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Dehler 36 Eye 2 Eye
Velocity Prediction Rating System

VPRS enables ballasted monohull yachts including sportsboats to race fairly against one another by applying Time Correction Coefficients (TCCs) to elapsed race times.

The TCCs are generated by a Velocity Prediction Program (VPP)—software that calculates a boat's potential performance in a range of wind conditions. A straightforward set of measurements for each boat configures the operation of the VPP.

Proved through testing and racing over 10 years, VPRS offers yacht clubs a single system which is easy to use—with the precision demanded by serious racers. Annual rating is just £25 for any boat.

Originally developed for PYRA in 2009, VPRS is used by all the major clubs in Poole Harbour as well as clubs in Chichester Harbour, the Solent, Weymouth, Plymouth and Ireland. We also have users in the Mediterranean and Brazil.

For some background information there is a Quick summary  or a  2 page overview

Stoneways Marine VPRS National Championship 2022

This year the Nationals take place during the Poole Regatta 2022 over the early May Bank Holiday, from 30th April to 2nd May.

Entries are open, so do get your entry in early, through the Poole Regatta web site.

It is shaping up to be a great event with two VPRS classes on two start lines, excellent race courses in Poole Bay and the legendary evening socials from Thursday through to Monday, culminating with the Nationals Prize Giving at Parkstone Yacht Club.

You're sure of some great VPRS racing so do get your entry in now.

Click here to find out how the Stoneways VPRS partnership began and more about the VPRS rating system.

VPRS Nationals 2022


Jan 2021
Happy New Year
The web site has now been updated for 2021, including transfer of all 2020 certificates into the archive pages. The annual revalidation email has been sent out to all current and recent users, explaining how to renew your certificate for the new season. Don't forget: this is a good time to ensure you have accurate measurement data on your certificate.
Mar 2020
New clubs
As ever we are very busy issuing certificates for the new season—but we are delighted to welcome both the Royal Southern Yacht Club on the Hamble and Lough Swilly Yacht Club in Ireland.
Jan 2020
Happy New Year
The web site has now been updated for 2020, including transfer of all 2019 certificates into the archive pages. All active VPRS users will soon receive an email regarding revalidation for the new season. Don't forget: this is a good time to ensure you have accurate measurement data on your certificate.
Mar 2019
Port of Plymouth
Following consultation with the sailing community in Plymouth we are very pleased to announce that the Royal Western Yacht Club, Plym Yacht Club and Torpoint Mosquito Sailing Club are all adopting VPRS for 2019. We look forward to hearing from boat owners regarding their rating.

Entry to the Plymouth Gin Spring Series includes the cost of a VPRS rating. The RWYC Pantaneus Triangle race will include a VPRS class and the Plymouth Regatta will feature the VPRS South West Open Championship.
Jan 2019
Weymouth Castle Cove
We are delighted to welcome Castle Cove Sailing Club to VPRS and look forward to receiving rating requests from individual skippers. Payments will be arranged by the Club. We are organising a couple of days for sail measuring in the near future - the Club will send notification of dates when finalised.
Jan 2019
New year, new season
Happy New Year to all VPRS users. The web site has been updated ready for the new season, with 2018 certificates moved into the archive pages and 2019 rating pages ready to go. The 2019 VPP is almost ready for release and the first applications have been received. Don't forget - if your boat is out of the water, why not take the opportunity to measure the keel and rudder, if it hasn't been done before...
Mar 2018
Poole Regatta and VPRS Nationals
The 2018 Poole Regatta will feature the Third VPRS National Championship, hosted by Poole Yacht Racing Association (PYRA). The Regatta is open to a range of classes including Fast 40+, HP30, IRC and VPRS. VPRS is offering event-only rating certificates free of charge for new entrants. You can read all about the 2017 Championship below.
Feb 2018
Royal Victoria Yacht Club
We are delighted to announce that the Royal Victoria Yacht Club at Fishbourne on the Isle of Wight will be using VPRS in 2018. We look forward to hearing from RVYC skippers in due course.
Jan 2018
No-spinnaker fleets
Following consultation with users we have changed the way we handle ratings for fleets where spinnaker and non-spinnaker boats race together. From now on, a boat's TCC will reflect its actual sail plan, which may or may not include a downwind headsail (for definition, see the measurement guide). Boats that are rated with a downwind headsail are also given a no-spinnaker TCC, for use only when sailing in a no-spinnaker class. The former "mixed fleet" rating will no longer be used. Race organisers should bear in mind that boats rated without a downwind headsail have an advantage on upwind legs and a disadvantage when off the wind.
Jan 2018
Happy New Year
All web site pages have now been updated for 2018, and 2017 certificates have been moved into the archive section on the rated yachts page. Application forms and the measurement guide have been updated to show standard UMS (Universal Measurement System) abbreviations to make it easier to share data with other rating systems including IRC and ORC.
Dec 2017
Merry Christmas
As 2017 draws to a close we can look back on a successful year for VPRS with nearly 250 active boats across fifteen clubs. As we get ready for the New Year, which includes the Poole Regatta and Third VPRS Nationals, we wish you all a Merry Christmas and fair winds for racing in the 2018 season.
Oct 2017
Welcome to SilaVetra
We are happy to welcome to VPRS five boats based in the Mediterranean, belonging to Russian company SilaVetra, with all best wishes for good racing.
May 2017
VPRS Nationals
In complete contrast to the the previous day, wind speeds averaged only 8 knots. In Class One the prizes sponsor Rob Gibson and his wife Kate ghosted away from the fleet for a comfortable victory. Deity, Fire Starter and Blue Jay were match racing for the Championship with the lead changing hands several times. Michael Braggs on Mikado came in second with Deity retaining the Championship with 3rd place only secured on the last beat.

