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XPM-002 Vanguard will operate with a short-handed crew. Minimum one and average two crew. Safely docking and maneuvering a 78-foot motor yacht under such conditions presents considerable challenges irrespective of experience level. We also have a need to maintain the vessel on station in environmentally sensitive areas with restricted anchoring and when at anchor to keep bow on to the swell (if we can't manage this with a spring line on the anchor chain). Docking Assistance: The Target Save my marriage when docking - aka " no shouting at my Missus " Save my insurance premiums - aka " no bangs, scrapes or salvage " Save my arms, legs and fingers - aka " peace and tranquility rein " Our machinery and control systems specification targeted assisting the operation with an absolute minimum crew. Early in the design process we looked at systems such as Dockmate, Assisted Docking from Volvo Penta or Dockcommand from Cummins. Great systems in themselves but not developed to optimize the drive configuration we had installed. They are typically for planing boats with bow and stern thrusters or azimuthing Pod/Z Drives. Docking Assistance: Dynamic Positioning Theory Docking Assistance Dynamic Positioning systems account for external forces acting upon the vessel, such as wind, waves and current. One common feature of a Dynamic Positioning system is a station-keeping function. This is the vessel’s capability to react to external loading to maintain a certain position and heading [1]. This capability is affected by the equipment configuration the number of propellers, thrusters and linked or independent rudders. In the example below, Vanguard has the same configuration as example C3 [2]. Bow thruster, twin propellers and independently operated rudders. The Dynamic Positioning system capability is represented as a polar diagram or DP Capability plot [2]. This is a plot of the ability of the vessel to maintain station as the opposing forces are swing 360 Deg around the hull. It plots the limiting value at all angles. In the example given it is evident that the limiting condition is on the beam where external forces have the greatest effect on station keeping. The Hull Machinery XPM78-002 uses a diesel-electric hybrid drive providing high and controllable thrust from two propellers with rapid reversing. Electric drive provides these propellers with high torque at low shaft speed. Additionally, the vessel carries a 12kW 250mm Sidepower bow thruster with proportional control. Two independent and oversize rudders provide a rapid 80-degree swing. Motors, thruster and rudders are linked to the DP Control system. Docking Assistance for a Large Explorer Yacht: The Solution A Mega-Guard Heading Control System from Praxis Automation controls the setup. This is a traditional heading control system (autopilot) linked with software from a Dynamic Positioning system also provided by Praxis [DP0]. Such systems [DP1, 2 or 3] are used in the oil exploration industry, the difference being a reduced redundancy allowance and isolation requirements as our Yacht is less than 24m LOA. The DP software allows control thrusters and engines as well independent rudder control. The system is connected via NMEA 0183 interface to Heading, Wind, and GyroCompass sensors. It communicated with thruster, motor and rudder controllers via dual redundant Ethernet backbone. Operation is by touch panel and joystick control located at the helm, flybridge, and aft docking stations. The vessel will keep a consistent heading OR remain on station OR held hard against the dock in winds speeds below approximately 20kn and tidal streams of 3kn(on the beam). By installing an advanced hybrid electric drive, bow thruster, and twin independent rudders, all linked via the Praxis Mega-Guard Heading Control system, the XPM78-002 can be maneuvered and docked in safety by a single crew member. Or at least that is what the modeling tells us and the systems are already used extensively in commercial applications. Naval Yachts believe this is a first in extending the capabilities of much larger commercial vessels to a yacht of this size and considerable capability. Dinner Dinc - Naval Yachts Chris Leigh-Jones References [1] - Dynamic Positioning Capability of Superyachts, BMT Technology [2] - Dynamic Positioning Assessment for the Design and Comfort of Large Yachts, Maritime Research Institute of Netherlands, Strathclyde and Trieste Universities.

Read also: Visiting Praxis Automation - Part 1 A Scottish poet once opined, " The best-laid schemes o' mice an' men / Gang aft a-gley ." or for us lesser mortals, " despite careful planning, something may still go wrong. " We started this project with good intentions but an unsolidified plan. Now the end is in sight, and it is time to review and adjust in light of the experience gained. Or, in the words of a different bard, " ain't education a bitch ". Praxis are top of their game for supply of monitoring, control, power management and hybrid propulsion systems to commercial marine applications and a substantial number of Navies. Our visit to Praxis was an opportunity to review and refine their equipment as it applies to our own explorer yacht project. The project has experienced scope creep since first proposed. Four examples are: The addition of two CAN-Bus gateways to convert J1939 engine signals to Ethernet that the control systems require. An additional controller so we can operate rudders independently in support of more practical dynamic positioning. An independent fire alarm system split it into discrete loops and identifies individual alarm heads. Integration of a Mil Spec FLIR with IR illumination laser for spotting ice and objects in our path. A range of screens that will be located at helm and engine room were connected to test functionality. Note engine & joystick controls are reinforced composite for operation in low air temperatures. Now is when software is compiled to bind all the disparate components into one cohesive, logical system. Vanguard is built to be simple (we hope); with that in mind, we have limited control functions relying primarily on reporting as and when necessary. Reporting is via dedicated MIMIC displays covering the various systems and alarms. Product development does not happen in a vacuum but builds on the past. Our task was to distill that into a system understandable by a small crew under some pressure. So where we could combine screens we did, Navigation lights, weathertight access, and bilge alarms were combined on the same screen. Tanks, range, remaining liquid levels, and usage rates were combined similarly. Information can be transmitted textually but also graphically or by position and color. A complex screen may contain information needed but try reading it when you are cold, tired, and just broke your glasses. So we tried using precise color, shape, and position to simplify the layout for a quicker understanding. The acid test is my wife, Sebrina; unlike my nerdy self, she has no fundamental preconceptions, if Sebrina gets it, we are good to go. Time will tell. Example MFD display setup at Praxis offices, I quite liked the way the screens were mounted. We also spent time understanding the equipment beyond reading the brochures. For example, I (& the UK Marine Coastguard Agency) are nervous about the uncontrolled thermal runaway of LiPO battery packs. 120 kW.h is a lot of energy to contain. Examining the design revealed that each battery rack consists of 16 isolated cells ( blue in photo, exhaust is the light blue bursting disc ). Each cell is cooled and monitored, having a dedicated exhaust ( aluminium Chanel on green PCB ) and thermal isolation in the event of a runaway. Each of the 12 battery racks is also independently contained and exhausted outside the engine room environment. So one single failure will not cause a runaway of the entire bank. The outer casing creates a practical battery room independent of the leading machinery space, thus satisfying Classification requirements. We took time to examine the E-motors; there is nothing like a practical trial to stress test marketing speak. Our two E-motors were connected to a battery pack as a single motor and generator setup. They were run under full load, and the battery charge depletion was monitored. This tested the combined efficiencies of the battery cycle, two inverters, two line filters, and the motors. Something like 90-95% overall. We were pleased with that, so it's a pass. Photo shows battery management operating at 598VDC, 2Amps (10kW) at 28% charged (LiPO can discharge more deeply than Lead acid ). The scope of supply and equipment location was next. Our initial scope for signal Input/Output (I/O) could be reducing the number of modules needed as we focused on reporting rather than control. Other logic controllers (PLC) and I/O modules could be sensibly combined, reducing the engine room cabinet count. Dynamic positioning configuration was also amended to a single machine with simple repeaters at valid locations rather than everything in triplicate. Finally, we asked for the drawings to be updated to reflect the "as supplied" system scope. Even with a push for simplicity, motor yachts are complex machines that change in gestation. Lucky is the final crew with drawings that reflect the reality in front of their eyes. All equipment will now be crated and shipped to Turkey before Christmas. The software will continue to be developed for the next month before being available for download. Our long-running game of Whack-a-Mole appears to be drawing close. Time Zero navigation software downloaded to 4 by 24"MFD screens, chart software to be added . Chris Leigh-Jones Thanks to Praxis Automation for their hospitality and consideration. Especially to Nico Ouwehend and Tobias Anderson for patiently tolerating my constant questioning. Praxis is not a low-cost supplier. Our decision was based on their reputation, comprehensive supply scope, and global marine support network. "Pass the blame" can be a frustrating game when far from home. There is real value in the monitoring, control, navigation, helm, data network, and hybrid drive system supported by a single phone number.

