H2X YACHTS: MCAT 88' (brian eiland)

JW
John Winter
Mon, Sep 3, 2007 11:52 AM

H2X: Wow, what French flair! I just love what they do with accents!
We built an 86 footer 4 years ago (Pacific Harmony
http://www.adventurebay.co.nz/pacificharmony.htm ) so I'll throw in a few
views to fire up some wake up discussion.
Impressive colour scheme and very daring to go Waterjets on what looks to be
a displacement hull converted for the jets. Still looks to be squatting in
the running shots however. Tunnel clearance shortage gives away what looks
to be a little of a weight problem. Watch out for an attempt at a set of
foil fixes to get lift and send her up and away along with some hard chine
add-ons.
Our full displacement canoe body 86 x 28 footer turned out around 60 tons VS
74 tons for their 84x34 footer and we thought we were heavy. Their designer
states 64 on his site and the builder 74 on his so it is 10 tons overweight
which is an issue, even with its beamy hulls. We still managed 25kts on half
the power- Caterpillar 800hp/side despite design suggestions of 28 which I
have since learned are a little out of reach on canoe body pure displacement
hulls of most lengths. Our speed to power performance I rated as quite good
for multi's this size but I was never happy with the super skinny hulls and
zero space engine rooms. Sliding underneath a hot engine mid-Pacific to
reach the other end for an alternator repair was not my idea of serviceable.
The bilge oil helped lubricate my 85kg frame up there but removing the
alternator with it jammed in your stomach on an 86 footer has to be
questioned! I since learned other designers were getting the same figures as
us with generous hull width, walk around engines, and less blue water
pitching. Hence our new boat has widened up considerably. I also gave up on
the double barrel tunnel effect, 2 much smooth area and a cupping effect
when trapping the waves. Nic De Waal and Peter Brady's theory looks sensible
now with hard chine multi-ridge tunnels to break up the spray. Nic's hulls
certainly turn the roughest water into toast (with honey!)
JETS: With the H2X, MAN 1300cv'S they would probably have liked 5 more
knots, and on a foil assisted planing hull they would have got it with very
little difference under 10kt in fuel. If you are throwing over 3000hp in a
boat, you wouldn't be concerned over a few litres per hour extra fuel at 10
kts. Range figures on the builder site are around 1/3 the Yacht Forum site
posted and lower than I'd expect in this power-rig, 1000 miles with 7000
litres@10kts. (30 kts- here to the first tanker?)
Jets are always going to give poor economy in the 10-20 range but usually
quite good performance over 25, unbeatable over 35 if you have the right
hull shape- lifting on foils with reduced drag to let her fly. Under 10kts
foil/jet powercat owners tell me they are still quite good, especially on
one engine (no prop drag) so the above numbers don't quite stack up.
The attraction of ultimate anchoring spots in shallow waters and unlimited
docking moves give the jets a strong argument if you like a fast cruise
speed. We are staying with displacement/shafts on our next cat and then
going foil-planing/jets the following one for some white knuckle
passagemaking. (The kids have to be a little older first!)
Don't you just love the creativity of the French Interiors? Island berths
for the guests on this size would be nice but usually island guest berths
need to creep across the wing deck and make a multi-level interior, some
don't like that. The chic interior design really looks sharp! (Perhaps a
little sharp if you land on it one rough day) Style is all about minimalism
and square these days.
John Winter
www.adventurebaypowercats.com

H2X: Wow, what French flair! I just love what they do with accents! We built an 86 footer 4 years ago (Pacific Harmony http://www.adventurebay.co.nz/pacificharmony.htm ) so I'll throw in a few views to fire up some wake up discussion. Impressive colour scheme and very daring to go Waterjets on what looks to be a displacement hull converted for the jets. Still looks to be squatting in the running shots however. Tunnel clearance shortage gives away what looks to be a little of a weight problem. Watch out for an attempt at a set of foil fixes to get lift and send her up and away along with some hard chine add-ons. Our full displacement canoe body 86 x 28 footer turned out around 60 tons VS 74 tons for their 84x34 footer and we thought we were heavy. Their designer states 64 on his site and the builder 74 on his so it is 10 tons overweight which is an issue, even with its beamy hulls. We still managed 25kts on half the power- Caterpillar 800hp/side despite design suggestions of 28 which I have since learned are a little out of reach on canoe body pure displacement hulls of most lengths. Our speed to power performance I rated as quite good for multi's this size but I was never happy with the super skinny hulls and zero space engine rooms. Sliding underneath a hot engine mid-Pacific to reach the other end for an alternator repair was not my idea of serviceable. The bilge oil helped lubricate my 85kg frame up there but removing the alternator with it jammed in your stomach on an 86 footer has to be questioned! I since learned other designers were getting the same figures as us with generous hull width, walk around engines, and less blue water pitching. Hence our new boat has widened up considerably. I also gave up on the double barrel tunnel effect, 2 much smooth area and a cupping effect when trapping the waves. Nic De Waal and Peter Brady's theory looks sensible now with hard chine multi-ridge tunnels to break up the spray. Nic's hulls certainly turn the roughest water into toast (with honey!) JETS: With the H2X, MAN 1300cv'S they would probably have liked 5 more knots, and on a foil assisted planing hull they would have got it with very little difference under 10kt in fuel. If you are throwing over 3000hp in a boat, you wouldn't be concerned over a few litres per hour extra fuel at 10 kts. Range figures on the builder site are around 1/3 the Yacht Forum site posted and lower than I'd expect in this power-rig, 1000 miles with 7000 litres@10kts. (30 kts- here to the first tanker?) Jets are always going to give poor economy in the 10-20 range but usually quite good performance over 25, unbeatable over 35 if you have the right hull shape- lifting on foils with reduced drag to let her fly. Under 10kts foil/jet powercat owners tell me they are still quite good, especially on one engine (no prop drag) so the above numbers don't quite stack up. The attraction of ultimate anchoring spots in shallow waters and unlimited docking moves give the jets a strong argument if you like a fast cruise speed. We are staying with displacement/shafts on our next cat and then going foil-planing/jets the following one for some white knuckle passagemaking. (The kids have to be a little older first!) Don't you just love the creativity of the French Interiors? Island berths for the guests on this size would be nice but usually island guest berths need to creep across the wing deck and make a multi-level interior, some don't like that. The chic interior design really looks sharp! (Perhaps a little sharp if you land on it one rough day) Style is all about minimalism and square these days. John Winter www.adventurebaypowercats.com