||From the Marina Office
Greetings Mariners - Here is your February 2018 Marina eNewsletter.
In this month's newsletter we have a collection of "sea stories" for you - some serious; some whimsical.
On the fun side we have the "Legend of the Scripps Canyon Sea Monster"; and the "Pollywog vs. Shellback" question. For the future, Australia's claim to the first rescue at sea using a drone tops the list. Lastly, on the serious side, some valuable information about boat accidents; capsizing; and potential fire hazards.
We hope you all are enjoying our fabulous Southern California winter boating weather, and we look forward to many more great boating days in 2018.
The Staff at Shelter Cove Marina
Shelter Island Boat Launch Re-opening
The Shelter Island Boat Launch Facility Improvement Project is currently 50 percent complete and is behind schedule, although efforts are being made to minimized delays in reopening. Here is a link to the full press release regarding the re-opening of the ramp.
Autopsy of a Capsize - Did "Wave Height" Have Anything to do With It?
- By Commodore Vincent Pica
When it comes to the forces that can cause a boat to capsize, tragedies abound that point to the urgent need for more understanding of the effect of wave height in this phenomenon by boat captains.
There is a tremendous amount of data on "Righting Moments", "Center of Buoyancy" and "Center of Gravity" thanks to the U.S. Navy and the U.S. Coast Guard, amongst many other institutions that literally live and die by these metrics.
To understand the forces of capsizing, and how those forces change when you load the boat, let's get some terms under our belt.
Most of us understand "Center of Gravity" (G) instinctively, but what is the "Center of Buoyancy" (B)? The Center of Buoyancy is the center of the volume of water which the hull displaces.
When a ship is stable, the Center of Buoyancy is vertically in-line with the center of gravity of the ship. So, as long as the Center of Gravity pushing the boat down is above the Center of Buoyancy pushing the boat up, we're good.
How good? That is a very good question and as with many good questions, it requires more information to answer properly. Take a look at this diagram.
What is that "M" sitting up there above our trusty Center of Gravity and the Center of Buoyancy? That is something very important called the Metacenter.
The Metacenter remains directly above the Center of Buoyancy regardless of the heeling of a boat (tilting caused by external factors like wind or waves) or listing (tilting caused by internal factors such as poorly stowed cargo or on-boarding of water by wind or waves).
Now take a look at this diagram. If you are starting to worry about the distance between "G" and "M" called the "Metacentric Height" (or "GM" in naval architecture parlance), you're catching on quickly.
The math gets pretty complicated from here but suffice it to say that the ability of the boat to right herself, i.e,, her "Righting Arm" or "Righting Moment" has a lot to do with GM. The larger the GM acting as a lever, the better.
Sail boats are designed to operate with a higher degree of heel (greater GM) than motor boats but the principles are exactly the same.
So, as we asked in the beginning, what does wave height have to do with capsizing?
You can infer that your motor boat's Center of Gravity and Center of Buoyancy can't be too far apart when the entire distance from the keel to the floor boards is probably something like 2' or 3'. Think of her draft. It isn't a big number, even for a 40 footer. No reason to panic but you now realize that M, G and B can't be that far apart, which means that GM just can't be that great either.
And GM is a surrogate for the righting ability of your boat.
But wait. I've been out in some pretty steep seas and I think the boat handled it well.
Yes, that's because studies conducted by the Society of Naval Architects and Marine Engineers (SNAME) determined that 3 things must exist for a capsizing to occur:
1. The boat is broadside to the wave.
2. The boat is struck by a breaking wave, and
3. Wave height must exceed a certain percentage of the boat's length.
When these three things occur, the wave contains enough energy to overcome a boat's righting moment.
So, what is that "certain percentage?" At only 30% of your boat's length, (about 6' from trough to crest for a 20' boat), things enter directly into the realm of high danger. At 60%, it is nearly certain that one wave will catch you and then you, the crew and the boat may well come to grief.
One Last Thought - Be mindful as you change the weight of your boat (with cargo or people), you change its Center of Gravity. This can make the boat 'more tender', i.e., it can reduce the Righting Arm, which makes the boat easier to capsize.
