Instruments
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Instruments
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BASIC INSTRUMENTS: - NETWORKING When we equipped Shaula3 we did not bother too much about the possibility to network all instruments, with the only exception of the two chart-plotters where the network connection was essential to be able to share the same chart cartridge and the same radar information between the two devices. Some of the instruments already installed - including the autopilot - were from Raymarine, so it only seemed logical to stay on a Raymarine solution also for the new instruments. Several years have passed, and now the possibility to connect ALL instruments in an high-speed network has become commonplace, and this allows to simplify the instrument set, taking advantage of the new multi-function displays which can be customised to show data in a series of screen layouts. We opted once again for Raymarine instruments, with which we felt familiar. Unfortunately, the Raymarine technological evolution is a work-in-progress, with 3 different network architectures: seatalk, seatalk ng (new generation) and seatalk hs (high speed), and the available devices are still not standardised on just one solution, practically imposing to use all three, which is not good for on-board-system simplification! - LOG/DEPTH/WIND
Night vision: can you see the dials? On Shaula3, instruments were on the console as well as on the steering column On Shaula3 we had the "classic" 4 instruments:
We also had a "tri-data" display under-deck to serve as a data repeater near the chart table, and after the first season's experience, we also added a wind direction display on the steering pedestal for better visibility at night (the dials on the console-mounted instruments turned out to be totally unreadable at night!). A total of 6 displays, and always powered!! (the Raymarine displays of the time could not be turned on or off individually) Over time, we realised that all the information provided by the dedicated displays were also visible on the chartplotter's screen as well as on the autopilot's control head, so when equipping Shaula4 we determined to drastically reduce the number of displays.
Raymarine i70 Multi-Function Display Installation in Shaula4's cockpit The new Raymarine series 70 Multi-Function Displays can show a number of screen layouts, all customisable at will, where it is possible to concentrate the most relevant information, depending on the moment's priorities. Just ONE display, placed in the cockpit (the other one is the Autopilot Control Head), and all info which are flowing through the network are available for viewing! - GPS:
The advent of radio-navigation systems during the last 30 years has completely changed the way of handling navigation: gone are the times when one had to spend half an hour working with a sextant and the nautical tables (assuming the sky was not covered by clouds!) or fiddle for several minutes with the directional antenna of a radio-direction-finder to obtain a fix which was accurate to few miles at best, or plot a position on the special LORAN charts if one was rich enough to afford one of the early Loran receivers. Especially when sailing short-crewed, we strongly believe that the ability to get a position fix in few seconds, with a precision that today is down to few meters, is an important safety factor and that there is no excuse to not take advantage of what the technology is offering us. Both on Shaula3 and Shaula4 we found already installed a good GPS receiver, which we obviously kept as an emergency spare GPS in case of a failure of the main one, connected to the chartplotters. On Shaula3, it was an MLR set which served us faithfully throughout the voyage (even when half-full of seawater!) while on Shaula4 it was an excellent Furuno GP31. (And yes, we also have a sextant onboard - actually, two sextants! - plus all that's needed to take a fix "the old way" in case of a catastrophic system failure or to just confirm the instruments' accuracy, but we never had to resort to these, not even after the capsize, when a spare battery-powered GPS guided us to safety) - CHART-PLOTTER: We are in the 21st century since a while now, and the price of
chartplotters has decreased significantly, besides the many smartphone or tablet
Apps which are now available at an even lower price: nowadays there really is no
reason to do without the convenience and safety provided by the ability to have
an interactive nautical chart in front of your eyes, showing your position and
(if radar or AIS are available) the position of other vessels and obstacles.
