Maiden Hong Kong continued

In part two of this article we look at the radical hull and rig design of Frank Pong's new super-maxi

This article follows part 1 published yesterday

The hull of Maiden Hong Kong is narrow with a waterline maximum beam of 3.8m. However the hull has wings at deck level similar to KZ1 or the Italian Open 60 Shining, extending the overall beam to 8m. In the wings there is tankage each side for 5 tonnes of movable water ballast. Unlike Mari Cha IV which has water ballast and canting keel systems that are used at different times, the former for example to add weight to the boat when powering upwind in breeze, on Maiden Hong Kong the water ballast is used in the first instance simply to provide additional movable ballast to the canting keel.

In terms of their use designer Juan Kouyoumdjian sees the keel first being canted in 6 knots of breeze and fully canted in 8 knots. Above 12-14 knots of wind speed the water ballast is brought on board. He does not envisage a time water ballast is used without the keel being canted fully.

Cleverly the tanks are fitted with pressure valves so that in the event of a massive deceleration the water can escape between the tanks and ultimately out of the forward compartment. "That’s important so that the boat will not rip itself apart. If you don’t have those things you end up overstructuring the boat 99% of the time," warns the designer.

The second role of the water ballast is to alter the fore and aft trim of the boat. This is not just to help raise the transom out in light weather or raise the bow when sailing into large waves. With the keel canted side force is created by the forward foil and the rudder, but Kouyoumdjian says that there may be occasion when more is needed and in this case the boat can be trimmed forward or aft and this used to harness lift from the keel foil, despite it being canted, by altering its angle of attack.

An issue with having a narrow hull is that its ability to plane is reduced. Kouyoumdjian says that if he had to do a Maiden Hong Kong mk2, it might be a wider lighter boat but with that would come a whole host of other problems related to foil cavitation. The present boat is expected to have a speed wall in ideal flat water conditions of 33-35 knots. "Oceanic races are not won in heavy airs, they are won in the light," he argues. "I like to think of oceanic boats as being ones that are very fast when it is light and can keep the pace when it is heavy. I think weight is very important then and anything over 30 knots I don’t think this boat will have any sails up and it will still be doing 20 knots."

To the observer there would appear to be a significant problem with the wings trawling in the water or being hit by waves. Kouyoumdjian says the wings are will not touch the water until the boat heels by more than 35 degrees and even then it will not be a major issue. "The drag and the influence of the yaw that the wings have when they hit the water is accounted for in the balance of the boat. I think they will hit the water the boat and the boat will slow down but to be more honest I am more concerned about the windage of the windward one rather than the leeward one hitting the water."

The hull is obviously built in carbon fibre, but structurally in addition to transverse bulkheads there is a substantial longitudinal bulkhead simply because the boat is so slender it has the potential to banana due to fore and aft rig loads. The interior is fully 'race boat' with carbon fibre furniture, pipecots and few mod cons. The sleeping area is aft where there is also a shower, while mid-ships there is a cabin with the chart table and a stand-by area forward of the main companionway steps. In front of this is the galley and dining area.

Above decks Maiden Hong Kong sports a 38m tall rig and this is the first rig on a 'G-class' boat - maxi mono or multihull - that not only rotates but can be canted up to weather. Cord of the mast is 680mm, of similar proportions to the spar on Olivier de Kersauson's trimaran Geronimo. It too is built from a single skin in high modulus M46J carbon fibre, rather than having a core. The result is slightly heavier but more robust.

Such a powerful rig must be stayed on a wide shroud base and even with a beam of 8m with her wings Maiden Hong Kong is still substantially narrower than a multihull. As a result the rig is fitted with deck spreaders similar to those of an Open 60. The deck spreaders are fixed to the hull and the hydraulic rams are attached to the shrouds above the deck spreaders, enabling the rig to be canted by up to 7 degrees. This is less than some of the 60ft trimaran rig that can cant to 10 or 11 degrees, and is limited by the beam of the boat. Beyond this, Kouyoumdjian says, the runner would start trying to bring the mast back towards the centre line. Standing rigging is in lightweight PBO made by Future Fibres.

The deck spreaders will also be used as a point from which to trim the headsails outside the physical limits of the boat. Kouyoumdjian said he considered having the deck spreaders cant with the mast instead of with the hull, but this would present problems with the genniker sheeting point as the leeward outrigger moved up and down in respect to the hull.

Kouyoumdjian received considerable help in the rig design from Swiss 60ft trimaran guru and two time Route du Rhum winner, Laurent Bourgnon. "He helped me a lot with the connectivity of the rig and the philosophy of using a rotating canting mast. Laurent is really good. I enjoyed working with him a lot."

