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Racing in General



You vs. "Them"

Comparing boats on the fly

How well are you doing compared to your competition?

PHRF handicaps are pretty straightforward in time-on-distance scoring – if your boat has a rating 10 points lower than another boat, you give them 10 seconds per mile.

Time-on-time scoring is less intuitive than time-on-distance. A boat's rating gets converted to a (non-linear) correction factor. Each boat's actual finish time is then multiplied by its correction factor, and the corrected times are compared to determine finish places. By this point, the relationship between handicap ratings and finish places has become pretty convoluted. (See how to score for an explanation of the formal scoring calculations.)

Seconds per hour

An easy way to handle time-on-time is to convert the handicap rating into a seconds-per-hour difference between two boats. You can then estimate the correction easily based on the time sailed. (That's assuming you accurately time your race, as of course you should.)

The process is a little more complicated for a fleet, because you have to calculate the seconds-per-hour difference for each PHRF rating in the fleet, a laborious process at best. But I've saved you that drudge work. The better approach is to create a custom table for your own boat. It's easier than you think.

Using your custom table

How well did you do against "them"?

Look up the correction between your boat and their boat in the table.

  • Find your finish time in minutes in the left column
  • Find the column for their boat
  • The intersection is the "break-even" difference (in seconds) between the two boats, given your finish time
  • If they sail longer, you beat them

Did you beat them?

For example, you sail the Hestir 30 (rated 102), your competition is the S2 7.9 (rated 171). You finish in 50 minutes:

  • 50 minutes in your table yields 317 seconds (5:17) for the S2 7.9
  • Add that difference to the time you sailed: 50:00 + 5:17 = 55:17
  • That 55:17 is their "break-even" time
  • If they sail longer, you beat them
  • Alas, that extra 5:17 is a long time…

Another way to look at it, after you finish they still have 5:17 in which they can still beat you, and you just can't do a thing about it!


Updated 29 January 2013

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