1st Deity, 2nd FireStarter, 3rd Blue Jay overall.

Tactics were all in Class Two. Marris Otter deciding to go on a long starboard tack while the rest of the fleet tacked onto port. Mojito came 2nd and Exposition 3rd, but Marris Otter's tactic paid of with a comfortable 5 minute advantage that was maintained to the line, securing the Championship for Marris Otter.

1st Marris Otter, 2nd Exposition, 3rd Mojito.

Thanks to Cowes Corinthian Yacht Club for hosting the prize giving, to CCRC for Hosting and to Rob Gibson of Poole Sailing for supplying the prizes. And many congratulations to everyone who took part.

May 2017
VPRS Nationals
First day of the 2017 VPRS National Championship, hosted by the Chichester Cruiser Racing Club in the Eastern Solent.

With wind speeds averaging 28 knots, both races focused on those brave or foolish enough to fly spinnakers and asymmetric sails. Class One honours were shared between Keith Lovett on Fire Starter and Ivor Graham and Brian Thompson on Deity with Alan Bennett on Blue Jay between them in each race.

In Class Two, the first race saw Joe Cross on Exposition off to a flying start in his attempt to retain the Championship winning the first race with Mike Shrimpton and Rose Debenham on Marris Otter in 2nd and Ian Wall on Mojito in 3rd. Less than a minute separated them. The second, windier race saw the heavier Marris Otter take 1st place with Mojito 2nd and Exposition 3rd leaving all three in with a chance of the Championship the next day.