Our monitoring and control system partner is Praxis Automation from Leiden in the Netherlands. Dutch people seem born with two charms attached, bicycles and boats, so when it comes to yacht equipment, they are top of their game in most ways. It was a two-day visit to inspect a simulation of the final scope of delivery and the software package in its preliminary form. After an initial introduction, we got down to business, starting with the drive line. Explorer Yacht Monitoring & Control System Our explorer yacht has a duplicated driveline similar to the illustration above; we will look at a single side for now. We have a John Deere 4045 diesel feeding through a clutch into a mechanical step-down drive PHT from Esco Power. This drive connects the hybrid motor to the driveline allowing it to run at higher than engine speed. The drive line then passes to a Twin Disc gearbox before going through a self-aligning coupling and onto the propeller shaft. So far, so good. Operating modes are as follows: 100% diesel driving the propeller, engaged clutch, gearbox engaged or disengaged 100% electric - diesel clutch disengaged, gearbox engaged diesel and electric - basically everything running. Finally, in generating mode charging batteries from the diesel with or without the propeller connected and spinning. Table 1 shows the various ratio involved, along with some governing performance parameters. Our next task was to run through the various operating modes and consider how they perform with time when loaded, unloaded, or poorly treated. There is no right or wrong here, but it is worth a look. Firstly we checked the various speed limitations. E-motor 1500-3600 RPM max 30kW power - 90kW generation Engine 1000 - 2300 RPM max 120kW max, clutch to PHT, fixed to E-motor and gearbox. PHT fixed 1.46 (not as thought 1.7) 250kW max Gearbox 2.5 to 1 step down 250kW max, F/N/R Problem - early documentation for the PHT drive indicated a gear ratio of 1.7:1 or 1.46:1 2300x1.7=3910 >3600 RPM limit on the E-motor, so we have an immediate problem! Solution - revert to the supplier (Navantec) to verify the "as built" PHT ratio. It is now confirmed at 1.46 - good to go after a brief heart-stopping moment. Problem - Engine operating at max revs of 2300 RPM, electric motor spinning, unloaded at 2300x1.46=3360RPM Solution - it checked out, and we are good to go. Problem - Engine 15% over speed. Engine operating at 2300 RPM, E-motor load removed by de-energizing stator causing over speed. 2300*1.15*1.46=3861 RPM >limit of 3600RPM. Additionally, max high unloaded idle speed can creep up from 2300 to 2350 or 2400 RPM as the Engine Management System only loosely restricts it. Solution - software limits the maximum engine speed to 2300 RPM. E-motor over speed is mainly an issue of fatigue, so a short duration of over speed acceptable if otherwise uncontrolled. Problem - Shock load on the drive line. Engine operating at 2300 RPM, E-motor instantly energized, causing shock load on drive line from near-instant 30kW additional load. Solution - software limit rate of rise of stator excitation over 10-second ramp > response time of engine governor allowing sufficient engine reaction time. Problem - Overload, engine running at full load driving the propeller, then the E-motor switched to generator mode with the effect of a steeply altered propeller load curve. Solution - The Energy Management System will parse the load from the drive line to the E-motor in a controlled manner via engine set speed reduction. (With a fixed pitch propeller, the engine set speed controls the maximum load.) Problem - Accidental propeller rotation. Gearbox in neutral but drag on driveline or propeller in a current. Solution - oil pressure activated brake on the propeller shaft. As E-motor is permanently rotating with the shaft, add a 3-phase electrical breaker between the stator and Hight Power Inverter for safe future maintenance. Problem : John Deere Engine controls allow short-term overload to 110%max. Engine software limited to 2300 RPM by Praxis Energy Management System. Solution - provide manual override, time-limited at 2400RPM for 5 minutes. The owner (us!) will take responsibility for fatigue failure. Read also: Visiting Praxis Automation - Part 2 Engine controls and one screen of the Energy Management System that interfaces engine, PHT,Gearbox functions. It is unusual to find both the owner and supplier of marine equipment in the same room simultaneously and without the usual chain of command up and back through the Yard and the Owners Representative. This short line of communication allowed us to step through each identified problem scenario, discuss the implications and draft an action list of preferred solutions during a two-day visit. Apart from 24 aged-body-deforming-hours on a plane, I'd suggest this is a good use of everyone's time late in the project. Chris Leigh-Jones My thanks go to Praxis Autionation, especially their excellent staff and our project manager Tobias Andersson. Also, a shout out to our supplier of hybrid PHT drive and steering systems, Okan of Navantec, who managed to send a considered and informative reply within a few hours of our request. Remember - hybrid drives allow for easy maneuvering and almost full energy independence, they are nota. solution for long voyages on electric only.