Commodore Pica is District Directorate Chief; Strategy & Innovation; First Coast Guard District, Southern Region USCGAux. He is also a U.S. Coast Guard licensed Master Captain.
BTW, if you are interested in being part of USCG Forces, email me at JoinUSCGAux@aol.com or go direct to the D1SR Human Resources department, who are in charge of new members matters, at DSO-HR and we will help you "get in this thing"!
Are You a Pollywog or a Shellback?
That depends whether you have crossed the equator on a boat or ship. (No, it doesn't count if you're at 30,000 feet or sipping a martini in the casino on a cruise ship)
"Crossing the line" is an initiation rite which commemorates a sailor's first crossing of the equator. Originally the tradition was created as a test for seasoned sailors to find out if their new shipmates were capable of handling long rough times at sea.
Sailors who have already crossed the equator are nicknamed (Trusty) Shellbacks, often referred to as Sons of Neptune; those who have not are nicknamed (Slimy) Pollywogs.
A rare status is the Golden (or Royal) shellback; a person who has crossed the intersection of the equator at the 180th meridian (international date line).
In the past, these initiation rites often lasted for a couple of days with brutal treatment of pollywogs including such things as shaving their heads, covering them with sea slime, tossing them into the hold, etc.
The usual final insult was a blindfolded visit to be hauled before King Neptune's Court on the aft deck and the requirement to "kiss the royal baby's ass". (Which after the blindfold was removed turned out to be the stomach of the portliest sailor aboard smeared with sea slime).
Australia Claims "First Ever" Rescue at Sea Via Drone
It might not be an exaggeration to say that drones are likely to change the world in the future on the same magnitude as the internet has done - and similarly, for both better and worse.
On the better side of the ledger, however, nothing shows more promise than the use of drones in search and rescue missions - both on land and on the water.
The internet is abuzz with companies anxious to get into the game of producing drones suitable for search and rescue operations and organizations anxious to start experimenting with them.
The U.S. Coast Guard has been looking at the prospect of getting a such a drone fleet for over two decades, but critics complain that to date, the Coast Guard has still not deployed a single drone.
Meanwhile, other countries and organizations around the world are pressing ahead, and two weeks ago on January 19th, in what is being described as "first", lifeguards successfully deployed a drone to rescue two boys in trouble while swimming off the eastern coast of Australia.
There was a lot of luck, though. Members of the Australian Lifeguard Service just happened to be training with the drone - which is being developed to spot sharks - when they got word that the swimmers were having difficulty nearby as they encountered a 9-foot swell in rough surf conditions.
The lifeguards steered the unmanned aerial vehicle (UAV), which is equipped with a flotation pod that can be dropped into the sea toward the swimmers who were 800 metres away. After spotting them, they dropped the pod with pinpoint accuracy.
The two grabbed onto it and made it to shore with the help of the waves. A team of lifeguards who had raced to the scene in an ATV greeted the two. They were unharmed.
The Legend of the Scripps Canyon Sea Monster
In the early 1960s, the Marine Physical Laboratory, which is a division of the Scripps Institution of Oceanography began experimenting with something called RUM (The Remote Underwater Manipulator) off the coast of the Scripps Canyon in La Jolla.
Launched from the beach next to the Scripps pier, the strange vehicle was designed was designed to crawl about on the sea floor at depths down to 6,000 meters to gather objects and samples, to take photographs, and to install deep-sea instruments
Starting with a Marine Corps self-propelled half-track rifle carrier; scientists added a boom and a steel claw that could be pivoted in any direction out to about five meters to pick up objects. The gasoline engine was replaced with a pair of heavy electric motors in an oil-filled compartment.
Sonar was installed, and a powerful light and four television cameras for sea-floor surveillance from a portable shore station (actually a bus). Power for RUM and sensor signals were provided by way of a coaxial cable 8,000 meters long.
Only problem was that nobody told the local population about RUM, so nighttime trials resulted in a frightening bright light moving about on the ocean floor. Police and news media were flooded with calls from people who imagined everything from sea creatures to foreign invasion.