Feb 2017
First 2017 certificates
After the usual winter opportunity to make small adjustments to the VPP the first certificates for 2017 were issues on 26 February, nearly a week earlier than normal. If you're expecting to be rated but haven't heard from us, please make sure that you have both paid your annual fee and revalidated by confirming your measurement data.
Jan 2017
Preparations for 2017
2016 rating certificates have been moved to the archive page and new pages created to hold ratings for 2017. We will be emailing all active VPRS members shortly. Meanwhile, If you have your boat out of the water why not take the opportunity to check the measurements of underwater appendages?
May 2016
Poole Regatta and
VPRS Nationals
After three days of excellent racing we are delighted to report that, in VPRS class 1, first place was taken by Ivor Graham and Brian Thompson in Deity, second was Ed Wilton in Tom Tit and third was awarded to visitors Anthony & Alice Duggan in Phantom. In class 2, first was scooped by Joe Cross in Exposition; Kevin Cross took second in Selene and Simon Redhead came third in Rant n Rave. See the full results here. Well done to all who took part. The 2017 VPRS Nationals will take place in the Solent.
May 2016
Poole Regatta and
VPRS Nationals
We have no less than 29 boats - including three sportsboats - entered for the the first VPRS Nationals, taking place over two days of racing on 28-9 May 2016, as part of the Poole Regatta 2016. VPRS Nationals prize giving is Sunday evening at Poole Yacht Club. Good luck to all competitors.
May 2016
First VPRS Nationals
The inaugural VPRS Nationals take place over two days of racing on 28-9 May 2016, as part of the Poole Regatta 2016.
Apr 2016
Hayling Island SC
We are delighted to announce that Hayling Island Sailing Club has decided to adopt VPRS for the late Sundowner Series. HISC members - please get in touch to get your boat rated asap.
Mar 2016
First races of 2016
Poole Yacht Club holds its first races of the 2016 on 6 March, and we are pleased to welcome PYC classes 2 and 3 to VPRS. If you need a certificate and haven't got one yet, please get in touch as soon as possible.
Mar 2016
First 2016 certificates published
The first certificates for the 2016 have been published and are available now on the rated yachts page.
Jan 2016
Preparations for 2016 season
2015 rating certificates have been moved to the archive page and new pages created to hold ratings for 2016. If you have your boat out of the water why not take the opportunity to check the measurements of underwater appendages?
Dec 2015
2016 Poole Regatta
The 2016 Poole Regatta takes place from 28-30 May. Entrants will be able to compete under VPRS or IRC. We will be issuing limited-validity VPRS ratings (valid only for the Regatta) free of charge to visiting boats.
May 2015
Yachts & Yachting
Article published in Yachts & Yachting about PYRA and its efforts to get more people racing—in which VPRS plays an important role.
Mar 2015
Hardway Sailing Club
We are pleased to announce that following a presentation on 11 March, Hardway Sailing Club in Gosport is trying VPRS for the 2015 season. Hardway members: we will be working through your sailing committee to get your boats measured and rated in time for your first races.
Mar 2015
PYRA spring party
PYRA will be holding their usual spring recruitment party at 1900 on 15 March at Parkstone Yacht Club. All boat owners interested in joining PYRA are welcome. It's also a good moment to revalidate your VPRS rating.
Mar 2015
2015 Certificates
The first VPRS rating certificates for 2015 were published on 1st March. Don't forget: you must confirm your data AND pay for your certificate, either by joining PYRA, paying through CCRC or direct to us.
Feb 2015
As at 23 February a total of 41 boats have revalidated for 2015. With the first races scheduled to start in the next fortnight, please make sure you have both confirmed your boat measurement data with us and paid for your certificate (PYRA and CCRC both include the cost of a VPRS certificate in their membership).
Jan 2015
Invitations to revalidate your rating for 2015 were emailed to all active boats on 21 January. Please get in touch if you haven't received yours.
Jan 2015
VPRS 2015
We are busy updating the VPRS system ready for 2015. Invitations to revalidate for 2015 will be sent out in the next few weeks.
Jan 2015
CCRC adopts VPRS
Following a successful trial in 2014 we are pleased to announce that Chichester Cruiser Racing Club has adopted VPRS for its Alpha fleet. CCRC members: we will be in touch with individual skippers, where we have contact details. Otherwise we will continue to work through your Sailing Committee.
Mar 2014
CCRC trial
We are delighted to welcome the Chichester Cruiser Racing Club, which is trying VPRS in 2014. CCRC members: your Sailing Committee should be in touch regarding measurements for your boats. If you have any questions then please don't hesitate to contact us.
Mar 2014
2014 Revalidation
Revalidation forms for boats rated in 2013 were sent out on 23 February, and the first 2014 ratings were published on 1 March. If you are waiting for a certificate, make sure that you have replied to our revalidation email. If you were expecting a revalidation form but haven't received one, please let us know.
Mar 2014
Sail measuring
Sailmaker OneSails GBR at Hamble Point has been added to our list of approved sail measurers.
Feb 2014
2014 Revalidation
Pre-filled revalidation forms for boats which were rated last year will be sent out shortly.
Jan 2014
Sail measuring
Sail measuring at Poole Yacht Club, 29 January 2014: twelve more yachts have authenticated sail measurements. If you would like to have your sails measured for 2014, please get in touch.
Jan 2013
2013 Revalidation
Pre-filled revalidation forms for boats rated last year have been mailed out. If you were expecting one but haven't received it then please let us know.
Dec 2012
2013 Application forms
Measurement guide
Application forms for new ratings, and the 2013 measurement guide, are now available for download. There is only one change this year: sail construction will be captured separately for mainsails and headsails. Guidance on making the correct declarations is given on the measurements page.
Revalidation forms for boats with 2012 certificates will be sent out in January.
Nov 2012
Parkstone Yacht Club
Classes 2 & 3 adopt
At the recent cruiser class AGM, Parkstone Yacht Club classes 2 and 3 voted for adoption.  All cruiser classes now use VPRS for Monday evening racing, which should simplify the scoring and make the class divisions easier to manage.
Sept 2012
Sussex Yacht Club
to trial VPRS
Sussex Yacht Club, which currently rates with a mix of IRC and PY boats, has decided to trial VPRS in 2013. The system will be used to score race results and award prizes across the whole fleet, and if successful, will be adopted from 2014.
May 2012
Poole Class 1
moves to VPRS
Poole Class 1, which attracts the bigger boats, has now followed Class 1A and will use VPRS. Class 1A adopted VPRS last year and has seen considerable growth since then. The switch will allow the larger fleet to be divided into a more equitable set of racing classes.
March 2012
Stability requirements
for yacht racing
Guidance on stability requirements for yacht racing and manufacturing is drawn from a number of sources, with various different measures used to judge compliance. This can be rather confusing, so a summary page (Stability tab above) explains some of the compliance options for yacht racing.
Jan 2012
Revalidation underway
Measurement guide revised

