Showing posts with label oracle. Show all posts
Showing posts with label oracle. Show all posts

Wednesday, April 27, 2016

Americas Cup Day Four Removal of Doubt

It was no surprise that Kostecki got the hook. Team Oracle has nothing if not a lot of depth on their bench and Ben Ainslie is certainly a qualified tactician. But it was also no surprise that they achieved the same result with the new guy. Oracle is sailing scared. If they get ahead of TNZ they are nervous that theyll get passed. If they get  behind, they have no confidence that they can pass. This sets them up for mistakes, and they have certainly committed more than enough to send the Cup back to NZ.

In race 6, Oracle won the start and the first run. But then they were so concerned about getting rolled that they failed to stick to a winning strategy. They went around the wrong mark at the leeward gate and that pretty much sealed their fate. Out of phase with the tide and their competition, they struggled to get back over to the right side of the track only to have TNZ pummel them all the way to the weather mark. By then it was over.

It was only a matter of time before TNZ would win a start. In race 7 they did that and simply never looked back. I dont know exactly how many practice days team Oracle has had, with or without Ainslie, but its pretty clear that they have not had the same amount as the Kiwis. It looks to me like the Oracle crew is still on the steep part of the learning curve while TNZ is certainly well beyond that stage. Perhaps Oracles crash last October took too much of a toll in terms of sailing days for the crew. Perhaps there is too much internecine friction within the command structure at team Oracle. Whatever it is, this team is not living up to its potential. The betting now is whether Team Oracle can win even one more race before the Cup is shipped to Auckland.

Friday, April 22, 2016

Americas Cup Day 3 Disaster for Oracle

It was a beautiful day on the Bay, with plenty of wind and lots of current at the start of the days racing. These were perfect conditions for the local boys to show the Kiwis about racing on San Francisco Bay. It was TNZs turn to enter the starting box first and they should have had the advantage, but Oracle was able to maneuver into reasonably good position just to weather of TNZ when the starting flag dropped. They accelerated faster than TNZ which was not able to establish an overlap at the first mark. Oracle looked good on that short reach, showing better straight line boatspeed and rounded clear ahead of TNZ. They maintained their lead all the way to the leeward mark. They came in on starboard tack with a comfortable lead and should have simply rounded the mark and hardened up onto a starboard beat and left it to TNZ to tack, and then keep a loose cover on them. Instead, someone in the back of the boat decided to round the mark and tack immediately. Disaster!

Anyone who has ever sailed a catamaran knows they are slow to tack. When you round a leeward mark you want to at least get back up to speed before you throw the helm over. Somehow, the brain trust aboard Oracle forgot this basic rule. So they rounded the mark and tacked all in the same maneuver, and in that moment they gave up their lead, Their thinking was that it was better to stay on the right hand side of the course to avoid the adverse current of the flood tide. Bad thinking. The first rule of yacht racing is to stay between your competition and the next mark. In a colossal brain-fade, the afterguard aboard Oracle ignored this rule and suffered the consequences. TNZ rounded the mark, hardened up on starboard tack and made short work of Oracles lead. At the first cross they were on port tack and ducked. On the next cross they were well ahead. After that there was no doubt as to who would win this race.

Ive sailed many thousands of miles as tactician and made more dumb moves than I can count, so I know how the crew of Oracle feels. In match racing it can be one bad move and your day is over, and if you still have several legs to race, that feeling of self inflicted wounds only grows. Oracle served this race up to the Kiwis on a silver platter and they knew it at the first cross, if not before. I can imagine the crew muttering under their breath as the were grinding in the sheets on that tack. Im sure the Kiwis were only too glad to snatch this race from the faltering grasp of the Yanks. It was so bad that Team Oracle decided to use their "postponement card" and skip race two today. Watching the body language on that boat, it was clear that this crew was demolished today, and it was probably a good decision for them to bail. Another pounding like that would have been devastating.

