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Maritime Technology

The CR4 source for all nautical topics—from boating and shipping, on salt or freshwater, for fun or commerce—all aspects of marine engineering and technology reside here. This also includes related topics such as marine products and electronics, offshore energy, marine conservation, navigation, naval defense and innovation, climate and weather, and perhaps even some relaxation and recreation.

Could Driverless Boats Boost the Shipping Industry?

Posted August 10, 2017 12:00 AM by Hannes

Some critics believe the world shipping industry is struggling. According to the International Maritime Organization, over 90% of the world’s trade takes place on the seas. But shipping companies overburdened with outdated container ships are scrapping them for a fraction of what they initially paid, major shipping lines are going bankrupt, and profitability in the industry is weak.

These conditions might make the industry ripe for innovation in the near future. Specifically, the shipping industry could take a page from automotive developments and turn to autonomous ships to alleviate the profitability issues.

Rolls-Royce is leading the charge toward remotely operated vessels, projecting that the first one could launch in coastal waters in 2020. About a year ago the company released a YouTube video imagining a futuristic “command center” remotely controlling scores of ships around the globe. While it’s tempting to dismiss this excessively overengineered vision, autonomous shipping comes with some potential benefits. Eliminating a crew of 16 or 17 workers for every ship makes the whole process safer. Seafaring is dangerous work: according to an Allianz report, between 1996 and 2005 UK vessels experienced around 11 deaths for every 100,000 seafarers. That’s 12 times higher than the general UK workforce. Other countries were even higher: Poland and Denmark experienced 84 and 90 deaths per 100,000, respectively.

The Allianz report claims that 96% of maritime accidents are the result of human error, and AI advocates (like Rolls-Royce) point to the fact that unmanned ships would obviously eliminate the operator fatigue problem. Autonomous ships could also reap other benefits, like greater efficiency and eventually lower costs. But the Allianz risk report mentioned warns that an overreliance on technology could make shipping more dangerous. The report cites several instances of accidents caused by faulty GPS equipment, including the famous instance when the Royal Majesty cruise ship ran aground near Boston in 1995. In the case of a malfunctioning autonomous ship, an onboard human could override the technology, but doesn’t this defeat the purpose?

Like autonomous vehicles, though, nothing is truly black and white, so the industry could employ AI technology piecemeal or only for certain ships. GPS-enabled autopilot has been common for some time, so a more mature version of this tech could bridge the gap to full autonomy. And even industry leaders like Rolls-Royce know that autonomous ships are even further in the future than autonomous vehicles. Until then, no need to worry what you’d do if a 500-ton supertanker—without a pilot, no less—goes rogue on the high seas.

14 comments; last comment on 08/20/2017
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The Sailboat Diaries: Building a Bilge

Posted July 20, 2017 2:07 PM by HUSH

For what it’s worth, I’m several projects ahead of my blog updates. I just haven’t had as much time to blog lately as I would like. Let’s hope that changes in the near future. (Also, kicking myself right now for not naming this blog series Ship’s Log!)

The bilge of my boat is to scale for a ‘pocket cruiser.’ It is considerably shallow (between 1-1.5 in. deep), and isn’t much larger than the sole of the cabin (roughly 8 ft. long by 4 ft. wide). It’s a small boat and like many smaller sailing dinghies it isn’t usually outfitted with a pump. It acts like a basin for the occasional topside leak, rain ingress or dripping-wet swimmer. Sailors with this type of bilge will typically empty it with a sponge or small siphon once back on land or at the dock.

Yet there are a few reasons why I need to install a bilge pump. First, there is a small hull leak around the keel trunk and on my shakedown cruise last October it was enough to fill the bilge in an hour’s time. (Apprently she was waterborne for most of 2016 with that leak.) Even though I intend to fix this leak completely, the ability to evacuate water from a 50-year-old boat cannot be undervalued. Also, to find and fix the leak, I’m going to need to fill up the inside of the boat with water; eventually all that water will have to be pumped out.

Lastly, my state is quite strict about invasive species and all bilges must by dry before a boat can be launched in a new lake. Several law enforcement agencies inspect and regulate this heavily!