Bourgnon was able to lend his experience ironing out a number of issues such as the main sheet track which with a canting rig must have curvature in three dimensions (with a flat traveller and the mast canted there can be potentially hazardous occasions when the traveller won't budge down the track if a gust hits).

There are two other unusual aspects to Maiden Hong Kong's rig compared to those of the other maxi sloops: all her headsails furling, with three forestays, the inner two removable and instead of being fitted with coffee grinders she uses powered winches, like Grant Warrington's Skandia.

"I see all these big boats with huge amounts of coffee grinders and connections and crews of 25 or more and there is this concept that it has to be human driven in order for records to be valid," explains Kouyoumdjian. "However Frank [Pong] has adopted a completely different philosophy. He says if records can validated when everything such as the canting keel or the water ballast is powered, then why not the winches? It makes no sense otherwise. And secondly, he does the records for himself. If the highest authority doesn’t want to recognise those records - who cares?" Fair point. Would water ballast or canting keel systems have moved beyond Minis or small boats, where systems are small enough to be operated by hand, if powered systems had been banned from the outset?

With furling headsails and push button-operated winches Maiden Hong Kong will not require a huge army of crew. Kouyoumdjian reckons she could easily be sailed by six and it is unlikely more than 10 would ever be needed. She could even be sailed singlehanded!

As a result of the small crew and the lack of coffee grinders the cockpit is more Open 60 than maxi boat. The cockpit sole is deep and the cabintop has been designed to deflect wind from the crew. "The apparent speeds will be very high and for long period of time it is not very nice to be sailing in all that wind - It like living inside a wind tunnel and people can't hear each other," says Kouyoumdjian.

Performance-wise the boat is expected to to be constantly sailing faster than wind speed, her VPPs showing the boat reaching at 28-29 knots with peaks of 30-31 knots in 20 knots of wind. Upwind the boat will do 13.2 knots in flat water although in practise this will be closer to 10-10.5 knots.

Sailing at such speed the apparent wind angle will rarely be aft of the beam. "Downwind for me is an apparent wind angle of 45-55 degrees. So it is designed for an apparent wind angle of 35-50 degrees - that is best VMG downwind. Downwind is becoming less and less of sailing yacht reality really and so it should be," says Kouyoumdjian.

At present the first event Maiden Hong Kong is scheduled to take part in is the Raja Muda in November. Over the southern hemisphere summer the boat will undergo further sea trials before heading for New York and the Rolex Transatlantic Challenge in May. In this she will line up for the first time against Robert Miller's all-conquering Mari Cha IV, the present monohull record holder for the North Atlantic.

Maiden Hong Kong will take part in other events around Europe during the summer before embarking on her first record attempts towards the end of 2005.

How the super-maxi competition looks:

	Alfa Romeo	Bols	Skandia	Zana	Morning Glory	Genuine Risk	Maiden Hong Kong	Mari Cha IV
LOA	27.43m	28.3m	30m	30m	26.63m	27.4m	36m	42.3m
LWL	24m	24.3m		25.4m	23.18m	25.53m		40.2m
Beam max	5.6m	6m	5m	5.25m	4.9m	4.45m	8m	6.5m
Draft	4.4m	4.8m		4.5m	4.5m	5m	6m	6.5m
Disp	22T	23T	26T	26.4T	21T	21.7T	30T	47.5T
Bulb weight		13.5T	14T	13.2T			13T
Mast height (off deck)	32m		36m	38m	31.2m		38m	45m x 2
Spar maker	Southern	Southern	Applied Composites	Southern	Hall	Southern		Southern
Sail area (upwind)	402	425		379.6	402.65	420	535
Sail area (downwind)	663	1000		874.4	872.18	615	700
Movable ballast	6T water	4.8T water	Swing keel (+/-15deg)	5T water	Swing keel	Swing keel (+/- 50deg)	Swing keel (+/- 35deg), 5T water	Swing keel, 10T water
Extra appendages	-	Transom flaps	-	Trim tab on keel	CBTF	CBTF-type	Forward foil with trim tab	-
Builder	McConaghy	BoatSpeed	Hart Marine	Hakes Marine, NZ	McConaghy	McConaghy	DK Yachts	JMV Composites
Designer	Reichel-Pugh	Hugh Welbourne	Don Jones	Bakewell-White	Reichel-Pugh	Dubois	Kouyoumdjian	Mari Cha design team
Sail maker	North Aus	Doyle NZ	Doyle Fraser	Doyle NZ	North San Diego	North		North NZ
Launched	Aug-02	Mar-03	Oct-03	Nov-03	Dec-03	Mar-04	Nov-04	Sept 03
IRC rating	1.711	1.745	1.61	1.61

If any designers/builders/skippers or project managers would care to update these figures or fill in the blanks please email us here