Explorer Charts – Electronic Format
In July 2012 Jeppesen released a new version of its Bahamas electronic charts. Now available in both MAX and NT+ are EXPLORER-ONLY editions for chartplotters and PCs. If you want the more accurate and up-to-date Explorer-only version, make sure you get the latest issue which is currently September 10, 2013. You can order the chartplotter versions now from www.explorercharts.com. Go to the online store and click on the Explorer Electronic Charts category at the bottom of the page. There are c-cards for NT+ and MAX and SD cards for MAX formats. The model numbers are NA-M055.25 (MAX, covering the SE US and Bahamas) and NA-C391.35 (NT+, covering Bahamas only). For now if you want the PC versions order from Jeppesen @ 508-539-4366.
Jeppesen’s C-MAP NT+ NA-C 306.35 “The Bahamas”, MAX NA-M022.25 “USA East Coast and Bahamas”, and the new MAX local, NA-943.25 ($119.), September 2013 contain NO Explorer Chart data in the Abaco, Grand Bahama, Little Bahama Bank areas, and in the area east of the Crooked Island Passage, and the Turks and Caicos. These areas contain only chart data from another source. The remaining areas of the Bahamas are covered mostly by Explorer Chart data. We have found inaccuracies in some areas not utilizing Explorer chart data.
As far as other electronic versions with Bahamas data, Garmin Chartplotters with preloaded maps for all U.S. coastal areas, including Alaska and Hawaii, Charts for the Bahamas, now have Explorer Bahamas data only from Bimini to Long Island, but this data is covered over in some areas by NGA charts. The NGA charts are produced by the National Geospatial-Intelligence Agency and the coverage is for waters outside of the US. Where an NGA chart is available in areas at a larger scale than the Explorer Chart, the NGA is seen covering the Explorer Chart. In the affected areas the NGA data is usually older than Explorer data and sometimes omits important features shown on Explorer Charts. Some of the NGA charts in the Bahamas are based on surveys over 100 years old. We have advised Garmin of this problem and hope that changes will be made in future product releases. Before the Summer 2013 update most areas of the Bahamas were pure Explorer data on the Garmin products. Now, that is not the case with all areas on the Little Bahama Bank, which includes Grand Bahama and Abaco Islands, having data from another source. We have examined this data and found errors in some areas that could cause problems for mariners. We believe the other-source soundings in some areas show the water to be deeper than it actually is and correctly shown on the Explorer Charts.
In addition to the chartplotter and PC products, C-MAP by Jeppesen has recently released Jeppesen Marine Plan2Nav for iPad 1, iPad 2, iPhone 3GS, iPhone 4. This app is downloaded free and East Coast and Bahamas may be purchased from i-Tunes (the price varies depending on the device being used). The Bahamas portion of this product is similar to the multi-source versions described above with Explorer data only between Bimini and Long Island. The app charts are similar to the other C-MAP by Jeppesen products, but when metric units are used only the even meters rounded off to the lowest meter are seen. This can cause problems in areas of shallow depths. The app will work with internal GPS, wireless or cellular service for navigation, but was not found to be as accurate positionally compared to a stand-alone chartplotter. Since the charts remain on the device after being downloaded, it may be used for planning.
We continue to work with our electronic chart partners, Jeppesen and Garmin, to make Explorer Chart data available in as many products and formats as possible. In the past, decisions whether to include Explorer data in electronic products, unfortunately, have been made by management personnel not intimately familiar with Bahamas waters.
No Explorer Chart data is available in any Navionics products. It is important to use the latest Explorer Chartbooks printed charts and the latest release of Jeppesen electronic Explorer-only charts for the primary source of navigational information in the Bahamas.
The Explorer Team