SailStats

The start

Set the start line by sailing to each end and pinging it, dropping the ends on a map, or typing coordinates. SailStats then gives you distance and time to the line, how early or late you will be at your current speed, and which end is favoured.

Setting up a start

Set the line

Sail to one end and tap Use Current Location, then the other. Or place both ends on a map, or enter coordinates directly.

Set the first mark, if you know it

This is what lets SailStats work out bias against the course as well as against the wind. Worth doing — they can disagree.

Set the countdown

Enter the start time, or run the countdown from now. It can be synced to the committee’s signals.

Pick the screen you read fastest

Three start views — a planning board, a numbers view and a line visualisation. Swipe between them.

Sail the last five minutes on time to burn

Positive means you are early and need to burn time. Negative means you are late and need to push.

What do the numbers mean?

NumberWhat it tells you
DTL — distance to lineHow far you are from the line, in metres. The one to watch in the last thirty seconds.
TTL — time to lineHow long it will take you to get there at your current speed.
TTB — time to burnThe difference between the countdown and TTL. Positive means early — you have time to burn. Negative means you are late and need to push.
BiasWhich end of the line is favoured, and by how much.

Which end of the line is favoured?

SailStats measures bias two ways, and it is worth understanding why both exist.

Against the wind is the classic calculation: the end that is further upwind is closer to the first beat, so it is favoured. This needs wind data.

Against the first mark asks a different question — which end starts you closer to where you actually have to go. On a course where the first leg is not a dead beat, these two answers can disagree, and the mark is usually the one that pays.

Does it tell me if I am over early?

Not as a verdict, and this is deliberate. GPS accuracy and the error in where you pinged the line ends are both larger than the margins that decide an OCS call, so an app that confidently said “you were over” would be lying about its own precision.

What you get instead is a potential OCS flag and the numbers behind it — your distance to the line at the gun and which way you were going — so you can judge it yourself, and so you can go back afterwards and see how close it actually was.

What are the three start screens?

They show the same data. Use whichever one you read fastest with thirty seconds to go, and swipe to it before the sequence starts rather than hunting mid-start.

Do I need instruments for any of this?

Not for the timer, the line, DTL, TTL or time to burn — those all work on your device’s GPS alone. Bias against the wind needs wind data; bias against the first mark does not.

Related

Get SailStats

Free on the App Store, and it works on your device’s GPS alone if your boat has no instruments.

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