Envoy is wintering in Lefkas Marina, Greece, and we are home in New Zealand, returning 23 March.
The Jan/Feb issue of Passagemaker magazine has an interesting article concerning navigation and paper charts. They posed a question to a panel of recognised cruising gurus: are paper charts redundant nowadays with the array of GPS-based navigation aids? Perhaps surprisingly the over-whelming response was no, and that paper charts should still be used in consultation with electronics.
Particular issues highlighted were:
- easier voyage planning when you can usually see the entire voyage on a large scale chart and keep it in view.
- the ability to record regular position checks on your chart and retain this information in the event of equipment failure, or in the event of abandoning ship.
- insurance against the possibility of a Murphy’s Law equipment failure at a time when precise navigational information is required (this happened to us when our anchor dragged during a night storm in Turkey).
- the importance of eye-balling your intended course while cruising close-to-shore or in hazardous areas (for example many close-to-shore rocks and shoals aren’t noted on either electronic or paper charts, and in some cases their positions aren’t precisely accurate - we have found this on numerous occasions.)
- it’s not necessary to have a complete set of charts, just sufficient to get by in event of equipment failure. It’s also considered impractical to regularly renew charts or to correct them.
Aboard Envoy we always keep a particularly sharp lookout close-to-shore (e.g. within 0.25nm), use charts as a back-up when we have them for that area, and use the Cruising Guides as our hard copy when we don’t have charts, as well as for all harbours and anchorages. Although Cruising Guides always have a disclaimer stating they are not suitable for navigation, their level of detail for harbours and anchorages is generally greater than charts provide, and in the Med you get coverage of a whole country in one guide, whereas it would be impractical and cost-prohibitive to have charts for all areas of the main Med countries. Most Cruising Guides also have annual online updates, and we print these out for consultation. While night cruising or during daytime when we are away from visual land references (and with Med visibility this can be as little as 10nm offshore) we note down our lat/long at least hourly.
iPads
We initially purchased our iPad solely in case of failure of our laptop-based C-Map navigation system, but have found it terrific to have aboard - it fulfills our original objective, is now loaded with other useful cruising apps, is easy to take ashore to Wi-Fi cafes, can take reasonable photos and has multiple other uses.
We already described the Marine Traffic app in detail – see posting 13 March.
Although there are about three very good navigation apps, after talking to users and doing a bit of research we opted for Navionics. We can use this anywhere around or even away from Envoy, and it’s not hard-wired to the boat, so in the event of any power problem we still have a navigation system (at least until the iPad battery runs out). IPad versions 3 and later also have inbuilt GPS so they’re not reliant on internet or phone connectivity.
Laurie planning tomorrow’s cruise from the comfort of Envoy’s saloon armchair
On top of that an iPad is a fraction of the cost of having a conventional chartplotter as a back-up system (we wouldn’t consider using a tablet-based app instead of a conventional chartplotter as our prime system). We’ve found Navionics provides excellent chart detail and graphics, in many cases better than the version of C-Map we’re using, and chart updates are free. We have found Navionics (like C-Map) doesn’t show every close-to shore rock or shoal so usual caution and non-total reliance on GPS is required.
It’s very easy to change the chart scale using pinching and spreading or on-screen + and – buttons.
Your vessel’s position is indicated on screen by an icon with your current heading shown as a red line and your speed displayed. If you start a track, the ground covered shows as a yellow line and your average and top speeds are displayed.
View of Navionics on iPad
.JPG)
Some negatives are Navionics doesn’t show your current heading numerically, and doesn’t interface with your autopilot in any way. Neither is your lat/long continuously displayed, but can be found by placing a cursor over the vessel icon. There is also a lack of comprehensive user instructions although Navionics have a comprehensive FAQ section on their website.
Navionics allows you to measure the distance between any two points on the chart, create and edit waypoints, plot a track, display distance and time to go to reach your destination and automatically calculate and plot a safe track with multiple waypoints after you enter start and destination points.
If you load Navionics with your typical cruising speed and fuel consumption data it will display your estimated fuel usage to destination.
Units and several aspects of the display can be customised, for example a user-selected depth is shaded lighter blue to make shallower water areas more conspicuous.
The screen has a moveable cursor that enables the user to ask questions about any chart feature positioned under the cursor, and you can place an icon on screen with your own descriptive text attached. You can read other cruisers’ public comments posted to the charts, and if you are on-line you can post your own public comments, display photos or videos that either you or other cruisers have added, and overlay Google Map to view land features.
There are numerous other features that would be of interest to the more computer-savvy than we, and we definitely recommend Navionics as an additional and backup navigation system (of course without replacing hard copy backup).