So the question is whether Team Oracle has it in them to come out on Thursday and make a race of it. I think this goes to the psychology of the game of yacht racing. Their boat is fast enough. Ive heard talk that its more complicated to sail than the Kiwi boat. Actually, all boats are more complicated to sail until the crew has practiced enough to make all the maneuvers look easy. If Oracle had another six months to sail the boat, all the maneuvers would go flawlessly. However, its possible that a demoralized crew can start thinking they are riding the slower horse and that can become a self fulfilling prophecy. If they dont fix that now, the crew will begin to expect the other guy to beat them. So the gang at Team Oracle needs to do three things if they want salvage this regatta:
1. Stop going the wrong way.
2. Keep the psychology of the crew from surrendering to defeat.
3. Make sure their strategy is one that can win, and make better tactical decisions.

Once again, I have to say that I am surprised at how tactics rather than simply nailing the start have been the deciding factor thus far in the regatta.


Saturday, April 16, 2016

Installing a Chain Stopper



A while back I installed a Lewmar chain stopper on the foredeck to make anchoring a bit easier. It was a simple job to fashion a mounting block out of teak, make a backing plate out of apitong and bolt it all together. The job was done in a day. Then I went out and anchored and discovered that if I left it as is, the stopper would soon knock all the galvanizing off the chain. This is a standard flapper type chain stopper, rated at 5,000 lb SWL and sized for 5/16 chain. I had used this unit on my last boat, which had 1/4" chain and a vertical capstan windlass, and it worked well. The problem is that there is barely enough clearance in the stopper for the chain to pass through, and only if it is perfectly aligned and set at an angle that matches the angle of the chain as it passes from the windlass to the roller. On top of that, the deck in that area is only about half an inch thick. It is made of a fairly heavy fiberglass laminate and a bit of wood core.  This isnt really enough structure to simply throughbolt the stopper to, so I added a carbon fiber top plate and a larger wood backing plate to bring it up to snuff. The photos below outline the process.


Mold. 

First I measured the amount of crown in the deck forward of the anchor locker. Its nearly flat but I wanted the edges of the top plate to fit tightly to the deck so I created a bit of extra curvature in the mold, which is made of a piece of old 1/4" Starboard.

Paper pattern with pre-cut carbon fiber

I took a template off the deck and drew the shape in AutoCad. I wanted the top plate to be fairly large so I could attach it to the deck with several widely spaced fasteners to spread the loads out as much as possible. The rectangular shape is the outline of the teak mounting block.

Laminating the carbon fiber
I used four layers of Vectorply C-LT2200 carbon fiber cloth for the laminate. This fabric is made of carbon fiber bundles aligned along the 0 degree and 90 degree axes of the roll and stitched together. This architecture is stronger than traditional woven fabric. The four layers amounted to about 88 ounces/sq yd of material for a total thickness of about 3/16" when it was finished.

Second layer is rotated 45 degrees 

I oriented the first and fourth layers so the fibers run at 0 and 90 degrees to the centerline of the boat and rotated the second and third 45 degrees to provide strength in all directions. I used WEST systems resin which works really well for hand laminating projects.

Finishing the top plate

After the plate was laminated and cured, I glued another copy of the paper pattern to it so I could precisely locate all the holes. It was a simple matter to drill and countersink them exactly where they need to be.

Top plate ready for finish sanding and paint




Check fitting the hardware

Finished part installed

I made a backing plate out of 1" thick apitong that extends out to the bulwarks to help spread the loads as much as possible. The 10" cleat allows for a snubber to be run out over the port bow roller. I found that if I take a turn around the roller with the snubber, it wont jump off if it when the boat swings at anchor.

Chain and snubber geometry works
It took a couple of tries to get the alignment and angle of the stopper to match up perfectly with the chain. It would have been nice to have a larger stopper, but there was just enough clearance between the shank of the anchor and the hatch for this smaller unit.

55 LB Rocna just fits




 

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