FAQ.
Frequently Asked Questions
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?
Can I use SailFast on a Mac?
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 and current 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.
Ocean surface
current is not available from the common atmospheric weather models, so
obtaining current Gribs is more of a challenge. NOAA does produce current Gribs
of the North Atlantic as part with their
RTOFS (Real-Time Ocean Forecast
System) model which is updated daily. Unlike some other routing programs
which require a single customized Grib, SailFast will operate correctly with
multiple Grib files (ex. one for wind, one for current) .
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.
Last updated: Jan 2009
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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/en/jury_documents/index.php?idPage=2&idIndex=304
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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Can I use SailFast on a Mac?
SailFast has been
written to run on various Windows operating systems. A native Mac version is not
available. However customers have been successfull using SailFast on a Mac using
a Windows emulation program. In one reported case Parallels Desktop Version 5
was used on a MacBook Pro. If you try running on a Mac please install the Demo
version first to verify that it will work for you. In the example cited above
the install required a few extra Windows files be installed manually, so contact
us if you have problems.
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