We had to specify our explorer yacht electrical system. Oh dear, I was quite stumped. But I did know a man who could help, enter Rob Westermann, CEO of Artnautica Europe, and, over the months that followed, a friend of mine. Vessel Electrical System Design: Abstract How to design a hotel or residential electrical system for an ocean-going LRC/XPM vessel? This document covers the steps a qualified Electric Schematic marine electrician (from now on, “ES designer”) takes for an ocean-going LRC/XPM vessel that can be used to implement an electric system. We assumed Chris had no prior knowledge when designing an ES for such a vessel. He is probably in good company! Solar MPPT controllers, 24VDC bus bar, and distribution rail for Vanguard 24VDC system. CE / Code of Practice - the Boundaries to Work Within Firstly determine the applicable Code of Practice. This will form the baseline for the ES designer. For instance, in Europe, leisure vessels must adhere to the CE standard/certification, or the owner may opt to comply with the Netherlands' Human Environment and Transport Inspectorate (ILT) Code of Practice. The Maritime & Coastguard Agency (MCA) Code is often chosen in the UK and in the US, the American Boat & Yacht Council (ABYC) Code. A European owner may opt to have the vessel comply with the MCA or ABYC Code besides the CE certification. The chosen Code of Practice will ensure that the resulting ES drawings meet the chosen Code of Practice requirements. The Certifying Authority will test the resulting ES as one of the steps required to grant the vessel a CE/MCA/ABYC certificate. List all Consumers and Add Power Requirements for the yacht electrical system Begin by listing the consumers (12/24/48VDC and 120/220/400VAC), preferably with their position in the vessel. There are several ways to perform this task. One is to put together a list for each DC and AC consumer and add their power requirements and the amount of time they will be on every 24 hours. Three versions are needed when sailing, at anchor, oh, and using shore power. Example energy balance for an LRC58 considering "at sea" and "at anchor" conditions. Note the positive contribution of Solar when in full sunlight. Another way is to list all vessel compartments, plan each compartment's planned consumers, and determine what voltage they need. The latter is the preferred approach because it enables the ES designer to lay out and determine the length and, by definition, the size of the DC/AC cabling in the vessel. Note that if the vessel is equipped with diesel-electric (hybrid) or electric propulsion, the ES will require an additional format to cater to this setup. It will also provide the opportunity to arrange the system around a much larger battery bank. This raises the possibility of considerable time at anchor with no generator running and near total silence. However, charging such a high storage capacity by generator or shore power becomes a more intractable issue. Shore Power and Solar / Generator Power Shore power requirements will depend upon the cruising grounds, this can be quite a workup, but for this article, we will look at 120 and 240VAC requirements. We will need both an isolation transformer (mandatory for aluminum vessels) and to allow for 50/60Hz input. It is often a simple solution to convert everything to DC and accept some transmission losses to remain independent of frequency and independent of potentially serious electrical accidents when connecting. For worldwide ocean-going vessels, ideally, the system must cater for 120/240VAC, 50/60Hz single phase, and depending on the vessel's power requirements, 400VAC 50/60Hz 3 phase must be added. Look at this Blog for further reading, including 3 phase power considerations. Next, decide how much solar power the vessel can accommodate. And decide whether a generator (or two) is needed (hybrid yachts offer the prospect of removing the generator completely). Solar power schematic for an XPM78, approximately 6 kW peak capacity providing near 24-hour energy independence. Yacht Electrical System-Specific Data The last step is to collect the system manuals and datasheets that outline system installation and operational specifics. For each consumer, this will make available the voltage (12/24/48VDC, 120/240/440VAC) and the consumer's power requirements. It will also make available information about which breaker/fuse to use to protect the individual consumers/systems in case of malfunction. Select a Qualified ES Designer With all the information in hand, find an experienced ES marine electrician with a proven track record for similar vessels. Sometimes, the yard where the vessel will be built has a working relationship with one or more qualified ES designers. ES Design Process (Block Diagram) Supply the ES designer with all the information collected thus far. They will then draw up a high-level overview or Block Diagram (BD). This BD will identify all significant elements of the ES, such as shore power details, isolation transformer, and inverter(s). It will also show the various battery stacks of the vessel's power system. Moreover, it will show the number and positions of DC/AC cabinets needed to distribute and control the power. Block diagram for Vanguard. this includes the 120/240VAC* single-phase shore power connection but not the 3-phase option. Note three "Victron Multiplus," used to convert 3-phase to DC, will also operate in reverse converting single phase or residual 24VDC power to charge the power batteries as a last resort. Also, some tiger power AC loads are retained at 3-phase (bow thruster, galley oven & cooktop) to better balance the three 240VAC phases. Lastly, the BD highlights significant components such as engine(s), generator(s), thrusters, and winches and their global position in the vessel. Judge the first version, adapt and detail further, and keep doing this until both the owner/yard and the ES designer agree upon the BD. Note: Total potential load is 165 amps, but not all equipment operates simultaneously. Thus the likely load is (-)20 amps. Why is it less than zero? Look at the large solar panel installation; when operating in full sun, it will power all systems and charge batteries with little remaining. The ES will be augmented with a "load balance" (LB) sheet. This determines how the various components, such as isolation transformers, inverters, and battery stacks, must be quantified in electric power. Lastly, the BD must be presented for review by the Certifying Authority. After approval, the ES designer can move on to the next phase. Yacht Electrical System Production With the approved BD in hand, assign the ES designer to extend and detail the BD. This again will be a step-by-step process, and during this phase, each version will be shown to the owner/yard and can be commented on. So supply him/her with questions/suggestions/remarks found each time. Judge the version the ES designer will produce, give feedback to the ES designer, and keep doing this until all parties are content. Yacht Electrical System End Result The result will be a fully-fledged description of the ES that a marine installation company can use to perform the actual installation of the ES. The ES will contain all systems, cabinets, and cabling requirements governed by the length and size of the cables in the vessel, detailed lighting, and system position plans. Again, this version will also be approved by the Certifying Authority before installing the ES. Extension of the block diagram showing shore power isolation transformers and DC chargers with a focus on cable specifications. These components will later be made controllable via a Victron Cerbo device. * for practical purposes 110 & 120VAC are interchangeable. The same applies to 220/230/240VAC. Final Recommendations Update yacht ES while installing While installing the ES, changes will be made to the schematic, such as cable routing with a possible change in cable thickness, system additions/changes, and the like. Make sure that all the changes are immediately reflected in the electrical drawings. Keep updating vessel ES while sailing Since things will change during the vessel's lifetime (most notably, systems will be added/cable runs will change/breaker functions will change), it is good practice to update the ES at regular intervals. When selecting the ES designer, make sure that they have the potential to do so ongoing. Lastly, take it all one step at a time; it's not that difficult, and ... good luck! Rob Westermann - Artnautica E urope About MCA "It is a legal requirement that UK vessels (up to 24 meters load line length) in commercial operation or charter use, carry no more than 12 passengers and cargo, comply with the Maritime and Coastguard Agency (MCA) Small Commercial Vessel and Pilot Boat Code of Practice and be issued with valid Certificates by a recognized Certifying Authority." About ABYC “The ABYC is a non-profit, member organization that develops voluntary global safety standards for the design, construction, maintenance, and repair of recreational boats.” About CE “All new and used boats (up to 24 meters in length) being sold in Europe must be certified as conforming to one of four CE (European Conformity) categories: A, B, C, and D. CE-A rating covers largely self-sufficient boats designed for extended voyages with winds of over Bf 8 (over 40 knots), and significant wave heights above 13 feet, but excluding abnormal conditions such as hurricanes."

