spinlock irc logo words sRE: JPK 10.80 and JPK 10.10 Length of Hull (LH) Measurement
BY: James Dadd & Jean Sans
DATE: 22nd June 2016

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Following check measurements made during the past few weeks it has become apparent that the current standard hull data for the JPK 10.80 was potentially incorrect. As such both the RORC Rating Office and UNCL Centre de Calcul have worked together, along with the builder JPK to carry out further measurements on both existing JPK 10.80s and currently in-build JPK 10.80 yachts.


From these measurements we have confirmed that the original data was incorrect with regards to Length of Hull (LH). We have also checked other primary dimensions and have found no other errors. It appears that the error originates from the initial survey for compliance with ISO requirements. The original value was 10.80m and the correct value is 10.84m.

As a result of this we have also carried out some check measurements on the JPK 10.10 and found that a similar mistake has occurred. In this case it also appears that the only error is with regards to the LH and the correct value is 10.04m rather than the original 9.99m. The previous value again originates from the survey for the ISO requirements and the current ORC data files.

Following discussions with JPK Composites it is apparent that this is a simple error and there is no suggestion of any foul play. JPK Yachts have been completely open and provided us with all available assistance in getting to the bottom of this matter.

It has been agreed that all JPK 10.80 and JPK 10.10 yachts currently rated will have amended certificates issued with immediate and no retroactive effect reflecting this new standard data. Those modified certificates will not be taken into account for a current event. We will also inform the ORC of the error in their data files.

It is always our priority to ensure that all competitors are racing with fair and accurate data, and is of paramount importance that we are completely open with all competitors about any such errors, how we are dealing with them, and how we can learn from them for the future. As such we are reviewing the processes by which we validate standard hull data for the future to try and ensure that such mistakes do not happen in future.

Jean Sans
UNCL Centre de Calcul
James Dadd
RORC Rating Office