January 2009 Archives

This weekend Google released new imagery of the ocean floor in Google Earth.  It has higher resolution, and more accurate, representations of the underlying terrain.  The ocean floor is colored to reflect the terrain features of the sub-sea surface. The new rendering is a bit higher resolution (much higher in places) and is presumably more accurate than the previous version. According to the copyright messages the new ocean floor is coming from "SIO, NOAA, US Navy, NGA, GEBCO". These entities are dedicated to getting the best ocean floor surface data they can. You don't have to do anything special to see the new ocean floor, just open up Google Earth (it's not visible in Google Maps yet). Unfortunately, the new ocean floor in Google Earth is NOT 3D - yet. This could be the first part of the release of new data for the rumored "Google Ocean".

Unfortunately, Google has ruined some of their own previous data by actually covering up some imagery of remote islands and atolls with the new ocean floor imagery.  Not only that, but their selection process has covered satellite/aerial imagery of shallow waters like those in the Bahamas and around island chains.  This is particularly bad news for boats, divers, fisherman, and others who value being able to see the waters around important places around the world.  For boaters, we can use the visual imagery to see changes in water color which help identify shallow areas, locations of reefs and undersea obstructions, and the location of boats at anchor (indicating good anchorage locations).  I'm hoping Google will listen to the feedback and re-instate missing island imagery and more waters with visual imagery instead of bathymetry.

On Saturday, I invited my brother and his family to come down to the boat for a sail.  The weather turned out near perfect.  We had light winds in the morning, but it was expected to pick up to the 10-15 knot range in the afternoon.  And, the temperature was going to be in the low 70s (F).  Not bad for mid-January!

Using GPSVisualizer.com I've colorized our GPS track of the sail according to the speed of the boat.  If you load the track in Google Earth , you'll see a legend on the left of our speed.  I've also added some placemarks describing where we raised sails, had wind change, etc.  I may have to think about a way to recording wind speeds when we are visualizing our tracks for the circumnavigation.

We started out at about 11 AM and motored down the St. Marys river out to sea.  I timed it so we had the tide going out when we left, and tide coming back in as we returned.  The winds were less than 5 knots at the start, but once we got out a couple of miles the winds picked up to a little over 7 knots.  So, we turned into the winds and raised sail.  There were a few other sail boats a few miles out.   Once we were making way, we had some lunch.  The boys had a great time running around the boat and playing like they were pirates.

There is a right whale protected area about 12 nm out.  A cargo ship was headed around the protected area to go in the inlet to Fernandina Beach.  After he passed, we turned around to head back in.   The winds gradually picked up as we neared the inlet.  The direction of the wind was perfect and we managed to sail most of the way back up river towards St. Marys.  We dropped sails at the sharp bend to the south in the river.

As we headed to the marina, the dockmaster asked if we could park in a different slip. We had already set up our fenders and docklines on the other side of the boat, so we had to turn around a couple of times while we re-arranged. We pulled into the new slip and got some help from other boaters with our lines. Fortunately the power line just barely reached the power outlet near the starboard bow. My brother John and I watched the moon rise over St. Marys. It was a perfect end to a perfect day of sailing.

Got up early to prepare for some runs with out new dinghy "Coconut".  The dinghy is a 12-foot Apex Inflatable with hard bottom with a 25 hp Yamaha outboard motor. The first project was to drill the hole to pass the fuel line into the anchor locker .  The 6 gallon gas tank fits nicely in the anchor locker with enough room left over for the anchor and rode (once I get one).

Spent a few minutes setting up to lift the dinghy back into the water (we keep her stored on the back platform of Tahina).   For lifting/lowering we have a really cool setup with a sliding derrick in the boom which has two pulleys on the end.  The 2:1 main halyard lines go from the top of the mast over the end of the derrick pulleys and then hook to the lifting harness I build last month for Coconut.  We have a rope at the other end of the boom (near the mast) which pulls out the derrick so you can get the boat over the water.  However, last month we realized the derrick is about 1 to 2 feet short of the length required to get the boat past the aft transom of the boat.

Here are some photos showing Coconut up on deck, the deck mats, and Coconut in the water:

Once I had Coconut lifted up, and the derrick out as far as possible, I worried about how to keep it pushed out from the transom so I could lower it.  I ended up sticking the mop handle in a slot on the edge of the transom. The mop handle kept the dinghy pushed out just far enough.  I began lowering and the dinghy went down just fine.  With another person, this will be easier since they could simply push it out slightly.  But, I will most likely have many times where I'm dropping the dinghy alone.  I really want to get the derrick set up so it goes out another foot or two!

Once Coconut was in the water, I put away the derrick and halyard.  Then I got things ready for a break-in run.  I had a bit of difficulty getting it started with the rope lanyard.  But, once I squeezed the fuel bladder a few times it finally got enough fuel to start.  I let it run at idle for 10 minutes per instructions in the manual.  Then I took it for a few short runs at half-or-less throttle.  This needed to be done for 50 minutes.  The good news is that this boat planes quickly (without too much throttle needed) when only one person is on board.  And, it was plenty quick at even half throttle.

Later in the day, after it warmed up some, I took Coconut on a longer run at higher speeds (again staying within the manual recommendations).  The first 10 hours of engine use are constrained a bit.  But, I did notice this boat reaches its top speed well before full throttle with only one person on board.  I suspect the boat is going 5-10 knots faster than we did at full throttle with the 15 hp motor we had on our earlier dinghy (same model/manufacturer dinghy).

Of course, I took my handheld GPS with me while doing the trial runs. You can see the dinghy trial runs in Google Earth. I used GPSVisualizer.com to colorize the tracks according to speed (in knots). Toward the end of the trials I did I was allowed to briefly open up the throttle. It looks like Coconut tops out at a little over 25 knots with just one person on board!

Karen needed to stay home, but I decided to go down to Georgia and visit Tahina.  I had some specific goals for this weekend:

1. Get the new dinghy in the water and begin the break-in process for the new Yamaha 25 hp engine.
2. Drill hole to put the fuel tank for the dinghy inside the anchor locker.  Needed a 1/2 inch hole for the fuel line to go through.
3. Get painters (boat lines) for the dinghy.  We use two so the boat can be attached between the hulls and stay in position without the dinghy motor hitting the hulls.
4. Get an anchor and rode for the dinghy
5. We had a problem with the water pump for the starboard heater.  Try to find the problem.
6. Take my brother and his family out for a sail this weekend - weather forecast looks good.
7. Examine the boom derrick for the dinghy to see if it can be extended further.

I left about 9:30 from Raleigh and drove down to St. Marys.  It took a good portion of the day to get there.  But, I still managed to arrive before dark.  I looked over the boom derrick, but could see no obvious way it could be extended.  It does seem it can be unscrewed and maybe removed from the boom.  I determined the size drill bit needed and bought one at the hardware store.  Also bought some gasoline for the dinghy so I'd have enough for the break-in runs.  Tried starting the starboard heater, but the water pump still is not working right.  Had plenty of blankets, so I didn't worry about it for tonight.