IRC specialist and Olympic helmsman Mark Mansfield analyses the rating rule changes agreed for next season.

Following the IRC Congress earlier this month, chaired by Ireland's Michael Boyd, changes were agreed for the 2021 season. The two main areas of change deal with Spinnaker Pole/Sprit lengths and Flying Jibs. 

Bowsprit/Spinnaker Pole IRC changes for 2021

Whisker poles

In late 2019 IRC came up with a new method of dealing with Whisker poles which were becoming more common, especially on larger Offshore boats, where the offwind sails like Code 0s and Flying Jibs could be sheeted further outboard on the whisker pole outriggers.

Some confusion arose around the 2020 revalidation form and options that were offered to owners who did not have a whisker pole but did have both a sprit and also used a spinnaker pole for Symmetrical Spinnakers. It appears some of these boats may have been over-penalised in 2020.

For 2021, a new definition of what is a whisker pole has been agreed by World Sailing and an individual question will now be asked in the 2021 revalidation to determine if a boat is carrying one.

It means the options for owners who have both a bowsprit and also use a spinnaker pole become simpler.

Pole/Sprit sizing

Up to now, it appears that your STL (from front of the mast to end of Sprit or end of pole) was the only figure that was taken to cover both your pole length and how far your Sprit extended. So if you added a sprit to your bow and this came out further than your pole, then it cost nothing in rating to extend your pole to that same length. However, many owners did not go to the bother or expense of splitting their pole and extending it. 

For 2021, it now appears that if your pole is not as long as your Sprit, you may, in some circumstances, get a better rating for having the shorter pole. Both the sprit length (STL) and the pole length (SPL) can and should now be provided in your 2021 revalidation. This may also mean that owners adding a sprit might opt for a longer sprit compared to the very stubby Sprit we have seen recently, and not incur the same penal penalty. Trial certs should be looked at to confirm this.

The text from the IRC rating office is below:

To fully benefit from the changes owners are asked to confirm the pole configuration of their boat, and SPL as well as STL if applicable when applying for a certificate. For revalidation, SPL should be supplied if it is different from the previous rated STL. If SPL is not supplied then STL will automatically be used for spinnaker pole length if applicable, which may result in a higher TCC. Boats may see a change in their TCC for 2021 and the rating effect will depend on the specific configuration of the boat.

Flying Jibs—IRC Changes

The way IRC handles Flying Jibs is changing as is their definition.

History—Flying Jibs

Flying Jibs became popular due to a change in the IRC rules back in 2017 when it became legal for a headsail to be tacked forward of the forestay onto a sprit. This allowed a Headsail to be designed with a high clew which was the same size as the boats Jib, and so no extra rating penalty as only the largest is rated. These Flying Jibs could then be used with another jib or staysail inside them. Effectively it was a small flat code 0, normally on a furler, which was very efficient when power reaching in more wind than a code 0 could take. Code 0's were rated as spinnakers and so had to be designed wide in the middle to meet the 75% mid girth IRC requirement. However, the flying jib had no such restriction and could be designed to be quite flat.

Not too many of these sails have turned up in Ireland so far, but internationally you could see them become popular especially on larger offshore boats that often set 2 or 3 headsails forward of the mast.

A Flying Jib used with headsail. This will still be allowed in 2021 but the Flying jib like this will continue as a headsail

Changes for 2021—Flying Jibs

The new 2021 rule now has come up with a new definition of what exactly is a flying jib and requires any boat carrying one or more of these to report them on their 2021 revalidation and they will be included in their new Cert, and a likely penalty will be incurred.
A headsail design that is the same size or smaller than a boats max size headsail can still be set on a boats sprit, so what was referred to as a flying jib over the last few years continues, per IRC, now defined as a headsail. These sails do not need to be reported as a Flying jib.

Effectively the new Flying jibs are a flat, perhaps slightly smaller Code 0. From the graph below, you will see that they can be quite costly on rating so a prolonged period of use in their perfect conditions would be needed to justify this rating increase.

Owners declaring a Flying Headsail within the IRC definition will see a change in rating for 2021. Some representative examples are shown above these are for guidance only as the rating effect will depend upon the rig configuration and many other boat factors. Source IRC

The J/99 Juggerknot at the start of Fastnet 450 race on Dublin Bay with flying jib and headsail set Photo: Afloat

The definition of what is a Flying Jib is twofold.

1. It must have a mid-girth of at least 62.5% of its foot. This will force sail designers to design these sails much fuller than they would normally want to do. This is to stop these sails effectively been used upwind as large jibs.
2. IRC has put a minimum foot length of these sails to stop very small Flying Jibs being designed. There is a formula for this.

The full details and formulas can be found here

The Rating Office has provided the above graph of what penalties will likely be incurred by boats that use certain sized Flying jibs going forward. These are based on sail sizes that might be efficient to design. It is unlikely that the penalty will prove attractive to take for IRC boats that do not do long offshore races. 

Other IRC changes

There have been some other clarifications mainly around wording, age dates, series dates and the use of foils. These are all covered in the IRC changes link given above.