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Why Do Not Ships Have Headlights?

Every now and then we hear yet another story about a nighttime collision at sea, maybe between a ferry and a yacht or even between two large ships. Either way, the same question always comes up – why did not they see each other?

Sure, if it is nighttime, it is harder to see things, as you must have noticed it yourself when driving at night, you need headlights to stand a chance of seeing anything. Yet, when you look at a ship at night, they do not have headlights.

But why? If the headlights work fine for car, why not for ships? Well, think about what a headlight actually is. It is just a source of light, designed to emit photons which can bounce off objects and return to your eyes. Your brain then interprets them and tells you what you are seeing.

Simple enough but you need a light powerful enough to illuminate the area you are looking at. The power from the light is dispersed across the full width of its beam. Then, when the light hits an object, small bit of its beam that hits the object is reflected back, but it is again dispersed, meaning that only a tiny fraction of the original light gets back to you.

That is fine in a car, you want to narrow the area right ahead of you extending out far enough that you can take action to avoid the things that you see. Even at motorway speeds around 100 meters should be enough. You are probably starting to see where I am going with this.

With a ship 100 meters may not be enough to see your own bow, let alone to see far enough ahead to take any action. A large cargo ship, for example, needs more than a mile to stop. With two such vessels approaching each other, you are looking at needing at least two miles visibility to take action in time. You know how bright a car’s headlight is. Just think how much brighter a ship’s headlight would need to be to have the same effect!

Imagine two ships approaching each other at night. We have already established that they do not use headlights to see each other. So, what do they use? Well, they still use lights, but they are called navigation or nav lights instead. Every seaworthy vessel is fitted with nav lights the idea is that they are arranged in a standardized distinctive way so that other vessels can not only see you, but also identify how you are moving. As nav lights are fitted to the target vessel, their power only needs to be sufficient to be seen by other vessels.

If you have a light fitted as shown on the picture, rather than just relying on a tiny portion of reflected light, you can see howWhy Do Not Ships Have Headlights 2 much easier it will be to see compared to using a headlight.

But what about identifying their movement? Let us take this cargo ship as an example. She would show two masthead lights, the aft one being higher than the forward one. These immediately tell other ships in which direction she is moving. But she also shows sidelights. These are the colored lights that you probably know about – red for port and green for starboard. Again, it reinforces, which way she is traveling.

But the lights can tell us even more than that. If we are looking at the vessel’s port side and she turns towards us – as the masthead lights come in line, you can start to see both sidelights. You know the other vessel is heading straight for you. Take the look from above and you can see that the only angle where you would see all those lights is from right ahead. The observant among you will spot that these lights do not go all the way around either. Instead, we have a single white light filling in the sector of the stern, as shown on the picture. What this means is that if you spot a single white light, one of the things it could be is a power-driven vessel viewed from a stern.

If she turns a bit you can come on the cusp of viewing her sidelights and mast headlights, too. Looking from above, the only thing where this is possible, is along the white line shown – it is two points of 22.5 degrees above the beam – the very definition of overtaking we took straight from COLREGs.

Of course, we just looked at a power-driven vessel here but there are countless variations on this arrangement. You can Why Do Not Ships Have Headlights 3add extra mast headlights to indicate you are towing or show only side lights to indicate you are sailing. You can even modify your status by adding two all-round red lights to show you are not under command, or three all-round red lights to show you are aground or make the middle one white to show that you are restricted in your ability to maneuver.

See, nav lights tell you so much more that headlights ever could. They accomplish the basics making the vessel show up against the dark sky. But, in addition, they allow you to identify the vessel type, work out its aspect, and see which way she is moving – all vital information when it comes to applying the collision regulations, and working out which of you needs to give way to the other.

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The content of the first original title by Professor Toshio Hishima, namely "The Best Seamanship - A Guide to Deck Skills", was developed with his intention to help the deck crew members as well as the cadets to get to the better understanding of the different repair activities that they will get involved into onboard their vessels. Subsequently, the present publication was released, covering the shipboard machinery space activities.

The readers will start with the lathe work which is still quite basic and necessary-to-know information, followed by the gas and arc welding procedures and equipment. After that, they can proceed to the valves installed onboard their vessel, and here the coverage includes the technical maintenance of the valves, their types, replacement matters etc.

Working with slings is addressed within a separate chapter. The rest of the book ideals with the alignment issues, steel piping and its replacement, general works commonly carried out in the ship's engine room, and so many other important topics. The text is full of useful advices, that is the reason why the volume is so highly recommended.

