The Portsmouth Number list - a split from the norm

by Emma Slater, RYA 28 Feb 2013 13:08 GMT 1 March 2013

The RYA Technical Department is set to issue the latest Portsmouth Number list © Paul Wyeth / RYA

With another year's worth of online data added to the analysis, the RYA Technical Department is set to issue the latest Portsmouth Number list (PN).

Whilst some of the changes to be published will play very much into the anecdotal after sailing bar discussions, others will leave some scratching their heads as to what the RYA are up to. So in order to put some of the changes into perspective, it's worth looking at where and how the numbers are born.

The data collected and collated by the RYA from its clubs is amalgamated into a document known as the "Digest". The Digest contains the recommended performance numbers for all of the classes submitted by each club as they are seen as appropriate by that club. When looking at how a club assess the relative performance of each of its classes, you need to take into account the vast variety of factors that will affect its perceived performances.

Andy Wibroe, RYA Technical Co-ordinator, explains further: "The data that we get may not necessarily be the championship winning boat or reflect the absolute speed performance of the boat but will be an accumulated average.

"If a boat is consistently used as a youth training boat within club sailing then it will never really be sailed to a high consistent level. On the other hand a class which is more actively sailed in open meetings, where sailors get to test their skills more keenly the average club boat may be sailed to a higher level than average."

This will result in certain classes having a higher than average performance factor and others a lower average, meaning that classes will continually over achieve against the RYA published number and others under.

The method of collecting the data from the clubs has meant that the Portsmouth Number list published this year is closer to the National Average performance factor of each of the classes, but it's important to note that this will need to be tweaked and adjusted for each clubs racing to allow for their own local adjustment factors. On its own, the PN list will give an excellent starting point for club racing but will need to be tweaked locally for club racing.

One thing missing from this year's number list will be the cruiser numbers. The RYA have not received enough data from clubs to be able to publish a PN list for this area of racing and instead have been working on replacement scheme built on slightly different foundations.

The National Handicapping for Cruisers or NHC, has been built up and developed over the past three months with welcome assistance from a variety of partners.

NHC moves away from the traditional process of collecting club data but instead works on a formula and measurement system to build up a base list. This base list will contain over 1200 different boat types when published next weekend.

Bas Edmonds, Technical Manager, comments: "The idea behind NHC is not to create a measurement scheme where owners are measuring their own yachts to gain an advantage. It is based around a performance handicapping element where small variations in the boats measurements are effectively smoothed out by looking at how the boat actually performs around the race track with its crew on board.

"The difference of having a folding propeller in the past has been treated as a set percentage, however under NHC this is not assumed as a certain performance factor instead looking to see how the boat sails.

"Performance handicapping is very successful in developing the sport of golf and we feel it has a strong position in helping the sport of sailing continually develop its sailors through their learning experiences in racing."

An important part of NHC is the adjustment process and the RYA is grateful to be working with Sailwave and HAL who have developed their programs alongside the RYA and will be releasing new versions of their programs at the same time as the RYA release the base list.

"With the increasingly strong data we are getting for the Dinghies from PY Online and the change of scheme for the cruisers, I am confident that the RYA is starting to offer some strong options for clubs in helping develop their racing for their members and to continue motivation within our sport", concluded Bas.

The Portsmouth Number list and the NHC base list will be published on the RYA website on Friday 01 March.