The old Raymarine RL70CRC on Shaula3..... ...and the brand-new Raymarine e7 on Shaula4 On both boats we opted for a chartplotter selected from Raymarine's range which offered the capability to be networked with another display in the cockpit, sharing the same charts and Radar data (unfortunately this is not possible on cheaper models). Why TWO chartplotters? Because there are TWO places where a chartplotter is useful: one is under-deck, at the chart table, mainly for waypoint and course planning in front of paper charts, pilot books and any other info, while the other is in the cockpit, just in front of the helmsman, usefull mainly for the radar screen when sailing offshore, and to consult small-scale charts when navigating close to shore and there are only two people aboard, one at the helm and the other on the foredeck handling the sails or preparing to anchor. We are so accustomed to this way of navigating that we would rather do without the screen under-deck, if forced to make do with only one display. For Shaula4 we actually did consider doing without a second chartplotter in the cockpit, using to this purpose an iPAD loaded with Raymarine's remote control App which would connect via wi-fi with the chartplotter under deck and replicate the screen and all commands on the tablet. Very handy, but unfortunately it turned out to be very erratic, losing connection at the worst possible moment and then not being able to reconnect quickly; we will try again after having brought everything at the latest software release, but in the meantime we bought a second Raymarine e7 MFD to be installed on the roof-top. And what about using a PC or Tablet for navigation, instead of a chartplotter? We did consider this option, but in the end voted against. Read this page for further info. - RADAR:
Is radar really needed on a small boat? It's certainly a luxury, both due to the price and the power requirements, but there are situations where radar is an important security aid, such as:
Not essential then, but certainly useful! On both boats we opted for a Raymarine Radar which could be connected to the chartplotter display; this offered the additional benefit, compared to a totally stand-alone solution, to be able to super-impose radar pictures to the nautical chart, which can be very useful during pilotage situations (especially if the chart is not very accurate!).
Example of radar screen: all those dots in the right half of
the screen are ships at anchor, while at the bottom you can see a ship under-way
(the velocity vector shows it's moving from left to right). - AUTO-PILOT: On a short-crewed long-distance-sailing yacht an electronic autopilot is absolutely essential! Full stop. No discussion. During manoeuvres, it's like having one more person on deck, and during passages lasting more than few hours it's an important contribution to the crew's ability to rest. Besides, it handles the boat better than many humans!! When a crewmember is alone in the cockpit and the other is under-deck asleep, the auto-pilot allows performing simple manoeuvres without having to wake the poor fellow who's taking a nap, but also when both are on deck, it avoids that one of the two is stuck at the tiller (for example when reefing the mainsail, one is at the mast and the other can handle the cockpit-led lines, while the boat sails for itself).
The new "EVO 100" autopilot installed on Shaula4 and its control-head In fact it's so convenient to use the autopilot, that we almost never steer the boat, even during coastal navigation!
When using the auto-pilot as an help during manoeuvres, its very handy to have a REMOTE CONTROL allowing to make course corrections or even a full tack while being ready at the sheets. Unfortunately the old-fashioned remotes, which were just a box with few buttons and connected to the pilot by wire, have been replaced by sophisticated wi-fi devices which are in fact a full control-head (and cost like one!). On Shaula3 we had one, which was very handy but needed to be left on its charging cradle most of the time because the battery was lasting very little time; for the time being we have bought nothing for Shaula4, we are holding any decision after some experience with the full instrument configuration. Obviously there is the option of a
wind-vane instead of an electronic autopilot, with the obvious benefit that a
mechanical device does not need any electricity to work (and an electronic pilot
needs plenty!!) but has the drawback of being slow to set-up and obviously
useless when motoring. Conversely, an electronic pilot starts
at the touch of a button, and on the more sophisticated models it can be used
also in "wind-vane mode" instead of simply following a compass course. On Shaula3 we had both: a wind-vane which was used during the long passages under sail, and an electronic pilot which we used when motoring and quite often when manoeuvring. This combination worked passably well, but we realised that during the voyage we bothered less and less to rig the wind-vane. As a matter of fact, the majority of the Blue Water Rally boats did not have a wind-vane at all! On Shaula4 the question is moot, we are not planning long passages that would possibly justify the expense for a wind-vane, while we bought a good Raymarine pilot; unfortunately it was not possible to install an hydraulic actuator permanently connected to the rudder, like we had on Shaula3 (which allows to engage and disengage the pilot at the touch of a button) so we will have to make do with a classic electric tiller arm, more exposed to damage and requiring to be physically connected and disconnected from the tiller. BATTERY MONITOR: On moder yachts, equipped frith refrigerator, autopilot and assorted electronic instrumentation, the requirement for electrical power has drastically increased over the last few years. As a consequence, monitoring the charge-status of the battery bank and the rate of charging from the various sources (engine, battery charger, solar panels, wind-generator, etc...) has become very important. Since some years several devices have become available for this purpose, with varying functionality and cost.
On Shaula3 we found an instrument from French company Thyra, good but it failed when we capsized due to seawater flooding. We then replaced it with an instrument from the British firm NASA, and on Shaula4 we installed the same device. To be fair, there are better products on the market, but this
one is one of the cheapest and we find it to be adequate for a boat like ours,
with relatively simple systems. Continue reading at the page concerning Communication Systems
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Webmaster: Gianfranco Balducci - email: gfbalduc@tin.it Last Update: 07/09/2017
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