Saturday, May 6, 2017

Streaming North: Discovering the Gulf Stream

Departure: May 1, 2017 @ 6:32 AM.

Following tradition, Darrel and Sue Peters joined us in the morning and helped us cast off. We met them in Florence Alabama in November of 2010 while on a Great Loop side trip. Sue left her pocketbook in the courtesy car and, having found no money in here purse (just kidding), we guessed that it was the folks on the 50 foot Ocean Alexander, returned the pocket book and have been friends ever since.

Back to business.

The Crew: Guy Aries, Les and Bob Benson
Departure from Sarasota is always a challenge as there is no easy way out to the Gulf. There are three options; Big Pass, New Pass and the Venice Inlet via the ICW, and each has its issues. Big Pass is a local knowledge pass that is tricky in calm water and dangerous with rough seas due to the shallow depths. New Pass, recently dredged, has a bridge with restricted openings before 7:00 AM and a very shallow channel leading from Sarasota Bay (where we almost touched last March) leading to the pass. Taking the ICW to Venice involves 4 bridges, two of which open every 20 minutes and numerous no wake zones.




Casey Key Swing Bridge
We chose Venice via the ICW on Monday morning as a brisk 20 knot wind out of the south was making 3 foot waves according to the forecast. That wave direction increased the risk of bouncing of the bottom at Big Pass. To shorten our time on this route we left at 6:30 AM to take advantage of the fact that the Siesta Key bridge opens on demand before 7:00 AM. The run to the inlet took two hours and 13 minutes.

When we entered the Gulf at Venice we saw that we had made the right decision as we immediately started pitching in a 3 to 4 foot head sea. Seas calmed to 2 to 3 feet as we passes Marco Island around 7:00 PM then increased to 4 to 6 as we progress toward the Keys. The 63 handled the seas well but pitching is not fun unless you’re playing baseball.

Around 4:00 AM on Tuesday morning we were 17 NM north of Marathon and the Seven Mile Bridge. Winds that had been 25 to 30 knots out of southeast winds reduced to 15 to 20 knots and the seas calmed.  At 6:27 AM, 24 hours after departing Sarasota, we crossed under the Seven Mile Bridge. We had covered 182 nautical miles at an average speed of 7.7 knots.

Seven Mile Bridge
Explanatory Note: The 63 cruises at 8.4 knots at 1400 RPM. The head winds and seas had reduced our speed by .7 knots. That may sound trivial but it’s not when you running 24 hours a day for multiple days. Essentially, you lose 16 NM and 2 hours every 24 hours.

Decision time. Run the Hawk Channel in protected water or run outside the reef in deep water to catch the Gulf Stream. This proved to be an easy decision as the forecast of south southeast winds at 10 to 15 knots with 3 to 5 foot seas was the same on both sides of the reef.

Would we get the promised push from the Gulf Stream? That question was clearly answered 4 hours later when we recorded an average speed of 7.9 knots. We were now seeing current speed readings of approximately 8.8 knots and, best of all, we were running in 3 to 4 foot seas off the starboard forward quarter. Those seas continued to calm (to 2 feet) and our speed continued to increase to 9.0 knots. The Gulf Stream was giving us a 1.5 knot push.

The depth increases as we cross the reef. Our position is shown on the right hand screen
Sorry for the poor photo 
The Gulf Stream turned Guided Discovery into a speedboat.  OK, I know. You think that’s a big exaggeration but you need to read on.

Written by Les

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