Portsmouth Yardstick

UTLSC PNs 2023

UTLSC PNs 2023 are based on the RYA Portsmouth Yardstick data for 2023 and the data provided by the RYA based on UTLSC results 2015-2021. See below for details

ClassUTLSC 2023 PNRYA National 2023 PN
used for the Commodore’s Cup

Cherub (Veteran)11401140
Hartley 12.2*11881188
Laser 4.711861210
Laser Radial11111150
RS 20010471046
Streaker Wave*12171217

* RYA did not provide NATIONAL PNs for these classes as they have insufficient data.

RYA Trend data provided by email to Penny Abbott on 3rd March 2020 used for
Bosun, Gull, Otter, Hartley 12.2 & Streaker Wave

Cherub (Veteran) PN taken from Class website

Click here to download this list

Portsmouth Yardstick

Some classes are faster than others. E.g. A Laser is faster than a Topper.
To enable boats from different classes to compete against each other in the same race classes are given a Portsmouth Yardstick Number (PN).
These PNs are used to calculate a corrected time from the elapsed time. The person with the lowest corrected time is the winner and so on.

Corrected Time = Elapsed Time * 1000/ PN for that class

How are UTLSC PNs set?

For several years the RYA has been providing National PNs for many classes based on data from many sailing clubs.

UTLSC has been uploading results to the RYA since 2013. The RYA provides an analysis tool that gives a Suggested PN for each class based on UTLSC data alone. At the same time the RYA recognises that if there is insufficient data provided the Suggested PN is not statistically sound, so they also provide a Confidence Limit for each class based on the volume and stability of the data.

The UTLSC PNs are calculated by by moving from the National PNs towards the Suggested PN according to the Confidence Limit.

UTLSC PN = National PN + ((Suggested PN – National PN) * Confidence Limit)

E.g. For the LASER

National PN: 1099
Suggested PN: 1070
Confidence Limit: 77%

UTLSC PN: 1077 = 1099 + ((1070-1099)*77%)

From 2019 – 2021 the Commodore’s Cup used Personal PNs – These were calculated using results from previous series – click here for details

If you have any queries please ask Penny