The time has come for us to review fuel and water tank capacities on Vanguard. We were spurred by adding a unique need for Water/Glycol cooling systems required by the hybrid drive. So to kick this off, we looked at a few similar hulls to get a better feel for what the market is looking for: 1 – first off, we looked at other high L/B ratio hulls, specifically FPB78 and XPM78-01. These were both the same length but differed in their beam and internal layout, 3 and 2 cabin designs. (Design details for the Circa Marine 24M are not easy to find). 2 – then, we looked at another displacement hulls with three cabins and similar internal volume – Nordhavn 64 , single-engine, and Bering 65 twin-engine.  Explorer Yacht Tank Volumes 3 – we looked at semi-planing hulls of similar layout and internal volume. Twin-engine Fleming 65 and Ocean Reef . Table 1 below displays the results for fuel and water tank storage capacities across different yacht brands. What is immediately apparent is the installed power with FPB78 and XPM78 series being significantly lower for a similar speed profile to the two other displacement hulls of Nordhavn and Bering. Even more so for the semi-planing hulls. Conversely, FPB78 and XPM78 have significantly higher freshwater tank capacities. This capacity is partly as a ballast function (see fuel tank capacities) and party to reflect their passage-making profile where convenient marina facilities are far and long apart.  Grey and Black Water Grey and blackwater tank capacities were a little harder to find. Greywater is easier to deal with and, in most cases, can be discharged overboard unless in environmentally sensitive areas and some freshwater lakes. Discharge may become more restrictive as the legislation progresses, so we decided to install these tanks for all shower and sink drains. We will probably lead HVAC drains overboard. Blackwater is subject to pump-out requirements at marina facilities or defined distance offshore, typically 3 miles. We split our tank capacity 50% Grey, 50% black. Greywater can overflow to black if necessary but not the other way around. Greywater tanks will be marine-grade aluminum hull tanks; black water will be polypropylene fabricated tanks to limit corrosion. Eight hundred liters capacity for each seems in line with the other 3-cabin yachts irrespective of hull design. We will create an interlock in the Helm Station mimic diagrams to prevent unwanted discharge in restricted waters and install remotely operated valves in the system.  Yacht Fuel Tanks We looked at the fuel tanks. In considering these it is also necessary to consider installed power on each vessel. We estimated operational engine power as 60% of installed capacity except for the high L/B hulls where the second engine provides redundancy and is not power. At 60% power, we assume that the higher-powered hulls are not yet planing.  Tanks on Vanguard are smaller than XPM78-01 with similar hydrodynamic power needs and FPB78 with a slightly wider hull. However, the range remains about 7000 NM with 20% reserve , and we do not feel the need to increase this. The one change we would like to see is a reduction in the volume of the day tanks. Three-day capacity is ample, and we would like to remove a little weight from the stern of the hull and add a little more space in the engine room.   Yacht Water Tanks Then we looked at water storage tanks. Some of this capacity is designed as ballast compensation to keep trim as the fuel reduces. Vanguard will have an onboard water maker additional to any shore supply. We decided to retain the large water storage capacity, it adds redundancy should the water maker fail and we will need the ballast capacity to counterbalance the fuel tanks as they deplete. Hybrid Drive Yacht Cooling System Like many EV’s, our cooling will use ethylene glycol in a 50/50 mixture. That gives excellent heat transfer performance, low freeing temperatures, and corrosion protection for any metal it touches. Due to its toxicity, the imperative is to keep it isolated from any potable water tanks and systems that minimize accidental contamination risks. Water/Glycol system could cool the batteries, inverters, EV Motors, hybrid drive gearbox, and main gearbox. Engines themselves have antifreeze coolant systems that we will leave as supplied.  XPM78-02 – Vanguard Tank Storage Plan Space exists in the engine room bilge between and aft of the engines. Three frames will allow for a cofferdam aft of the freshwater tanks. Seawater in contact with the bottom skin area of the tank will cool the contents and (less efficiently) internal air contact. Being set low in the hull, any systems not operating will drain to the sump tank removing toxic ethylene glycol from the lines when possible.  By eliminating seawater, we eliminate corrosion and fouling. We can also consider fitting third-party sealed plate coolers instead of traditional tube coolers with corresponding weight and size reductions. The engine cooling system can remain independent as there is a wet exhaust system installed so we cannot eliminate the seawater flow.   I’d be a little nervous about this idea if the systems were either high-powered or continuously running. Apart from the engines, the operation is periodic, in the order of 1 or 2 hours. For all systems, the cooling requirements are pretty modest, in the order of a few kW. We still need to undertake a heat balance for the system to double-check, but I think we are good (see later Blog). The fallback is to add a parasitic seawater cooler into the system, which we would rather avoid right now.  Conclusion for Fuel and Water Tank Capacities So the final design has: retained most fuel and water tank capacities and their effect on trim and stability.   class-leading fuel range at >7000miles @ 10kn more potable water/ballast than you need to fill a small swimming pool ample greywater, and blackwater capacity.   a nifty, passive water/glycol cooling system suitable for high latitude operation, removing most seawater systems from the engine room.  Items 1 through 4 came at no effort thanks to work already undertaken for hull number 1 Mobius. Item 5 is our add-on to that configuration.  Read also: Aluminium, Fibreglass, Steel or Wooden Hulls? Read also: Explorer Yacht, Electrical System Design

The following letter was written by Wayne, owner of Mobius in answer to a question of fitting either a Controllable Pitch Propeller or a self pitching Autoprop type design to an LRC58. Mobius is single engine & rudder design fitted with a 160 BHP Gardener engine. In either case, the condition to avoid is high BMEP (Brake Mean Effective Pressure) and reduced engine revs. This is the operating envelope where the incidence of bore polishing increases. A typical example would be beam trawlers when nets are deployed greatly increasing the hull drag and lowering the speed. Anyhow, over to Wayne …… “Re your questions on AutoProp, short answer is that I am a big fan of them and seriously considered one for Möbius. I had them do a similar set of graphs for us and they were appealing. Yacht Propeller Test I considered choosing the AutoProp for Möbius but in the end as you know, we decide rightly or wrongly (we’ll see) to go with the Nogva CPP. While I think the AutoProp would have worked well and is arguably more simple way of getting some variable pitch in a very “automatic” way, it is our belief that the CPP will give us even better performance in terms of being able to optimize the Gardner’s power and torque. The big deal for me with CPP is the ability to dial in the pitch for ANY set of conditions we encounter. No matter what speed we want to be cruising at we can adjust the pitch to put the loads on the engine to be in the “sweet spot” of the fuel map where we have the just right amount of load, EGT (exhaust gas temp), RPMs, etc. This is ideal for both maximum lifespan on the engine with the right loads and RPM as well as the best possible fuel burn rates for that situation. Surprisingly, when you go through a full cost analysis, a CPP is pretty much the same cost as a fixed prop or an AutoProp assuming you are comparing like to like quality of components wise. The unit we got from Nogva was exceptionally complete including not only the 4 blade CPP prop and servo/gearbox, but also the AL prop log tube which made it very easy to weld in the surrounding prop shaft tube into the hull during the initial hotworks of the build and then used Chock Fast to set the Nogva tube into that. Also included the Tides Marine “no