"Thom Stewart" wrote ...
Scott,

You've seem to have forgotten "The Gulf Stream Master" Jax. I'm sure
he
can help you ride the eddies:^) Maybe even find you a stray current
heading south (g)

Not forgotten, simply ignored.



Now, for what's it worth. The Tide Flow is a sine wave. Us common
folk
understand that slack water is at the top and bottom of the wave. So
slack is, roughly about a hour and it is roughly in the upper 30%
counting the end of the rising tide and the beginning of the Ebb.
15% to
the HW and 15% roughly to the Max Flow. That means about two hours
to
max flow, 8 hours of max flow and then another couple of hour of
diminishing flow to LW.

That doesn't make allowance for land masses, rivers, depth, etc.
Also
the time differences of where the HW takes place. So if you are
sailing
a Riding Tide you can increase your Max Flow by watching your
location
and tide tables times.


Thanks, Thom.

Scotty

"Thom Stewart" wrote in message
...
Scott,

You've seem to have forgotten "The Gulf Stream Master" Jax. I'm sure he
can help you ride the eddies:^) Maybe even find you a stray current
heading south (g)

Jax also insisted that the time of high water and slack current must be the
same, to be otherwise would violate the laws of physics (on his planet).





Now, for what's it worth. The Tide Flow is a sine wave. Us common folk
understand that slack water is at the top and bottom of the wave. So
slack is, roughly about a hour and it is roughly in the upper 30%
counting the end of the rising tide and the beginning of the Ebb. 15% to
the HW and 15% roughly to the Max Flow. That means about two hours to
max flow, 8 hours of max flow and then another couple of hour of
diminishing flow to LW.

While the current flow in "simple harbors" may follow a sine curve, in cuts
between two bodies of water the flow is different. The curve is more
"squarish," that is, the flow ramps up quicker and stays high longer. The
duration of slack is reduced. The best example is Hell Gate in New York.

IIRC, the flow rate is proportional to the square root of the different of
height of the two bodies.

Jeff,

You're not telling the full truth with "Hell's Gate" are you? You are
leaving out the River flow. That is a constant and mentioned as a
variation to Tidal flow. There are many variations on Tidal flows,
including the Moon, which causes abnormal high and low tides. When
coupled to large bodies of water constricted thru small inlets the sine
wave will be knocked for a loop. Much like a clogged drain on a sink.
LIS has its share of them. The Narrows, Plum Gut, Fisher Island to name
a few. Every place in the World has its' variations, the higher the
Latitudes, the greater the number. Fundy, Solvent, Gibraltar, Georgia
Straits, Cape Horn, etc. The list is endless but local knowledge has
learned to handle it. That's why we sail. It is still more of an Art
than a Science!

Ole Thom

That sounds like an estimate based on an energy argument. However, I
don't think that case could be considered to be a closed system so such
energy balance need not apply.

Cheers

Jeff Morris wrote:

"Thom Stewart" wrote in message
...

Scott,

You've seem to have forgotten "The Gulf Stream Master" Jax. I'm sure he
can help you ride the eddies:^) Maybe even find you a stray current
heading south (g)


Jax also insisted that the time of high water and slack current must be the
same, to be otherwise would violate the laws of physics (on his planet).





Now, for what's it worth. The Tide Flow is a sine wave. Us common folk
understand that slack water is at the top and bottom of the wave. So
slack is, roughly about a hour and it is roughly in the upper 30%
counting the end of the rising tide and the beginning of the Ebb. 15% to
the HW and 15% roughly to the Max Flow. That means about two hours to
max flow, 8 hours of max flow and then another couple of hour of
diminishing flow to LW.


While the current flow in "simple harbors" may follow a sine curve, in cuts
between two bodies of water the flow is different. The curve is more
"squarish," that is, the flow ramps up quicker and stays high longer. The
duration of slack is reduced. The best example is Hell Gate in New York.

IIRC, the flow rate is proportional to the square root of the different of
height of the two bodies.

"Scott Vernon" wrote in message ...
I found some current charts for some areas, they give slack, max ebb,
and max flow. this I understand.
For other areas I find only the H & L tide chart. I want to make max
use of the tide (ebb). Say H is at 0800 and L is at 1400. is it simply
a matter of shoving off at 0800 and 'ride the out going tide till
1400?
TIA

Scotty


Perhaps if you modified your vessel and made it float like this one:
http://pao.cnmoc.navy.mil/pao/n_onli...hotos/flip.jpg

You would get a great current ride. This Navy ship has been in 80 foot seas!

Joe

That's one heck of a big submarine!!!


--
"j" ganz @@
www.sailnow.com

"Joe" wrote in message
om...
"Scott Vernon" wrote in message
...
I found some current charts for some areas, they give slack, max ebb,
and max flow. this I understand.
For other areas I find only the H & L tide chart. I want to make max
use of the tide (ebb). Say H is at 0800 and L is at 1400. is it simply
a matter of shoving off at 0800 and 'ride the out going tide till
1400?
TIA

Scotty


Perhaps if you modified your vessel and made it float like this one:
http://pao.cnmoc.navy.mil/pao/n_onli...hotos/flip.jpg

You would get a great current ride. This Navy ship has been in 80 foot
seas!

