A trap for the unwary. I don't know whether it is a bug in OpenCPN (both V5.0 and 5.2) or some other data issue.
I have encountered an issue with a cancelled cell being displayed in OpenCPN, rather than the replacement cell. The issue occurs with AusENC in the Lakes Entrance (Victoria) area.
AU5182P2 is the large scale chart of the area, which has been cancelled.
AU5LEN01 is the replacement, updated, chart for the area.
In the Week 32 update issued on 8-AUG-20, both cells are listed in the PERMIT.TXT file and the PRODUCTS.TXT
When I load the updated permit and updates folders and
rebuild the chart database, both cancelled and replacement charts appear in the 'piano keys' but the cancelled chart is displayed. The
images below show the first
screen (cancelled cell displayed) and, after selecting the second 'piano key', the replacement cell. If you look carefully, you can see a new No-Anchoring area in the approach to the Entrance.
Advice from the Aust Hydrographic Office is that:
"When a cells is cancelled the old cell is not automatically removed from permit files. Some systems allow the customer, if they wish, to view both old cell and the replacement. "
OpenCPN certainly allows the user to view both files, but there is no warning that what you are viewing is outdated.
There is provision in S-63 for the replacement cell to be included in the PRODUCTS.TXT
record for the cancelled cell, effectively tagging the old cell as having been replaced. The AHO does not include this in their PRODUCTS.TXT file. There must be some other way of communicating to display software that a cell has been cancelled, which OpenCPN is not using.
This issue may be caused by the fact that the replacement cell is not just a new edition with the same cell name.
The workaround is simple: delete the line for the old cell in the PERMIT.TXT file. But the problem is knowing when you have outdated data on your
screen when everything is telling you that it is up to date.
Regards,
Andrew