (gaff hooks are sharp and for snagging fish)
  • Bow and stern = front and back the vessel
  • Bow, stern, and spring lines = ropes that tie the vessel to the dock
  • Bulkhead = partition wall
  • Bunk = single bed, often stacked. Navy sailors often call them racks
  • Chine = the line along the sides formed by the intersection of the sides and bottom. Divers often swim along the chine to and from the anchor line
  • Davit = rotating fixed boom with a lifting system
  • Deck = floor
  • Galley = kitchen and food prep area
  • Gunnel or gunwale = railing around the outer edge of the deck
  • Head = bathroom
  • Hook = slang for anchor
  • Keel = fore-aft centerline structural member, round and flat bottom boats don't have true keels.
  • Knot (navigation) = A unit of speed, equaling one nautical mile (6,080.20 feet or 1,853.245 Meters) per hour
  • Ladder = stairs, unless maybe on a large cruise ship
  • Line = cordage of any size from twine to hawsers
  • Main Deck = typically the highest deck reaching bow to stern
  • Mains = slang for main engines
  • Overhead = ceiling
  • Passageway = corridor or hallway
  • Pilot house = where steering, navigation, and engine controls are located
  • Pitch = fore and aft rotation in swells (can also be a measurement of a propeller)
  • Port and starboard = left and right side of vessel when facing the bow
  • Prop = slang for propeller
  • Roll = side to side motion in swells
  • Rudder = flat plates for steering or maneuvering, usually aft of propellers
  • Screw = slang for propeller... but it might also be a fastener :wink:
  • Scope = the horizontal to vertical ratio of anchor line, but can also be slang for the radar display
  • Scupper = drain holes for water to exit from weather decks.
  • Salon = meeting room or lounge, often includes dinning
  • Stateroom = bedroom
  • Swim step = a platform aft of the transom near the waterline
  • Transom (in naval architecture) = a relatively flat part of the hull at the stern of the vessel
  • Wheel = slang for steering wheel
  • Windlass = the anchor winch (can apply to similar lifting aids)
Marlinspike Seamanship: Real seamen know how to tie a few important knots. Here are a few of my favorites:
This list barely scratches the surface but I am sure there will be a lot of additions… and maybe some entertaining stories. :wink:

Edit: Important safety items added to the "Need to know" list based on posts that follow, links included.
 
I still know my 3 knots from DM course--Two Half Hitches, Sheet Bend & Bowline. I practice them once a day--really. When I actually have to tie a knot, of course, it's still a Granny. I don't do charters so it matters knot.
 
  • Port and starboard = left and right side of vessel when facing the bow

good info, but I have one clarification based on personal experience:

Port and starboard = left and right side of vessel when on the vessel and facing the bow :)
 
good info, but I have one clarification based on personal experience:

Port and starboard = left and right side of vessel when on the vessel and facing the bow :)

Really? I thought for example the right side of a boat is always the starboard side whether you're on the boat or not, regardless of which way you face. If you're on land you say "We have to repair the right side of the boat"? If you're on board facing the stern what do you then call the right side of the boat?

I just Googled it. I believe facing the bow is only a way to describe which is port & starboard. As well, at night ships have one side lighted with one colour lights and the other with a different color.
 
Really? I thought for example the right side of a boat is always the starboard side whether you're on the boat or not, regardless of which way you face. If you're on land you say "We have to repair the right side of the boat"? If you're on board facing the stern what do you then call the right side of the boat?

I just Googled it. I believe facing the bow is only a way to describe which is port & starboard. As well, at night ships have one side lighted with one colour lights and the other with a different color.

I only meant to point out that if you are off the boat, and in front of it facing the bow, your left hand will be oriented to the starboard side, and your right hand will be oriented to the port side. Given the basic definitions in the OP, I thought it would be prudent to specify.
 
Nimoh and TMHeimer

A good demonstration of why port and starboard are used instead of left and right. An illustration is probably the best way to define it if someone can find one.

People don't have a port or starboard, but vessels do regardless of what direction we happen to view them from. The distinction can seem obtuse to people without much time afloat, but is critically important to prevent confusion. Just ask the captains of the Andrea Doria and Stockholm.

This might be a good time to explain colors associated with Port and Starboard. Port is Red and Starboard is Green. This is especially useful for navigation lights at night and buoys marking harbor entrances.

Navigation lights let you figure out the orientation of other vessels at night. Red buoys and lights are on the left side of the harbor entrance when leaving or heading out, and green is on the right. Of course that is the opposite when entering the harbor. The term "Red, Right, Returning" is a common phrase to help people remember.

There is a large set of instructions commonly called "Rules of the Road" that define all of this so everyone is on the same page.

Navigation Rules Online
 
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I've only got 15 years experience running a small (25 foot) boat here in Belize. One important thing I work in is reading the weather. And if it turns to **** really fast, what to do….I've had three incidents where I was giving thanks as I stepped onto dry land. Once with my 2 year old son in my arms after a squall that wasn't predicted at all.
Surfing experience and wave knowledge has helped me in really choppy weather.

It's an ongoing lesson. You never know what Mother Ocean might dish out…..
 
https://www.shearwater.com/products/perdix-ai/

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