drip” shaft seal system which works very well in my experience. So when I took into account the full list of items you need for both a fixed prop system and the AutoProp system, and kept all those components top quality materials and companies, the cost was close to the same for both.NOT trying to sell you or the LRC58 client on CPP, just giving you some of the background on our decision. Back to the AutoProp, it worked very well for us on Learnativity. It is basically a “install it and forget it” kind of unit and all I ever did was grease and service it every few years. Never had any problems with it in +50k nautical miles over 10 years and only extra expense was that I did replace the bearings after about 6 years but that was because I had left them out under the boat when I had taken it all apart and the bearing races got a bit of rust and pitting on them so I decided to replace them all and all the seals. Worked flawlessly until we sold it in NZ at the end of 2016 and we stay in touch with that couple and the AutoProp continues to work very well for them. AutoProp Yacht Propeller Benefits Key benefits of the AutoProp as I see it are: “install it and forget it” propeller that gives you “automatic” variable pitch. Reverse is as strong as forward which can come in handy when you get stuck and really need thrust (ask me how I know?!!) Super simple design and build and the only thing more simple would be a fixed prop I guess. I can’t give you direct comparison numbers between the AutoProp on Learnativity and the fixed prop it originally came with as I replaced it with the AutoProp right away. But I would say that it definitely was more efficient in putting more power/thrust into the water and increasing the fuel efficiency. My best seat of the pants guess would be about 15% improvements. As for the LRC, I think an AutoProp could be a very good choice for all the reasons above; more efficient, automatic VPP, very low maintenance, etc. CPP Yacht Propeller If I had it all to do over again, I would still opt for a full CPP system and I have been very pleased with the quality of the Nogva so would go with them again as well. FYI, Nogva also sells full propulsion “packages” with everything from the diesel engine (choices of JD, Sania, etc.) all the way back to the prop so this might be a great way to go so have the full propulsion system coming as a complete package. Wayne Hodgins, mobius.world . Credit to Bruntons Autoprop and Mobius.world for use of their video, Nogva for the cover image. Read also: Yacht Maintenance Software Read also: Arksen Find their Groove Read also: Electrical System Design

No one likes to question their judgment; why should we when we are all possibly perfect? Such reflection could perhaps be used to create a few road signs, guiding others away from the same potholes? As we near the completion of our hull, it's time to do just that. Here are a few examples; there are plenty more where they came from. Forgive the artwork, "Dall-E", artificial intelligence, as in "a Redneck carrying a book.". Personalities I'll start quite close to home, understanding the characters in the play. I'm a bit impetuous, have a chronic dislike of detail, and am primarily unmotivated by finance, though, to be fair, it's a good measure if not a good reason for work. These are not the finest qualities one would seek in a project manager, so I avoid the role. My English vocabulary can also land me in unexpected trouble. All those colloquial words and phrases do not translate well across the Atlantic or to an overworked Turkish shipyard owner. So in dealing with matters procedural or commercial, it is best to stick to plain English and to follow up to ensure an understanding exists, "yes" may not mean "YES." Timing We had some excellent advice from a Yacht Broker early on in this journey. He intoned that if a couple has not previously sailed and wait until their mid 50's before starting, then it's probably too late to enjoy the experience. A good part of your life expectancy will pass just learning what it is you want or like. We had a chance at this journey 12 years ago when selling a UK-based company I had started some 20 years previously. Maybe I should have leaped and had a different life journey. However, here I am at 62 and just passed my yearly medical, so there is still time. But think about it, building a yacht is a time commitment. A few compromises might get you on the water far faster. As another example, we specified the navigation and communications equipment early in the build process. Comms seem to be changing by the minute. In the intervening time, both Starlink and OneWeb appeared on the scene. We now have both Iridium Sailor 4300 and OneWeb satellite communications systems. That's probably an unnecessary duplication and pending results with OneWeb; we may remove the Iridium system at some point. We could have avoided this by waiting until the last six months of the build timeline. Verification Did I say that Project Management is not my favorite sport? Our yard, Naval Yachts, has four or five builds in process at any time. Priorities shift, and there is a tendency to answer the loudest voice in the room. My mistake was believing in progress when it slowed to a near stop in the fall of 2022. That has probably cost us some four months on the project timeline. A time that is impossible to claw back so close to completion. The answer is to monitor more regularly in a " trust but verify " scenario. There is no need to shout, but make your voice heard regularly. Impetuosity The word always reminds me of a song from Walt Disney's Jungle Book. It manifests in need to do something in the belief that it's both justified and valuable. So I found an excellent instrumentation company in Belarus. They supplied four CAN Bus-enabled diesel fuel flow meters at a great price. Drop shipped to Praxis in the Netherlands for integration into the monitoring system. The only issue is that there is already a fuel flow rate signal in the John Deere J1939 engine CAN Bus signal, so they were unnecessary. $1200 of funds "down the pan". Be careful what you wish for. Delusion Believing one's own mantra is a minefield for the unwary, and just such an event happened with our steering system. What started as a simple idea became ever more complicated as features were added, and the scope of various suppliers became better understood. "Complicated" and "steering" should not be in the same sentence; it should not be that way. When one key supplier introduced late-stage change, the edifice crumbled, and complications became apparent because there was no easy, quick fix. I then compounded the mess by indecision and leaving our Owners Rep to try devising a fix. The solution was to take a step back from the detail and develop governing rules around what was needed. Only then could we logically reconfigure the components and obtain sign-off from all the contributing parties. Sometimes, we have to clean up our own mess . Expediency Vanguard will look different from all the FPB'esq designs; she does not have the iconic derricks used for paravanes and launching the tender. So the simple answer is to fit a knuckle crane like many other small commercial vessels. But think about it; they are heavy, something like 900kg on an already packed hull. Secondly, and perhaps scarier, at some point, Sebrina or our 14-year-old son, Rhys, will have to operate it. The crane cannot freely rotate 360 degrees, there is a lot of structure in the way, and one robust whack from a 900kg hydraulic crane supporting a 1,400kg tender will not be pleasant. We caught this one in time and researched further. The solution is now a 60kg reinforced carbon fiber derrick with a bi-directional electrical winch. Take time to think about more than functionality; consider how your selections will be misused in practice. Painting! We are painting the hull. Of the 18 FPB and now 14 Artnautica designs out there, only one is painted. Ours, Vanguard. Instead of hiding with all the fishing boats, I will now have to wash and paint a bright, shining orange hull and fret at the prospect of every scratch. My beautiful wife, Sebrina, has a skill set in interior design; I was reminded that it's her journey too. Love hurts but she will look nice. Chris & Sebrina Leigh-Jones We used to build custom homes on the US Atlantic Coast. I would often tell client that the short term trauma of a build will, in time, be replaced by the pleasure of ongoing ownership. Maybe I should listen to my own words?