System updated
Revalidation forms are being sent out now. There are some changes - the details are on the measurements page. Certificates for the new season will be issued from the end of February.
The measurement guide has been revised - and there is a new upwind-headsail measurement. A set of keel drawings, split into planforms and sections, will give a better idea of surface area and volume distribution. Keel construction materials are listed, and lifting/swing keels and associated hull ballast can be identified.
The system software has been amended in line with the above changes as well as the feedback from 2011. Final testing will take place over the next few weeks.
October 2011
Rating review
VPRS summaries
1 + 2 page
With the 2011 racing season coming to a close, there is plenty of opportunity to gather feedback and to decide on improvements to feed into the VPP models for 2012.  In addition, there will be some minor changes to the measurements and a set of keel diagrams will improve differentiation between keel types.
In response to widening interest and some direct requests, a couple of short system summaries are now available - links above.
May 2011
Poole Yacht Club
2nd weighing session
A second weighing session took place on Friday 13 May at Poole Yacht Club, again in good weather. An easy half day with only 5 boats to weigh, but well worthwhile, with one recording a gain of 586 kg and another of 14%.
April 2011
Poole Yacht Club
weighing session
A weighing session was conducted on Friday 15 April at Poole Yacht Club - in almost perfect conditions. Most of the boats were very well prepared and there were plenty of people freely giving their time to help out. As a result the day was a great success - and with 18 boats weighed - the cost was very reasonable.
March 2011
PYRA recruitment
party at Parkstone

RMYC Class 2
racing with VPRS

VPRS upgrade complete
Ratings now available
PYRA recruitment is underway - if you signed up at the party held at Parkstone Yacht Club then please remember to return your application form well before the first race. The VPRS joining fee has been waived for PYRA members in 2011; full membership includes entry into the system as well as the rating certificate.
The Class 2 boats at the Royal Motor Yacht Club (at Sandbanks, near Poole Harbour entrance) will now use VPRS to score their racing - which takes place on Thursday evenings.
VPRS has been revised and tested - and the system parameters have been frozen for the new season. Most of the changes relate to sail design, construction and reefing, but moveable ballast is also now accounted for.
February 2011
Poole Class 1A
to use VPRS


Website upgraded

Parkstone Cruisers AGM
Class 1 adopts VPRS
Class 3 to decide
Poole Class 1A - which races on Tuesday evenings and at the weekend - has decided to use VPRS to score their series. A weighing session, for which a lot of interest has been expressed, is being organised for mid April. This will provide a great opportunity to take a number of additional measurements - and ensure that we have a fair set of ratings early in the season.
The website is now ready for the 2011 racing season. The measurement guide is more detailed and there are some additional accompanying diagrams.
For new rating applications, PDF and Excel forms are available for download.
A presentation explaining the design and use of the system was given to the Parkstone Cruiser Class at their AGM on 9 February. This was followed by a lively discussion, after which Class 1 voted convincingly to adopt VPRS. As expected, the situation was less clear for classes 2 and 3 which decided to stay with PHHS. However, the debate continued after the meeting and there is now a possibility that class 3 will also adopt.
January 2011
VPRS upgrade started
VPRS is being upgraded to recognise the advantages of 'deck sweeper' head - sails and laminated sail construction. The way in which weights are captured will be rationalised - and moveable ballast will be accounted for. Finally, the system will be extensively re-tested, with an emphasis on identifying sensitivities to small errors in the measurement data. Enhancements planned for later in the year will see the prototype VB/Excel platform replaced by something more powerful and maintainable - and there will be some functional additions to the web interface.
December 2010
Poole Class 1A
A presentation was given to Class 1A members at Poole Yacht club to explain the design of VPRS - and the benefits of using it when compared with the other local systems. An interesting discussion followed during which many useful points were raised; some of these will be addressed in the system upgrade this winter.
November 2010
PYRA adopts VPRS
across all classes
Finally, after a year of evaluation, and a lively debate at the AGM, PYRA voted to adopt VPRS across all classes - replacing both IRC and PHHS. This had the immediate beneficial effect of simplifying the class structure, with the promise of much more competitive racing in 2011. As a consequence of this decision, there has been greater interest from the individual clubs in Poole harbour.
September 2010
Weymouth yacht clubs
express interest
There has been some interest and favourable exchange with the clubs in Weymouth, although we have yet to show the system in any detail.
April 2010
VPRS prototype
goes on trial
Having evolved from a personal research project that started more than 3 years ago, into a sophisticated VPP-based yacht rating system, VPRS was finally ready - after months of work over the cold winter months, for the 2010 trial.
October 2009
Presentation to
PYRA Committee
In response to concerns about PHHS, Ruth Kelly gave a presentation to the PYRA Committee on rating and handicap systems and introduced the prototype VPRS system as one of the possible alternatives. The committee decided to sponsor further development of the system and to run a trial during the 2010 season.

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