Seen the crews doing the mainsheet on the 49ers in Sydney?

Paul Brotherton explains why

Q: I sail a 29er with my sister crewing, and she has recently been bugging me to let her take the mainsheet - she has seen the 49er guys doing it at the Olympics on TV. Do I have to let her?!

A: The reason the crews take the mainsheet in the 49er class is to keep the boat flat, with no heel to windward or leeward. The 49ers typically sail in sheltered waters where the wind is shifty. If the skipper had the mainsheet, it would be impossible for them to release or pull in enough rope quickly enough to keep the boat flat and balanced. That’s because they only have one hand to control the sheet - we’re assuming that the other one is on the tiller!

If you can’t use enough mainsheet to keep the boat flat, and stop it from rolling to windward or staggering to leeward, then the helmsman would be forced to use the rudder to help keep the boat upright. That would definitely result in any high performance boat sailing less efficiently than if she was kept upright through trimming.

So the majority of 49er skippers take the jib sheet, and the crews take the mainsheet which is run directly from the underside of the boom. The benefit of this technique is that the crews will have both hands to rapidly adjust the sheet. The problems come with the timing of their trimming. The crews do not get the immediate feedback from the rudder that the skipper gets.

When you first start to use this technique, it’s frustrating for the helmsman that the sheet is not eased at the instant that the load comes on the rudder when a gust hits. Perhaps you should read an earlier question that I answered for some suggested trimming exercises, which will highlight how movement and trimming affect balance and ultimately performance.

The boat-handling will also need to change. Try running through a few tacks on dry land with your sister holding the mainsheet. It may also be that in a 29er it is easier for the skipper to take the mainsheet through the tack - as they have no trapeze wire to deal with - leaving the crew to concentrate on getting across and out on the new side smoothly and efficiently. Get a solid routine worked out, before adding the distractions of waves and real time sailing.

Ultimately, the whole process revolves around communication - which isn't easy at the best of times between brother and sister. So I challenge you to bite your tongue and help your sister to improve her skill - rather than just balling her out for not immediately being the ultimate skiff crew!