I’ll offer my take on how to chip a cohesive crew from a group-of-people on board a boat. This is the first of a 3 part blog under the title's 'Acclimatise', 'Sail' and 'Lead' - ASL, aka A Sailor's Life. I learned far more from teaching than I ever did learning. Hmm. Hold on to that thought! Picture of a family trip preparing to leave to cross the Bay of Cadiz I was a civilian sailing instructor working with the Joint Services in Gosport, and on day one, I was nervous. I was relatively new to instructing and 5 young recruits from Sandhurst (UK Army Officer Training School) were my first lot aboard. Would I cut the mustard as a leader? We’ll see. I was aware they had standards they’d gotten used to. Could I sail? Till now, yes. So they came aboard and were sharp, witty and listened. In fact, I was more privileged than challenged. Civilian crews I’d worked with previously came aboard with a zigzag of personalities and standards. Between CEOs, vegans, the enthusiasts and the incompetent, it was a management juggle. Boats are inherently dangerous and running them requires order. The Sandhurst tribe nodded and responded with intrigue, and they ‘got on with it’. I saw organisation and, like a nerdy teenager with a chipboard, the valves to my dopamine stores snapped open. An encouraged leader's persona took over. Stage 1 - Acclimatise I call it such because joining a vessel is an environmental change every time, no matter your experience. New crews must: Meet the boat Meet each other Meet expectations Meeting the boat A boat is as much an ‘ice-breaker’ as it is a vital exercise, and I conduct it via the boring old inventory. ‘Get your heads in every cupboard, find every hose, every tool, find everything and talk, talk talk’ I ask. Similarly to pristinely polishing your boots, this builds a sense of ownership and care through self-extension. It’s vital. They also loosen their vocal cords and expand their awareness. Collectively they remember a lot. They’re becoming more ‘boat’. ( ‘be water my friend’ - Bruce Lee) Looking across Gibraltar bay, Royal Navy survey vessel HMS Scott in the background. Read also: Building Vanguard Read also: Interior Space of Our Explorer Yacht So, each other I’ve stepped onto boats as crew before, and as quickly as I could drop my bag I’ve been ordered to slip lines and we’re off. Now maybe that works for the brash extroverts, but I’m not that, and I was left for days after with a foreign feeling, like I didn’t know this boat, this trip, these people. So aboard my boats we start early with a cuppa and a chat. What I’m trying to understand as Skipper is what makes who tick. I don’t care much about qualifications but I care about how a crew will relate to each other out there. For half an hour we’re shell-cracking with our steaming brew props and seeing what comes up. Expectations are developing . Sorry but we’re still here talking, with our teas. Though I’m certain it’s important we are. Now as skipper, I’m on the tiller of this chat because otherwise, it can broach into banter and bullshit or awkward silence. Bring it back to sailing, sea, weather, team dynamics etc. I ask lots of questions. ‘What makes an effective crew?’, ‘What from your life/job skills will transition to sailing?’ Construction? - You’ll fix breakages. Nurse? Same, if we’re unlucky. Chef? Clean and tidy. Military? Comms. Every skill’s a resource somehow. What we’re doing is becoming sailors-in-our-heads, we’re leaving shore already. And I get someone to take notes. These notes are a bit of a trick, they’re really affirmations. They’re setting their own standards in their own words. And I keep the scrap of paper to hold them accountable to throughout their sail. Right, so we’ve gone from a bunch of strangers, and now we’re well into this boat, we’ve got ideas, we’re talking, we’re firing, we’re mixing. Let's talk next about sailing and leading. The development of the two among a team run in tandem, which I will try to explain in the next blogs. Acknowledgement: UK JSASTC Gosport Jeff Leigh-Jones That thought I asked you to hold on to, I'll add to it in the next blogs, but for now please teach us. Do you have your own ideas on acclimatising a crew? Or do you start elsewhere with a new crew?