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Nowadays, operating cruise vessels requires thorough knowledge of the cruise line work principles, which is a mixture of the different economic, technological, social, and environmental systems, forming the final product. The due attention shall be paid at all times to the uncertainties and conflicts that commonly arise when minimum of two of the above-mentioned systems are interacting.

This all creates serious issues for those dealing with the cruise shipping business. The idea of the authors of this book was to capture and duly document the most critical managerial challenges that the ocean cruise ship managers and operators have to face. Considering the number of people involved, this task is really of huge importance and needs to be addressed in detail.

The book is arranged in six parts, first one giving some general background of the cruise industry. The corporate, marketing and product management of the cruise lines are the topics of the following two parts, while the others will shed some light on the operation management, and future of the cruise industry.

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Another volume of those belonging to the world famous and popular Reed’s Marine Engineering series of books, and this one is going to provide engineers with all necessary technical information related to the heat and heat engines. The author of the book concentrated on the essential principles of the matter, and provided the text with the numerous illustrative and informative sketches.

It is a perfect tool for preparation to the examinations for the first- and second-class engineers. The content is full of the problems and examples, and each of them is provided with the detailed and explained solutions. There are as many as fifteen chapters in the book, starting from the common terminology and units, and the general info on the heat, thermal expansion and heat transfer.

Then, the students will read about the laws governing the behavior of the perfect gases, their compression/expansion, cycles etc. after that it is time to start with the internal combustion engines, boilers, reciprocating engines, turbines, and so forth.

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Here is an exhaustive collection of the “Review of Maritime Transport” publications issued by the UNCTAD, or the United Nations Conference on Trade and Development, since 1968. It will be of the great interest to all people involved in the international maritime shipping industry as, prepared by the recognized professionals of the world respected entity, it will allow reader to chase the developments that took place within the shipping throughout the past decades.

Needless to day that the content of each of the releases included in the pack, shall be highly recommended to everyone directly or indirectly engaged in the industry, and willing to be kept updated with all latest happenings and historical trends.

Made of the fifty-three volumes, this collection is the must have on the table or on the computer of any marine person. It also incudes a special volume released back in 2018 and providing the general coverage of the past fifty years, including the most important events. Get yourself a copy.

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Nowadays, talking of the maritime industry, we consider the innovation as one of the factors enabling the competitive advantage in the business of shipping. The increasing number of entities focus on doing their best to satisfy the demands of their consumers in terms of both qualitative and innovative products and provided services. This is mainly done through the application of the innovative methods to the supply chains, which, in turn, can be done by either technology- or non-technology-based methods.

The present volume contains a perfect collection of the works by the industry professionals, contributing to the above stated research fields, covering the methods and solutions, including the practices applied for the supply chain management. Among the topics addressed in this book there are the open service innovations as applied to the logistics, accelerating the innovation uptake, info flow analysis, computing dynamic routes, required security measures, problems associated with problems of the finite-time horizon logistics, critical success factors, control and monitoring, firm effectiveness and so many others.

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Use your chance to get the collection of the training videos from one of the most recognized sailing training providers. This is an excellent learning tool, especially for those making their first steps in sailing, as it provides the basic information in the different areas, making the coverage truly impressive.

The video lessons are arranged in eight sections, starting with the navigation aids, where the learners will get necessary information about the buoys and beacons, IALA buoyage system, light characteristics etc. Then they will proceed to the meteorology lessons including the weather information sources, Beaufort scale, interpretation of the weather fax etc.

The navigation is covered within the third section, including the navigation basics, plotting tools, compasses, nautical charts, dead reckoning and position fixing, passage plan, and shaping a course. Next is a lesson on anchoring, followed by the section addressing safety at sea, fire prevention and PF, standing for the personal flotation devices, MOB, or man overboard, distress signals, helicopter rescue, and liferafts. The COLREGs are dealt with in the separate section, while the remaining two cover the tides and currents, and GMDSS and electronics used onboard.

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The main intention of the author of the present title, Alfredo C. Robles, Jr. was to provide good coverage of the principal decision made during the Tribunal court held in South China Sea Arbitration in connection with operating of the law enforcement vessels in a manner that led to the potential collision with the ships belonging to the Philippine fleet back in 2012.

The detailed explanation of the provisions of the COLREG has been provided together with the incidents, involving the layperson’s terminology. The author has presented a detailed analysis of the violations which were done by the China vessels of the aforementioned collision prevention regulations based on the content of the previously classified documentation as well as the outcome of the technical works conducted by the experts in the field.

The research made by the author is really impressive as the sources of information used when preparing this report included numerous documents and reports in five languages, contributing in the holistic picture of what did happen and why. The volume will be interesting not only to the marine lawyers but actually to anybody willing to keep in the loop of the happenings in the industry and their underlying reasons.

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