Ideally my boat will have two bilge pumps for redundancy’s sake, but for now one will have to do. I elected a manual design because I didn’t want to have another appliance drawing electricity and also because most electric pumps are submersible, and none (or quite few) would fit the very shallow dimensions of my bilge area.

The Boat Owner’s Association of the United States recommends a pump output of 450-700 gallons per hour for a 20 ft. boat, and using this as my guidelines I bought the Whale Compac 50 (for myself, for Christmas, back in 2016).

Installation started by drilling a 3-3/8 in. hole into the storage locker underneath the port side quarter berth. I selected this location because it provided ample space to stroke the pump and also observe the bilge level from the cabin. The bilge gasket and deckplate installs on the outside of the locker and a removable handle ensures a clean aesthetic when the deckplate is closed. Installing the pump in the locker was painful because there are four screws the needed to be blind-threaded from the deckplate into the pump. After two hours and some blood loss I eventually got it aligned and tightened.

Bilge exhaust plumbing requires a mechanism known as a vented loop. This mechanism prevents water from siphoning back into the boat should the bilge exhaust ever find itself submerged. This is perhaps a little bit overengineered because my bilge exhaust is above the waterline and the manual pump should prevent water from siphoning all to way back into the bilge (which should only potentially happen on trailer launches and haul-outs). On my Matilda, the vented loop is positioned high along the inside transom wall, not far from the repair shown in Fiberglass-By-Numbers. It was screwed into a painted piece of wood that is epoxied to the fiberglass.

The 1 in. diameter pump intake hose runs underneath the boat’s kitchenette(-ette?). The sink currently drains right into the bilge so I ran the hose alongside that drain line, but continued the hose underneath the cabin sole. The end of the intake hose has a plastic screw-in strainer. The pump output, also 1 in., runs along the locker area before it has to extend underneath the cockpit floor so it can meet the vented loop. The loop is connected to a 90° stainless steel through-hull located on the upper starboard side of the transom. The hose connections are held tight by hose clamps, while the through-hull was secured with some 3M 5200 marine sealant and a plastic nut.

Today, I’m happy to report that my Matilda can expel water whenever she needs to.

Other completed tasks:

  • Installed six vents around the cabin and cockpit to increase airflow in storage lockers
  • Replaced all hardware on rudder assembly
  • Installed new tiller
  • Painted bilge cover boards

7 comments; last comment on 07/25/2017
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The Sailboat Diaries: Fiberglass-By-Numbers

Posted May 30, 2017 12:54 PM by HUSH

Summer is almost here which means sailing is kicking into high gear. Alas, my 1970 Matilda and I are still on the hard, at least for the next couple months while I finish her refitting. A cold winter made it unbearable to do much for her between late November to March.

For new readers and old readers alike, at the end of last boating season I bought a sailboat. She’s pushing 50 years old and although she’s structurally sound, there are many, many things, both mechanical and cosmetic, that I’d like to refurbish before she is rechristened and relaunched.

Autumn ended just a little early last year and I didn’t get around to my transom reinforcement. Instead that had to wait until early April. I elected to use System Three Epoxy Resin along with fiberglass roving to reinforce the area. Colloidal silica was added as resin filler to give a more peanut butter-like consistency, so it could be spread into the crack and not run as much on the inclined wall.

To begin I measured out and cut five sections of fiberglass roving and I labelled them 1-4 in order of application, which is also smallest to largest. Before applying the epoxy, I held these pieces dry against the repair area and numbered where I thought they should fit. Because it was a warm day and the epoxy sets in about 20 minutes, I needed to work efficiently and this ‘fiberglass-by-numbers’ technique seemed appropriate.

The first piece of roving was thoroughly wetted and wedged into the crack with the help of a putty knife. I did my best to prepare the area inside the crack by passing some sandpaper through it first. Subsequent glass cloth sections had their outline painted with epoxy and then were wetted on top with more epoxy.

Something I didn’t anticipate was the glass cloth roving conforming to the subtle rise in the transom wall where an original metal plate is fiberglassed in. In the middle of this process I cut a new third layer out of the cloth and made some cuts to the middle of the cloth the help with this. By this time the cloth layers were starting to tack and I had to put the fourth layer on immediately. (When the epoxy mixed up in the mixing container starts to smoke, you know you don’t have much time left!) The result is a final layer of fiberglass that doesn’t conform to the wall as well as the two layers before it (as the first layer is underneath the crack). Laminate reinforcement is messy work but is an essential skill for many DIY boat owners.

