He Said…

“Come sail away with me,” he said.  

“It will be great fun and very romantic,” he said.

“We will travel to exciting and exotic places,” he said.

“We will travel in high style on our yacht,” he said.

“The world will be our oyster,” he said.

He did not mention the bilge cleaning…

She is way cuter than Ed Norton…

On an Amel the bilge doubles as a gray water sump.  All of the sink and shower drains flow into it to be pumped overboard. So soap scum, kitchen grease, and other assorted debris accumulate over time and need to be cleaned out.  It is a totally yucky job.  And that is how we spent our day today!

A Global Positioning System Mystery

Yesterday, we solved a mystery.  Our main navigation computer has had an odd problem since before we left the Chesapeake. It no longer knew what the date was.  It was reporting that the date was in March, 2099. Position, and the time of day were right, just the date was wrong.

This confused me to no end, because the time and date come from the systems internal GPS chip.  I know that to accurately determine position the GPS needs to know exactly (to the microsecond) what the time is, so I thought that MUST be correct. I was convinced that the problem was that one of the several new devices we added to our system was confusing things. Turns out, I was wrong.  After struggling with this for several days trying to fix it, I turned to Google and ran a search for this particular problem.  It seems I am not alone…

The GPS satellites report the date with a counter that increments every week. In early October that week counter reached 1000.  The manufacturer of the GPS chip that is used in our system apparently did not allow memory space for a three digit week, and they all stopped reporting the correct time and date on that same day. This type of chip is used in many different devices, all of which lost track of the date at the same moment. Ooops.

Many of our electronic navigation systems need to know the correct time and date to work properly.  We solved most of the issue by adding a standalone GPS to our system.  Mostly.  There are still some funky issues that I have managed to find workarounds for. 

There is a lesson here.  In this case, a software bug only affected the date, not the time of day, or the reported position.  The next time we might not be so lucky.  A similar kind of failure could totally disable the electronic systems we rely on for telling us exactly where we are.  Knowing how to use a paper chart and traditional navigation tools IS still important.

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