Meat of the Matter
Few SA’ers have the ability to get to the heart of a subject like ocean racer ‘Rail Meat’, best known for his great reports from far offshore on his Class 40 ‘Dragon.’ A recent Gear Anarchy inquiry from noob "climbon" about the kind of instruments to buy for a performance cruiser led to a comprehensive post from Rail that should answer almost anyone’s questions on instrumentation – ever.
If you do nothing but day sailing on local waters that are well known to you, you may need nothing at all. If you do local W/L handicap racing then maybe all you need is wind instruments. And if you plan on crossing oceans then maybe you need a wide range of stuff. What follows is a wide ranging over view of functions and some considerations you might want to think about. In the first part of the write up I tried to focus on options and issues without editorializing too much about my own opinions of specific manufacturers. The second part of the write up includes my own set up and some thoughts about choices between manufacturers. Keep in mind that I only know what I know… while I have used several manufacturers products and can have an informed opinion about their product, I have by no means used all the products out there and would be hard pressed to offer an opinion on some thing like, say, Tack Tick that I have never used.
Performance – Wind Instruments (speed and direction), boat speed & depth – These functions are sort of the table stakes for electronics. Valuable to racer or cruiser, this data keeps you safe, helps you do Dead Reckoning navigation, helps you understand what changes you might want to make to your sail plan, and helps understand how well you are sailing the boat. This range of functionality typically comes in an integrated set that includes anemometer, speedo (paddlewheel, electromagnetic or ultrasonic), depth gauge and display(s). It also involves a bus of some sort to transport the data between instruments. In more advanced systems that bus has processing power and can perform such functions as calculating true wind based on apparent wind and boat speed data. Several options have been listed here, including Raymarine, NKE, B&G, and Tack Tick. Furuno, Simrad, Northstar / Navico, and Garmin are also manufacturers. The two top end systems are clearly NKE and B&G, offering the sensors and buses that provide the highest quality data, at the fastest speeds, and with the greatest add-on functionality. Within each of those two manufacturers you have a couple of different price points and functionality points. Choosing between all of the different manufacturers and within a particular manufacturer’s product lines is a choice that should be driven by what your needs are, the reputation of the manufacturer and what your budget is. Another consideration is being able to get the data out of the system to use on a PC based navigation software program, Performance software program or Chart plotter system. Typically this means the nav instruments need to be able to take the proprietary protocol they use on their bus and translate it to NMEA for output (or input).
Performance Software – Performance software typically means the ability to load your polar data into the software and then use data about your actual performance versus your theoretical polar performance to figure out if you are maximizing your speed. If you are day sailing or cruising you don’t have much need for this functionality. If you are one design racing (where eyou have more direct means of judging your relative performance) or more casually racing, you don’t have much need for this. But if you are doing hard core racing at the top end of your fleet these tools can be very valuable. Top end instrumentation such as NKE or B&G allow you to do this right inside of the instrument bus. You can also get software that runs on a PC that can perform even more advanced and powerful analysis. What you will find is that the top end navigation software programs such as Expedition or MaxSea bake such capabilities into their software but you can get stand alone programs such as SA advertiser "Sail Clever" that perform similar functions.
Navigation – GPS – GPS solutions for the boat typically mean an antenna that is then connected to a navigation solution such as a chart plotter or PC running navigation software. There are lots of available antennas, and typically you will see that most chart plotting solutions will sell an antenna with their chart plotter. You can also take a third party antenna such as an Airmar antenna and feed its data into your solution.
Compass – Most electronic instrumentation needs bearing data. Nav software uses it to help calculate drift, instruments use it to help calculate true wind data, and radar sets use it to properly orientate signal returns on a chart overlay. Most autopilot solutions will provide some form of a digital compass, typically flux gate in nature. Also, you can buy third party compasses from Airmar, Furuno and others.
Charting Capabilities – Three choices here. If you are day sailing, nothing beats having the skills to be able to do paper charting. Second choice is to buy a chart plotter solution, which can range from a small self-contained hand held unit like Garmin might sell, up to fixed mount chart plotter systems that integrate GPS data from a separate antenna along with AIS data, wind and boat speed data and even radar data into a monitor that displays and overlays all of that information. Garmin, North Star, Raymarine, Simrad, Si-Tex all offer solutions in this space. The third choice is to feed all of that data (GPS, compass bearing, AIS, etc.) into a PC and run soft ware on the PC that offers charting and performance functionality. Options with this solution include Expedition, MaxSea and Nobeltec. My comment for these choices is that I prefer PC based solutions. A chart plotter solution is essentially a PC and software program bundled together. When you debundle the solution and buy your own PC and your own software, you can typically get better processing power, have the ability and option to upgrade hardware over time, can choose the best of breed charting functionality and can also upgrade more easily over time, and you can take your entire solution with you off of the boat if you load it all on a lap top. Chart plotter solutions are more "plug and play" and thus easier to install, but I think that the incremental work to put in place a PC based solution is far better in the long run.
Deck Access – One note here. If you have a chart plotter of PC, the question is where do you mount all of this. Mounting it below allows you to keep it safe from the elements and allows you to check things when below. But how do you see the data and information when you are at the helm? You either have to mount a monitor or display in the cockpit, or if you have a PC based solution you can use a remote, handheld deck screen of some sort like a Panasonic Toughbook. Performance data and instrument data are typically able to be seen on deck on the instrument displays. But having some means to be able to see the navigation, radar and AIS data on the deck is very valuable in difficult situations. Read on.