Next years Tasaki Osaka Cup, the Melbourne to Osaka double handed yacht race, will allow the entry of water ballasted boats for the first time.
The acceptance of water ballasted yachts should provide for some exhilarating sailing and an opportunity to smash the existing Race record of 26 days.
The Tasaki Osaka Cup has received 20 entries to date (from Australia, Japan, New Zealand, Denmark & France) and the Race Committee would encourage the support of further entries to this unique and challenging non stop ocean race that spans 5,500 nautical miles, the longest longitudinal race in the world.
So far, several Tasaki Osaka Cup entries are considering using water ballast including the late Peter Blake's Kontrol. The extent to which a boats performance will be improved is an unknown factor at this stage as most boats have yet to sail in a water ballasted configuration. However the results are likely to be spectacular given the performance of boats in normal trim. Based on the Volvo 60 and Open 60 experience where daily runs went from around 15 knot average to just over 20 knots average for the 24 hours with the advent of water ballast, we could see a similar increase in performance in the Osaka boats.
The innovation of water ballast has been used for a few years now in the Volvo 60 and Open 50/60 long distance ocean racing classes and, with the spectacular increases in performance which water ballast allows, has become the standard for that type of racing.
Most sailors will know of the stunning performance of the Volvo 60 Nokia in the 1999 Sydney where she smashed the record, not to mention the spectacular television footage of the Volvo Race fleet coming up through Bass Strait prior to the start of last years Hobart at speeds of 30 knots plus. This level of performance is something most ocean racers only dreamed about in the past.
The management of water ballast has come a long way since it was first tried out in the 80's with sometimes disastrous results.
In the Volvo 60 class, the arrangements are highly developed and yet amazingly simple and safe. In these boats there are six tanks outboard of the accommodation space, arranged so that the boat can be trimmed fore and aft as well as athwartships. Volvo 60s carry 3 tonnes of water ballast per side, the equivalent of 40 crew permanently on the rail.
Water is pumped into the tanks by a single pump centrally located in the bilge forward of the companionway. The pump discharges into a manifold with a series of valves to control which tank is filled. This pump has the capacity to fill each of the tanks in about 26 seconds. However, when the boat is ballasted, precious power can be saved by transferring the water by gravity to the other side immediately before the boat tacks or gybes. This process takes around one minute per tank.
However, as you might imagine, it is not desirable to have all the ballast on the wrong side for too long as the boats are very slow lying on their ear. It is therefore common practice to dump ballast to 50% and then tack with the remaining 50% being then topped-up with the pump. In an emergency, the entire contents of the ballast tanks can be pumped to windward or overboard in less than a minute to restore normal stability.
According to Peter (Spikey) Doreian who was a helmsman in the most recent Volvo race, water ballast has two other advantages. Spikey points out that you dont have to feed the additional 40 blokes and you can put them all overboard in light weather when the extra weight is a disadvantage.