Early tests of RUM were only moderately successful. On one of its earliest sea trials, in 1970, RUM placed two small sonar reflectors on the sea floor, crawled away from them, and returned to find and retrieve them. It also found a third sea-floor object:, a stewed tomato can that was found to be the dwelling of a small and very frightened octopus.
Rum was then set aside to be used in later projects.
What Are the Odds You Will Be Involved in a Boating Accident in 2018?
(Source: U.S. Coast Guard)
In 2016, the U.S. Coast Guard counted 4,463 accidents that involved 701 deaths, 2,903 injuries and approximately $49 million dollars of damage to property as a result of recreational boating accidents.
The fatality rate was 5.9 deaths per 100,000 registered recreational vessels. This rate represents a 11.3% increase from 2015's fatality rate of 5.3 deaths per 100,000 registered recreational vessels.
So compared to 2015, the number of accidents increased 7.3%, the number of deaths increased 12%, and the number of injuries increased 11.1%.
Where the cause of death was known, 80% of fatal boating accident victims drowned. Of those drowning victims with reported life jacket usage, 83% were not wearing a life jacket.
Eight out of every ten boaters who drowned were using vessels less than 21 feet in length.
Alcohol use was the leading known contributing factor in fatal boating accidents; where the primary cause was known, it was listed as the leading factor in 15% of deaths.
Where instruction was known, 77% of deaths occurred on boats where the operator did not receive boating safety instruction. Only 13% percent of deaths occurred on vessels where the operator had received a nationally-approved boating safety education certificate.
There were 171 accidents in which at least one person was struck by a propeller. Collectively, these accidents resulted in 24 deaths and 175 injuries.
Operator inattention, operator inexperience, improper lookout, excessive speed, and machinery failure rank as the top five primary contributing factors in accidents.
Where data was known, the most common vessel types involved in reported accidents were open motorboats (47%), personal watercraft (18%), and cabin motorboats (15%).
Where data was known, the vessel types with the highest percentage of deaths were open motorboats (47%), kayaks (13%), and canoes (9%).
One obvious conclusion? Having boating instruction; wearing life jackets; avoiding distractions; using moderate speed; and avoiding alcohol can reduce your odds of being involved in a boating accident dramatically.
A Close Call with Fire
- By Kells Christian
This sea story originates from an insurance claim we were involved with and comes with a lesson.
The story beings with the purchase of a five year old 45' motor vessel equipped with two diesel engines. The buyer had a marine survey and a mechanical survey at the time of purchase. She bought the vessel and hired a captain to train her in its operation.
Fifteen minutes into her fourth training session there was a change in the color of the engine exhaust smoke and subsequently they found the cabin thick with smoke.
A fire had started in the engine room. The fire was extinguished by a fixed, automatic fire extinguisher.
Our investigation found the fire was caused by a severely overheated engine exhaust system. The raw water pump impeller had failed, and was the root cause of the engine and exhaust system overheat event. The exhaust blew against combustible material and ignited the fire.
The captain stated that he had not been watching the engine instruments, but had heard no audible engine alarm. The recently completed mechanical survey did not mention a problem with the audible alarm system, but further investigation revealed the mechanic had found the problem, but that finding did not make it into the report.
The mechanic had provided his handwritten notes to the report writer, but the inoperative engine alarm note was written the report on the back of his field notes and the report writer missed this note.
This overheating scenario is not uncommon. It takes about fifteen minutes for a boat engine to severely overheat, in a normal usage situation. Had the audible alarm alerted the captain or the owner to the engine overheating condition, the engine would have been turned off prior to catastrophic failure and prior to the fire. Engines overheat all the time with very little consequential damage.
This story had a semi-happy ending. Nobody was hurt, we got a job, the insurance company paid a total loss and another boat was purchased. The boat broker sold two boats in a short period of time and was extremely happy. We assume the boat owner went on to pursue her dream of boating and lived happily ever after.
The lesson; audible engine alarms are critically important. Automatic fire extinguishing systems save lives. Boat fires are bad for you, bad for insurance companies but good for boat brokers and good for our business.
Kells Christian has been an accredited Marine Surveyor since 1990. His expertise extends to both recreational and commercial vessels. You can e-mail your marine surveyor questions to firstname.lastname@example.org or Click Here to visit his web site.