Pioneered the Naval Architecture aristocracy of the yachting world, Steve Dashew and Nigel Irens, the era of the long lean rugged explorer yacht just expanded into another chapter. Naval Architect, Artnautica, has developed rugged seaworthy motor yachts with extreme passage and range capabilities covering 58, 65, 78 and 85 foot hulls. Each size is now a reality being either afloat or in construction. I count 9 vessels in this range, completed or under construction. For more details, read on! LRC 58 – 5 hulls in this class now sailing. LRC58-03 Britt is currently for sale, if you want to own and sail an LRC58 today. The fin-stabilised LRC58-3 Britt is available to travel the world, without the build wait . Details can be found  HERE .  A fifth, the twin engined LRC58-05 Aldania, has now been launched on April 20th in Hindeloopen, Netherlands ( photo above ). Photos of the build and the launch can be found HERE .  Aldania’s home port is Pula, Croatia. LRC 65 became a reality! We have two XPM78’s in existence. XPM78-01 Mobius The first was splashed in March of 2021, XPM78-01 Mobius including a custom made water jet aluminum tender.  She has been constructed at Naval Yachts . Single Gardner diesel engine rebuilt by the owner driving a Nova CPP.  Built for an adventurous couple with a lifetime of sailing under their keel.  The owners report regularly on their extreme expedition Passage Maker at their very informative site with link HERE . XPM78-02 Vanguard The second build to this design is under construction at Naval Yachts in Antalya Turkey.  The build started in May. Built to UK MCA Category  0 (unrestricted) standard, she is capable of safe, long-range operation worldwide under most sea and weather conditions. Vanguard is built to commercial standards including full redundancy of mission-critical systems. She is fitted with twin JD 4045 engines and hybrid electric drives backed by a large split LiFePO4 battery bank. Lastly, XPM85 just started construction. Read also: Interior Spaces of Our Explorer Yacht Read also: Designing an Explorer Yacht Helm Read also: Communication Options for Your Explorer Yacht

My day started early, 2.30 am to be precise, EST. Our Owner Rep, Akan, from his home is Marmaris Turkey, began by asking questions about the steering system. He is working through details of the engine room installation. Steering was now top of that list. Essentially, trying to understand thinking behind the system he's inherited and that predated his engagement. So, without pretending to be an expert on the subject, this is how it works. Wills Ridley - the importance of accurate steering. on the Corinth Canal, Greece. A yacht is pretty useless without steering, so we focussed on reliability. Following on from that was functionality. We wanted full Dynamic Positioning with dictated independent rudder operation as we have no stern thruster. It is potentially a complicated installation, so thorough commissioning was essential, and we wanted good local representation. Any system we installed would have to work within these three governing considerations. Firstly the steering gear itself, being the actuators and their controls. We looked at Kobelt and Wills Ridley . Both are well-respected suppliers of steering systems for commercial and military applications. We settled on Wills Ridley as we knew the local representative (Navantec) and trusted their input. The system supplied uses a dedicated pump, hydraulic system, actuator and huge cast alloy tiller head for each rudder. Pumps are provided with single phase 1.5kW power. Separate pumps and tanks are mounted on the same platform. Pumps may be run independently or in duty/standby configuration with auto switchover in event of failure with the duty pump. Rams are double acting and a single rudder can be disabled by hydraulically locking it. As designed, we achieve a >70-degree swing and a relatively rapid 10-second swing time, stop to stop. Emergency steering is also available directly from the control system in the engine room and acts on both rudders. Two jog buttons, a "left a bit, right a bit" sort of arrangement. Rudder control allows for duplex, simplex or Praxis Dynamic Positioning systems. Hydraulics are fully redundant and fast acting. Speed and force of operation are perhaps worth further discussion. Having spoken to quite a few old salts and Artnautica about it, we found Wills Ridley summed up the problem nicely. In a following steep sea, water on the rudder can act as if the vessel is in high-speed reverse, a.k.a; it flows in reverse across the rudder as the wave passes under the stern of the hull. The stern rises, the bow digs in, slows and "anchors" in the seaway. At this point, there is a tendency for the stern to swing out pushing the hull towards a broach. A fast-acting powerful rudder and reserve power will help keep you out of trouble. Steve Dashew's site also references this with some illustrative video studies taken on his FPB designs. We have two helm stations plus a docking station. Control from the helm uses commercial-grade marine Type Approved equipment from Praxis Automation. The helm has, FFU (Full Follow-Up *) and NFU (None Follow-Up *), autopilot / heading control*, and a Dynamic Positioning Joystick* function. We can trim, set toe in or out, set response speed and otherwise optimize steering functions. The rudders operate independently. The control system uses a duplicated, high bandwidth ethernet. For a further discussion of Vanguard's DP system, look HERE . Praxis rudder control system with two helm and one docking station. We have the physical end of the steering system wholly duplicated. We also have the control system duplicated and can operate either rudder independently at a push. At one meeting I did mention a backup hydraulic station at the helm but met with derision. Praxis was right; their system is Type Approved for the application and inherently more reliable than the backup we considered, times two independent systems. I still may fit one though! Read also: Visiting Praxis Automation - Part 1 Visiting Praxis Automation - Part 2 There are many ways to configure a steering system, and I would not claim that ours is better or worse than any other. This is not a new technology but it does present good and poor examples as documented in the various Marine accident reports . It is fully redundant, powerful and fast acting which is reassuring given our likely destinations. These features however, come at a cost in $$$ and complication. Time and tempest will be our dispassionate judge. Lucky for me, my wife, Sebrina, is very understanding, generally so if I delay asking until after the second glass of evening wine. :-) Okan Kuzu - Navantech Chris Leigh-Jones * FFU steering - the controller moves the rudder to the angle set. (like a wheel) * NFU steering - the controller continually moves the rudder whilst the level is activated, a jog lever. * Joystick - the controller produces fore or aft plus port or starboard motion on the vessel or any combination thereof. This is also provides the NFU steering function. * Autopilot - the heading controller navigates a given heading or course made good, it is also augmented to provide dynamic Positioning functions.