Joe

"Joe" wrote

Scotty


Perhaps if you modified your vessel and made it float like this one:

http://pao.cnmoc.navy.mil/pao/n_onli...photos/flip.jp
g

You would get a great current ride. This Navy ship has been in 80
foot seas!

What the heck is that? and where is it?

SV

"Scott Vernon" wrote in message ...
"Joe" wrote

Scotty


Perhaps if you modified your vessel and made it float like this one:

http://pao.cnmoc.navy.mil/pao/n_onli...photos/flip.jp
g

You would get a great current ride. This Navy ship has been in 80
foot seas!

What the heck is that? and where is it?

SV

It was buildt to research ocean currents.

Here is the story that went with the photo:

AG3 `flips' for research vessel duty with
Scripps Institute
by AG3 Michael DeMauro

It's not too often that one encounters a vessel with bulkheads and
decks designed for use in both the vertical and horizontal
position…including heads and showers!

Late on the afternoon of Jan. 15, I arrived at the Scripps Nimitz
Marine Facility in San Diego. Having never been to sea, I had no idea
what lay ahead as I made my way down the pier looking for the R/P FLIP
with TAD orders in hand. In the distance appeared the most bizarre
vessel I had ever seen. "This has got to be it," I thought.

FLIP, or Floating Instrument Platform, is a 355-foot long,
spoon-shaped buoy. Built in 1962, FLIP is owned by the U.S. Navy but
operated by the Scripps Institute of Oceanography, University of
California San Diego.

The FLIP has a series of ballast tanks along its submarine-like hull,
which can be strategically flooded with seawater. As the tanks fill,
the "top" end of the ship slowly lifts out of the water (i.e. Flips)
until the entire vessel becomes vertical, with 300 feet below the
waterline. The remaining 55 feet become a stable platform, ideal for
performing a variety of marine research experiments—so stable, in
fact, that although the vessel was designed to operate in 30-foot
seas, it has weathered 80 footers on more than one occasion.

The Office of Naval Research hoped for 20-foot seas for some of the
data collection periods during the planned underway. The bulk of the
research during this underway period focused on Air-Sea Interface
experiments, but in the past, FLIP was used in a variety of
experiments, ranging from communications to ambient noise to the
development of vertical arrays for acoustic sensors.

…and another step toward a mutually beneficial relationship between
the research and METOC communities was solidified.

On reporting aboard for the January trip, I became a bit disoriented,
to say the least. It's not too often that one encounters a vessel with
bulkheads and decks designed for use in both the vertical and
horizontal position…including heads and showers! Simply finding one of
the three berthing spaces entangled in the forward superstructure
proved difficult. Once settled in, however, I got straight to work
establishing communications with Naval Pacific Meteorology and
Oceanography Detachment Pt. Mugu, my home duty station.

The small crew and full agenda of the research platform didn't allow
me a free ride, and I was put to work straight away with various
tasks, including responsibility for taking salinity soundings on a
nightly watch from 2000 to 0300. During one three-day period I was
even pressed into duty as the ship's cook, with no apparent
casualties.

The Scripps research vessel began working with Pt. Mugu in September
1999 when AGAN James Ross embarked on a similar trip off the Southern
California coast. Tom Golfinos, FLIP OIC, has enthusiastically folded
Pt. Mugu sailors into the crew, making the trips interesting and
educational for the Sailors as well as the remainder of the crew.
Simultaneously, civilian and military forecasters at NPMOD Pt. Mugu
earned the trust of the crew by providing the vessel with tailored and
precise forecasts for the environmentally sensitive operations.

During the January underway period, a risky personnel and supply
transfer was planned for the middle of the trip, which involved
lowering a scientist down a rope ladder and dropping him into a rubber
dinghy over open ocean, a dangerous operation even under ideal
conditions. A go/no-go decision on executing the operation was based
entirely on the Pt. Mugu Forecast. CAPT (Ret) Bill Gaines, Assistant
Director Marine Physical Laboratory, Scripps Institute of
Oceanography, relied on the accurate sea height, wind, and visibility
forecasts provided by the detachment to eventually proceed with this
critical operation.

Although the weather didn't do its part by providing the FLIP with
prolonged periods of high winds and seas during the 17-day drift, a
good portion of the required data was collected, the personnel
transfer went without incident, and another step toward a mutually
beneficial relationship between the research and METOC communities was
solidified.

For a first-time underway period, my experience on the FLIP proved to
be a valuable learning experience and a rare opportunity to ride one
of the truly remarkable research platforms in existence.


Joe

Thanks for the link and the story. That is an unusual and interesting
vessel.