In the original transom reinforcement thread from last year, there was some discussion about adding an additional metal or wood bracket to this section. I was initially in favor of this idea, but had to abandon it for a few reasons. First, the largest bracket I could fit was 29 inches long, due to the working space of the lazarette and space availability of the transom wall. I also needed space to the left of this repair area to mount components for my bilge system (the next project). Lastly, I also bought the sailor DIY Bible, AKA Don Casey’s Complete Illustrated Sailboat Maintenance Manual. After reading the sections on epoxy laminates, I was comfortable moving forward without the brace.

From the beginning this was a peace of mind fix and not a critical repair. During the first few times that I fire up the outboard on the water I’ll watch this area for flexing and will also inspect throughout the season for evidence of increased cracking.

Ultimately this was just the first checkmark in a long list of projects, both ongoing and impending. Updates on my progress and questions for the community will be faster going forward.

3 comments; last comment on 05/31/2017
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The Sailboat Diaries: Ahoy!

Posted October 12, 2016 8:00 AM by HUSH

Welcome to the first blog post in what will be a long series of blog posts, entitled The Sailboat Diaries. The title is a bit romantic, but so is this project. And ‘Captain’s Log’ was just too cliché.

I had a few experiences sailing on square-rigged ships as a kid and teenager, and a handful more on beach catamarans. I’m also 100% a summer person—and I can’t think of a better way to spend a hot summer day than with family and friends on a boat in a New York lake or along the Connecticut coast. So after a year of late nights on Craigslist (looking only for boats, I swear), I finally found a small sailboat for sale at a nearby marina that suited me.

Anything in my price range was going to need a little work, and it was something I actually preferred. Not only could I make it my own, but I’d also have an excellent grasp on all the boat’s systems. And because this is being completed on a shoestring budget, I virtually cannot hire professionals. I’m not going to disregard safety in the name of time or money, but I at least need to try all repairs or refurbishment before going back to the marina.

So, with this prologue, I introduce my newest prize: a 1970, 20-foot, fractional-rigged sloop, model type Matilda, produced by Ouyang Boat Works in Whitby, Ontario. This type of boat is somewhat rare in the United States, but the designer, Robert Tucker, is a renowned boat designer with many other of his successful 16-25 foot designs taken into production. Since my boat isn’t officially named, she’ll be called Matilda until I’m finally ready to pick a name and apply the vinyl decal.

I wouldn’t buy a lemon of a boat—the previous owner had her in the water for the past two summers, but lacked the time to sail or maintain her properly. Matilda’s hull is in great shape, though it needs some gelcoat in spots and some bottom paint too. Fiberglass boats from this era are notoriously overengineered because people were skeptical if fiberglass (I prefer calling it glass-reinforced plastic) was going to hold up as good as wood. (I think today we know which won.)

Matilda came with 10 sails, nine of which are in great shape. A 6 HP two-cycle outboard is there for when the sails aren’t enough. A trailer that should last another decade or so.

But the boat is 46 years old, so she of course has her rough spots. I know for a fact I’m at least her fourth owner. She needs some transom reinforcement, which was turned into a forum post last week. I need to check for a leak around her centerboard trunk. The centerboard needs new steel cable, as well as a limiting mechanism to prevent it from overextending. I can’t believe there isn’t a single bilge pump in this boat! The electrical system looks like a mix of 1992 and 2012.

And then there are about three dozen cosmetic/comfortability projects. New boat cushions. New lights. Replacing the 1997 car radio with something even close to modern. How about a door or at least curtain to the head? Fixing the sink plumbing. Replacing the running rigging. An awning for the cockpit might be nice. We’ll definitely need a stove or grill on the stern. This list goes on…

I have no idea how long this blog series will go on. A year? Two? Maybe more? But I do hope you’ll take this journey will Matilda and I, even if you won’t be shoving off with us in 2017.

15 comments; last comment on 10/15/2016
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