This our final Blog for 2022 following a visit to Naval Yachts. With Christmas now fading, my wife and I would like to wish you all a prosperous and healthy New Year. It will be an adventurous one for us as we take our last son out of school and begin our journey. Until then, we have to complete the build! Vanguard's build is now coming along well; we can judge progress by the type of questions the yard asks. This morning's salvo was a series of questions and suggestions for the instrument mast. Radar, Aerials, Lights, GPS, AIS ...... Rather than a knee jerk type answer, it was time to become a little analytical rather than simply judging on the prettiest version. This is how we approached the issue. Design Criteria The mast provides several functions and form, in this instance, must follow function. From holding the lights high to supporting the radar, communications aerials to the satellite, and flying the various courtesy flags. Each one of these has some unique requirements. To decide on the final configuration, we first listed what each requirement and it's constraints as repeated below: Navigation lights are required to satisfy COLREGS requirements; high up is good, and the Port and Starboard lights need to be separated as much as possible. Radar - we have 2 X Band radars to install. Each needs clear sight for 360 degrees with minimal interference from physical structures that reflect the beam. Additionally, they need to be high enough that the beam does not impinge on the forward flybridge roof. FLIR (illumination laser and IR and low light visible cameras) - need to be placed with a view of the bow and as high as is practical. Communications aerials - the flat aerials need to be out of the radar beam and with a clear sight of the sky within a 53-degree vertical cone. VHF/SSB - whip aerial needs to be as high as possible and separated. Lightning arrestor - need to be the highest of all. AIS/GPS/Fluxgate - need to be out of the way of the radar. Courtesy flag - we need to keep this up in the air! The Design Process So how did this process unfold? ​ First Design Final Design Nav Lights yes yes Radar no yes FLIR no yes VHF/SSB Whip yes yes Comms Aerial no yes Lightning Arrestor no yes AIS/GPS/Fluxgate yes yes The renderings below illustrate the first design drafted at the yard. Looks apart, we examined this against our requirements. The FLIR and Lightning arrestor were missed so an obvious fail there. The failure was ours in not being specific about just what equipment was to be fitted. That's is easily remedied. The Comms aerial was in part correct (Sailor 4300) but has omitted the OneWeb system, so we needed to correct that also. The major failure of this design is provision for the radar. We have primary and backup X Band Doppler Radar. They do not operate coincidentally. The mast is close to the rotating transmitter on this version and produces a substantial shadow to either Port or Starboard creating a blind spot in that location. Additionally, the beam would impinge on the flybridge roof (horizontal beam angle is 22 degrees inclusive not as shown in the illustration) resulting in an additional blindspot showing forward of the bow. Sat Comms Aerials have recently improved in weight and especially size. The new square flat units use a solid state phased array to track the various satellite clusters. These hand-off the signal from one aerial to another as the satellites move out of the detection cone (in our case 53 degrees or 106 included). To operate correctly there must be a clear view of the sky within this cone as shown in the enclosed illustration. We rearranged the solar panel layout to allow space for the Oneweb aerials at the front of the flybridge, clear of other obstructions and easy to access. FLIR - this is a large device, an ex military unit that we bought on an impulse. Height is useful but were also concerned with vibration, especially considering the optical and electronic magnification capabilities. Bigger picture, more obvious shake regardless of the subsequent added stabilization. We decided to secure the camera on the front of the flybridge deck/helm station roof. This means we have excellent forward vision but its limited to a 200 degree arc. Given we are more concerned about what is in front than behind, we can live with the compromise. We also messed around with the positioning of the aerials. Two VHF aerials were combined with a splitter so we can manage signals for both VHF and AIS from the single unit. The third was moved to a lower position so that the two aerials did not interfere with each other (like a. torch and mirror in their own spectrum). The SSB aerial is 4m, we positioned it on the flybridge pending later advice from the installer. There are three small vertical aerials on the aft edge of the flybridge roof. One of these is WIFI booster that pick up signal from the marina or wherever available and boost it. The remaining two are boosters for the onboard WIFI system on Vanguard herself. Lastly there was some concern of weight and windage being placed so high up on the vessel. We opted for an open lattice mast structure to minimize both. The basis is illustrated above though this design still requires detail engineering. No one is claiming credit for this as its similar to other Artnautica, FPB and Arksen designs. By removing a few retaining bolts, the mast can be lowered for maintenance.with assistance from the windlass capstan and a flew blocks. Read also: Communication Options for Your Explorer Yacht Chris Leigh-Jones My last paragraph is a constant thought when developing ideas for Vanguard, irrespective of the form of a design, can it be maintained thereafter and if so how? My introduction to this came as an apprentice. I submitted a simple fabricated gearbox design and was informed that although the design itself would work, it needed a suicidal Elf to fabricate it. All the weld symbols were on the inside!

When we take a small boat out into the expansive marshes of coastal South Carolina, help is simply a matter of calling on our ubiquitous smartphones. Woe betides the fool who thinks this strategy will work at sea. It's good for the first few miles and then - nothing. So what should we specify in this modern age of broadband connectivity and data streaming? Photo - sunrise over the May River, Low Country of South Carolina, USA (where phones work!) There is a pecking order to all this that we need to quantify. So let us remove the commerciality and assume connectivity can be rated as ( **** ) and operating costs similarly ( $$$$ ) Mobile Phone - ( * ) ( $ ) Cell phones will work in the marina and inland waterways, but you will be alone in all other locations. For communication when sailing, it's pretty useless and borderline dangerous. VHF - ( ** ) ( $ ) The ever-present standby where a novice may think disaster awaits him in picking up the mike to answer, but we all quite quickly get familiar with the background chatter. VHF will provide for all your ship to shore or ship to ship communications plus the emergencies within range but nothing more demanding of bandwidth. Reception depends on the height of your aerial and the distance to the recipient. So it's near the coast (< 20 miles) or another vessel. You can use this to transmit email and receive it similarly, but it is slow. Expect to be transported back to the age of the dial-up modem and leave Netflix alone. Long Wave SSB ( ** ) ( $$ ) Demanding hardcore sailors will be familiar with these systems and can receive over great distances with some practice. I'm not such a creature, so rather than repeat what I've read; we can stop at that point. Installation of the aerial takes some thought for the ground plane. We will fit an SSB but need to learn its uses better before blogging. Geosynchronous Satellite Comms ( *** ) ( $$$$ ) These are the Irridiums Certus and similar systems reliant on a small number of satellites in geosynchronous (fixed) orbit. Data transmission rates and coverage is typically much more significant than previous, and they cover polar regions. Expect to be transported back to the 1990s as far as baud rates for data transmission. Costs can be eye-watering for anything other than voice or textual emails so no date streaming or Netflix. Read also: An Instrument Mast for our Explorer Yacht Low Earth Orbit Satellite Comms ( **** ) ( $$/$$$$ ) These are the new boys on the block. The two familiar being Starlink and OneWeb. Both offer broadband connectivity similar too terrestial lines, but it comes with strings. Starlink initially locked its communications by location, but it now has a mobile version suitable for Recreational Vehicles traveling in-country. It has been implemented on yachts typically for coastal cruising but is only licensed to work is the USA at least when stationary and not underway ( this may change ). For example, a yacht plying the Amalfi Coast in Italy or PNW in USA/Canada and staying local. Their international roaming service costs are out of our league ( think superyachts ). One Web has a different business model. Install costs are a good chunk, but run costs are reasonable, especially if you also intend to interact with your business while afloat. "Costs" split $$ to run and $$$$ to purchase. These systems will interface with a smartphone via the vessel WIFI, one instance we'd suggest a smartphone may be useful on a yacht. We chose OneWeb or at least will fit it as soon as the new phases array aerials are available in early 2023. Starlink and OneWeb have coverage gaps that will reduce as additional satellite clusters are continually launched. Those gaps will be covered in the interim by our Iridium Sailor system. We purchased OneWeb through a distributor, OmniAccess, based in Majorca. They will also undertake the install so it looks like we will be stopping at Palma on our way out of the Mediterranean! If you want your communications systems to behave at sea as they do in your home, these low orbit satellite systems are the way forward and will only improve with time. Broadband has finally made it to the seascape. Chris Leigh-Jones I remember the 1970's when a call home was once every two or three months. A few hours wait to be patched through by Portishead Radio only to often have no one answer. In these modern times, I wonder if such immediacy goes hand in hand with a false sense of security on the open ocean? Useful links: Ernesto Esposito Sales Engineering Manager - OmniAccess Fixed +34 971221979 Mobile +34 608716463 www.omniaccess.com