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How
can I get polars for my boat?
Does
SailFast consider the sea state in its routing?
What
are GRIB files?
Can
I use SailFast on more than one computer?
What
is the procedure for activating SailFast after it is installed?
Do
the sailing rules permit me to access weather data during a race
and use it with SailFast?
How does SailFast compare to other routing programs?
How
can I get polars for my boat?
Polars may be available from the designer of your boat or from US Sailing.
If a sister ship of your boat has received an IMS rating, then polars will
be readily available from US Sailing. We suggest you call US Sailing’s
Offshore office to get the details. You should find that there are two products
available, a full-blown performance package including graphical polar diagrams,
or a lower-cost LPP/VPP print out without graphs and other useful explanations.
If your goal is to save money the print out should provide the numerical
data that SailFast needs, but double check with the Offshore Office. www.ussailing.org
, 1-800-USSAIL1 or 401-683-0840.
For
a fee, SailFast can also obtain polars for you, preloaded into the program.
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Does SailFast consider the
sea state in its routing?
No. SailFast does not try to evaluate how the sea state affects boat speed and
the predicted elapsed time. BACK TO TOP
What are GRIB files?
GRIB files contain detailed weather forecast data such as wind speed
and direction, atmospheric pressure and sea surface temperature. The
data is typically specified on a regular lat lon grid of points, and
normally a single GRIB file will include multiple sets of forecasts
over a period of days. An example would be a forecast for every 3 hours
for the next 72 hours. GRIBs contain highly compressed binary data to
minimize file size. A special reader is required to view the data and
there are a number of these available, both commercially and free.
SailFast
will read GRIBs directly and uses the wind and current data to predict
boat performance over possible tracks. It is straight forward to download
a GRIB file from the internet before an offshore race that gives forecasts
for the week. If you have the ability to access email from your boat
via cell phone, sat phone or SSB radio; then you can get updated forecasts
during the race. Of course with a cell phone one is limited to fairly
close to shore distances.
Using only GRIB forecasts for optimal routing
doesn’t permit the navigator to consider other wind variations that may
well occur, so SailFast also permits the user to modify forecasts and
perform What-If routing scenarios.
(SailFast 2005 did not support the
use of GRIB files.)
Last updated: May 2008
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Can
I use SailFast on more than one computer?
The SailFast license allows you to install and use the program on
2 computers. The intent is to let you use the program at home on a desktop
PC and to also be able to run the program on a laptop on board. Software
piracy is prevented by using an activation method
similar to how Windows XP is installed.
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What
is the procedure for activating SailFast after it is installed?
After you install SailFast on a PC, simply start the program. The
program will display a Computer Code to be used to register the
product on this web site. For registration you will also need your
program serial number, which is the 16 digit Receipt ID you receive
when you purchase. After you register an activation code will be
emailed to you that you will
use to enable
SailFast
to run
on
your PC.
The program will only run on the PC you first install it on. Sending
the activation code is not automated so allow up to 24 hours to receive
it.
To install on a second PC you will need to repeat the procedure and obtain
another activation code.
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Do the sailing rules permit me to
access weather data during a race and use it with SailFast?
Yes, unless the Notice of Race (NOR) specifically prohibits this. The MHOR
2007 race committee has looked at SailFast and deemed it to be legal.
However there are some limitations to follow to be legal, so please read
on.
First, using a navigation program falls under the broad category of
equipment covered by the Racing Rules of Sailing (RRS) rule 3 (J) which
states "The
use of electronic aids to navigation and safety at sea is permitted."
The
second and perhaps more important consideration is rule 41 OUTSIDE HELP
which applies during a race and says "A boat shall not receive
help from any outside source, except …" , and the exception
41 (D) which states "help in the form of information freely available
to all boats;"
So receiving and using GRIB files and other weather information
that is FREE and accessible to anyone is permitted. Getting GRIB files
from a service
that charges for them would not be legal under the rules.
The Americas
Cup Jury interpreted this in AMERICA’S CUP 32, AMERICA’S
CUP JURY
JURY NOTICE JN050 which can be accessed by clicking the link below:
http://jury.americascup.com/multimedia/docs/2006/09/decision_[05.09.06].pdf
Decision
[31] RRS 41 states, in part:
"A boat shall not receive help from any outside source, except. . .
(d) help in the form of information freely available to all boats;"
The Jury considers that the term “outside source” means a source
outside the boat.
As noted in paragraph 3.5 of Alinghi’s submission of 18th July, RRS
41 as it now stands is significantly different from the previous edition
of the Racing Rules of Sailing 2001-2004, when RRS 41 did not have the
exception contained in the current RRS 41(d) being the 2005-2008 edition.
[32] The question of what information is "freely available" was
interpreted in Royal Yachting Association case number 5, 2005. That case
provided:
QUESTION
Is weather information sent to a mobile phone, to a receiver or to a computer
by a weather bureau as part of a dedicated subscription service ‘freely
available’ for the purposes of rule 41(d)? Is the cost of that service
relevant? Is information available to all on the internet ‘freely
available’, given that a subscription has to be paid to an internet
service provider?
ANSWER
Once a subscription has been paid to a generally available and non-specialised
communications service, such as an Internet Service Provider, a telephone
service (mobile or terrestrial) or a television licence, any information
that is then available to the general public, or is available to all competitors
in the event, can be accessed readily and at no further cost (other than
the cost, if applicable, of a standard rate call or connection) is ‘freely
available’. The notice of race and sailing instructions may change
rule 41 to widen or narrow this.
The Jury agrees with this interpretation.
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How does SailFast compare to other routing programs?
If you have investigated other software packages you know that there
are
various products available that will do optimized routing. In general
all
the top end programs employ polars and compute isochrones to find the
fastest route. Some programs were initially developed as racing innovations
with America's Cup contenders while others added routing as an optional
feature to navigation and charting suites. When you look at pricing you
should find that SailFast is only 20-50% the cost of alternatives. If
your need is optimized routing for offshore racing and you don't need
the
other bells and whistles, SailFast is a great choice.
Lastly, SailFast includes detailed current predictions for the Gulf of Maine.
Some competitive products do not.
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