DSK

Joe wrote:
http://pao.cnmoc.navy.mil/pao/n_onli...hotos/flip.jpg


What the heck is that? and where is it?




It was buildt to research ocean currents.

Here is the story that went with the photo:

AG3 `flips' for research vessel duty with
Scripps Institute
by AG3 Michael DeMauro

It's not too often that one encounters a vessel with bulkheads and
decks designed for use in both the vertical and horizontal
position…including heads and showers!

(Joe) wrote in message . com...
"Scott Vernon" wrote in message ...
"Joe" wrote

Scotty


Perhaps if you modified your vessel and made it float like this one:

http://pao.cnmoc.navy.mil/pao/n_onli...photos/flip.jp
g

You would get a great current ride. This Navy ship has been in 80
foot seas!

What the heck is that? and where is it?

SV

PS. After reading this story I now know that the crew lied to me when
I saw this boat in 1972. They told me it was for researching ocean
currents.
In fact it was developing listening devices to track soviet
submarines.
What kind of sailors would lie to a 10 year old kid?

P.S. Notice the boat has a sail, it could be considered a sailboat
huh?

Joe





It was buildt to research ocean currents.

Here is the story that went with the photo:

AG3 `flips' for research vessel duty with
Scripps Institute
by AG3 Michael DeMauro

It's not too often that one encounters a vessel with bulkheads and
decks designed for use in both the vertical and horizontal
position?including heads and showers!

Late on the afternoon of Jan. 15, I arrived at the Scripps Nimitz
Marine Facility in San Diego. Having never been to sea, I had no idea
what lay ahead as I made my way down the pier looking for the R/P FLIP
with TAD orders in hand. In the distance appeared the most bizarre
vessel I had ever seen. "This has got to be it," I thought.

FLIP, or Floating Instrument Platform, is a 355-foot long,
spoon-shaped buoy. Built in 1962, FLIP is owned by the U.S. Navy but
operated by the Scripps Institute of Oceanography, University of
California San Diego.

The FLIP has a series of ballast tanks along its submarine-like hull,
which can be strategically flooded with seawater. As the tanks fill,
the "top" end of the ship slowly lifts out of the water (i.e. Flips)
until the entire vessel becomes vertical, with 300 feet below the
waterline. The remaining 55 feet become a stable platform, ideal for
performing a variety of marine research experiments?so stable, in
fact, that although the vessel was designed to operate in 30-foot
seas, it has weathered 80 footers on more than one occasion.

The Office of Naval Research hoped for 20-foot seas for some of the
data collection periods during the planned underway. The bulk of the
research during this underway period focused on Air-Sea Interface
experiments, but in the past, FLIP was used in a variety of
experiments, ranging from communications to ambient noise to the
development of vertical arrays for acoustic sensors.

?and another step toward a mutually beneficial relationship between
the research and METOC communities was solidified.

On reporting aboard for the January trip, I became a bit disoriented,
to say the least. It's not too often that one encounters a vessel with
bulkheads and decks designed for use in both the vertical and
horizontal position?including heads and showers! Simply finding one of
the three berthing spaces entangled in the forward superstructure
proved difficult. Once settled in, however, I got straight to work
establishing communications with Naval Pacific Meteorology and
Oceanography Detachment Pt. Mugu, my home duty station.

The small crew and full agenda of the research platform didn't allow
me a free ride, and I was put to work straight away with various
tasks, including responsibility for taking salinity soundings on a
nightly watch from 2000 to 0300. During one three-day period I was
even pressed into duty as the ship's cook, with no apparent
casualties.

The Scripps research vessel began working with Pt. Mugu in September
1999 when AGAN James Ross embarked on a similar trip off the Southern
California coast. Tom Golfinos, FLIP OIC, has enthusiastically folded
Pt. Mugu sailors into the crew, making the trips interesting and
educational for the Sailors as well as the remainder of the crew.
Simultaneously, civilian and military forecasters at NPMOD Pt. Mugu
earned the trust of the crew by providing the vessel with tailored and
precise forecasts for the environmentally sensitive operations.

During the January underway period, a risky personnel and supply
transfer was planned for the middle of the trip, which involved
lowering a scientist down a rope ladder and dropping him into a rubber
dinghy over open ocean, a dangerous operation even under ideal
conditions. A go/no-go decision on executing the operation was based
entirely on the Pt. Mugu Forecast. CAPT (Ret) Bill Gaines, Assistant
Director Marine Physical Laboratory, Scripps Institute of
Oceanography, relied on the accurate sea height, wind, and visibility
forecasts provided by the detachment to eventually proceed with this
critical operation.

Although the weather didn't do its part by providing the FLIP with
prolonged periods of high winds and seas during the 17-day drift, a
good portion of the required data was collected, the personnel
transfer went without incident, and another step toward a mutually
beneficial relationship between the research and METOC communities was
solidified.

For a first-time underway period, my experience on the FLIP proved to
be a valuable learning experience and a rare opportunity to ride one
of the truly remarkable research platforms in existence.


Joe