The Jan/Feb issue of Passagemaker magazine has an interesting article concerning navigation and paper charts. They posed a question to a panel of recognised cruising gurus: are paper charts redundant nowadays with the array of GPS-based navigation aids? Perhaps surprisingly the over-whelming response was no, and that paper charts should still be used in consultation with electronics.
Particular issues highlighted were:
- easier voyage planning when you can usually see the entire voyage on a large scale chart and keep it in view.
- the ability to record regular position checks on your chart and retain this information in the event of equipment failure, or in the event of abandoning ship.
- insurance against the possibility of a Murphy’s Law equipment failure at a time when precise navigational information is required (this happened to us when our anchor dragged during a night storm in Turkey).
- the importance of eye-balling your intended course while cruising close-to-shore or in hazardous areas (for example many close-to-shore rocks and shoals aren’t noted on either electronic or paper charts, and in some cases their positions aren’t precisely accurate - we have found this on numerous occasions.)
- it’s not necessary to have a complete set of charts, just sufficient to get by in event of equipment failure. It’s also considered impractical to regularly renew charts or to correct them.
Aboard Envoy we always keep a particularly sharp lookout close-to-shore (e.g. within 0.25nm), use charts as a back-up when we have them for that area, and use the Cruising Guides as our hard copy when we don’t have charts, as well as for all harbours and anchorages. Although Cruising Guides always have a disclaimer stating they are not suitable for navigation, their level of detail for harbours and anchorages is generally greater than charts provide, and in the Med you get coverage of a whole country in one guide, whereas it would be impractical and cost-prohibitive to have charts for all areas of the main Med countries. Most Cruising Guides also have annual online updates, and we print these out for consultation. While night cruising or during daytime when we are away from visual land references (and with Med visibility this can be as little as 10nm offshore) we note down our lat/long at least hourly.
iPads
We initially purchased our iPad solely in case of failure of our laptop-based C-Map navigation system, but have found it terrific to have aboard - it fulfills our original objective, is now loaded with other useful cruising apps, is easy to take ashore to Wi-Fi cafes, can take reasonable photos and has multiple other uses.
We already described the Marine Traffic app in detail – see posting 13 March.
Although there are about three very good navigation apps, after talking to users and doing a bit of research we opted for Navionics. We can use this anywhere around or even away from Envoy, and it’s not hard-wired to the boat, so in the event of any power problem we still have a navigation system (at least until the iPad battery runs out). IPad versions 3 and later also have inbuilt GPS so they’re not reliant on internet or phone connectivity.
Laurie planning tomorrow’s cruise from the comfort of Envoy’s saloon armchair
On top of that an iPad is a fraction of the cost of having a conventional chartplotter as a back-up system (we wouldn’t consider using a tablet-based app instead of a conventional chartplotter as our prime system). We’ve found Navionics provides excellent chart detail and graphics, in many cases better than the version of C-Map we’re using, and chart updates are free. We have found Navionics (like C-Map) doesn’t show every close-to shore rock or shoal so usual caution and non-total reliance on GPS is required.
It’s very easy to change the chart scale using pinching and spreading or on-screen + and – buttons.
Your vessel’s position is indicated on screen by an icon with your current heading shown as a red line and your speed displayed. If you start a track, the ground covered shows as a yellow line and your average and top speeds are displayed.
View of Navionics on iPad
Some negatives are Navionics doesn’t show your current heading numerically, and doesn’t interface with your autopilot in any way. Neither is your lat/long continuously displayed, but can be found by placing a cursor over the vessel icon. There is also a lack of comprehensive user instructions although Navionics have a comprehensive FAQ section on their website.
Navionics allows you to measure the distance between any two points on the chart, create and edit waypoints, plot a track, display distance and time to go to reach your destination and automatically calculate and plot a safe track with multiple waypoints after you enter start and destination points.
If you load Navionics with your typical cruising speed and fuel consumption data it will display your estimated fuel usage to destination.
Units and several aspects of the display can be customised, for example a user-selected depth is shaded lighter blue to make shallower water areas more conspicuous.
The screen has a moveable cursor that enables the user to ask questions about any chart feature positioned under the cursor, and you can place an icon on screen with your own descriptive text attached. You can read other cruisers’ public comments posted to the charts, and if you are on-line you can post your own public comments, display photos or videos that either you or other cruisers have added, and overlay Google Map to view land features.
There are numerous other features that would be of interest to the more computer-savvy than we, and we definitely recommend Navionics as an additional and backup navigation system (of course without replacing hard copy backup).
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