The 7 Best Marine GPS
7. Raymarine Dragonfly-5M
- charts load instantly
- updatable navionics software
- no sonar capability
|Rating||4.2 / 5.0|
6. Garmin GPSMAP 78sc
- 20-hour battery life
- includes basemap
- hard-to-read screen
|Rating||4.2 / 5.0|
5. Lowrance HDS-7 Gen2
- extremely accurate gps
- includes structure scanning
- watertight case
|Brand||Lowrance HDS-7 Gen2|
|Rating||4.0 / 5.0|
4. Garmin GPSMAP 7608xsv
- garmin marine network support
- 10 gps refreshes per second
- wi-fi and ant support
|Rating||4.1 / 5.0|
3. Simrad Go7 Xse
- connects with nmea 2000 engines
- wi-fi and bluetooth
- 2d sonar for shallow waters
|Rating||4.8 / 5.0|
2. Raymarine c95
- fast dual-core processing
- composite inputs for marine cameras
- syncs with ios devices
|Model||c95 w/Lighthouse Charts|
|Rating||4.5 / 5.0|
1. Garmin GPSMAP 547
- gps and glonass support
- worldwide basemap included
- ipx7 certified waterproof
|Rating||4.7 / 5.0|
The History Of GPS Navigation
The Global Positioning System (GPS), was originally created for military and government intelligence applications. It is a network of satellites that orbit the Earth in fixed points and beam signals down to anyone using a GPS receiver, no matter where on the planet they are located.
In 1957 just as the cold war was becoming more intense, the Soviet Union launched Sputnik, the world's first artificial satellite. This motivated the United States to allocate more money towards their own satellite project and, in 1960, the US launched their first satellite system known as Transit. Transit consisted of five satellites and allowed US Navy ships to take a reading on their position once every hour.
In 1967, Transit was replaced by the Timation satellites, which featured extremely accurate atomic clocks. The more accurate a satellite's clock, the more accurately it can determine a GPS receiver's location. Between 1978 and 1985, GPS technology experienced rapid development with a total of 11 new satellites being launched.
When the Soviet Union shot down a Korean passenger jet in 1983, the Reagan Administration decided that GPS was needed for civilian applications as well. This would allow them to accurately determine their location and reduce the possibility of straying into a restricted foreign territory.
In mid 1993, the US launched their 24th Navstar satellite thus completing the modern 24 satellite GPS. At any given time 21 satellites are used to fix a GPS receiver's location while three satellites are spares in case one of the satellites malfunctions. Currently, the European Union is creating the Galileo GPS system which will use a total of 30 satellites, 14 of which are already in orbit.
Why Navigation Is So Important At Sea
Marine navigation is making the marine transportation world safer and more efficient. It is easy for landlubbers to believe that GPS navigation is only a necessity when large ships are out at sea with no land in sight to use as a reference, but this isn't true. GPS make navigating congested waterways and harbors safer. In fact, GPS navigation is more critical as large ships pull into port, when the risk of crashing into other ships and hazards is elevated.
When looking at the numbers, it is easy to see that GPS navigation has made the seafaring world safer. Between 1994 and 2010, as the use of GPS became a standard on most ocean going vessels, the total loss of ships over 500 gross tonnage has come down from 180 per year to 60 per year. High value accident claims have reduced from 520 a year in 1990, to 200 a year in 2010. And perhaps most importantly, the number of lives lost at sea annually has decreased from 450 in 1995 to 250 in 2010.
Environmental repercussions have lessened as well. The use of GPS is also responsible for reducing the amount of oil spilled at sea as a result of vessel crashes. In the 1970s, there was an average of 22 major oil spills a year from ships and, in 1993, roughly 140 million tons of oil was spilled from ships. In 2011, only 1,000 tons of oil was spilled. This increase in safety and lessened environmental impact has come even as ocean trade continues to grow.
Picking A Marine GPS System
Marine GPS units come in all shapes and sizes, which can make picking the right one difficult for those new to using them. Before choosing any GPS unit, it is best to consider a few important factors. First check the manufacturers specifications to see how many satellites the device uses. Low cost models may only use 12 satellites, which is enough to function properly, but a 24 satellite system will be notably more accurate.
Next, one should consider if they prefer a handheld unit or one that gets mounted to the boat's dash. If you have a small John boat or dinghy, a handheld model is probably sufficient. But it can be difficult for some to read the screen of smaller units and they also generally have reduced mapping capabilities.
Larger mounted GPS receivers are good for those who like looking at a large, color screen and want to see a lot of details about the surrounding area. Many are also compatible with a fish finder and depth sounder. Those with sailboats and larger yachts that carry a dinghy will often require both types. The handheld model being vital in an emergency when the larger vessel must be evacuated.
Depending on how you want to add new maps to your unit, you may want a model that can be connected to a computer. This allows one to download new maps and transfer them directly to the internal memory of their GPS. Models that don't connect to a computer will require the user to buy cards which have maps of particular regions of the world.
Some marine GPS systems, particularly handheld models, are considered non-mapping. This means they show a compass, latitude, and longitude to help you determine your position, but not an actual map. If you want to see a map displayed on the screen, choose a mapping system.