Introducing the Tennant cat PH8

PH
Paul Hotz
Thu, Feb 11, 2010 3:04 PM

Hello everybody,

Let me introduce myself.  My name is Paul, I am retired and live in
northern Italy, on lake Maggiore.

In my former lives I was a chemical engineer and also wrote software.
But that was what seems a long time ago.  For a while I lived in Los
Angeles where I had a motorsailer with which I went to Florida
(through the Panama canal) and then to the Caribbean (Bahamas,
Jamaica, Haiti, Mexico etc.).

When I retired I decided to build for myself a boat for the
Mediterranean and possibly a transatlantic crossing and back following
the canonical routes.  After much looking around and meeting Malcolm
Tennant in New Zealand I decided on an aluminum power catamaran
(probably the only one designed by Malcolm) derived from Malcolm?s New
Yorker.  A great help was also Alain Walker, Malcolm?s friend and
aluminum expert.

The reason I built the cat myself with a local crew was that I am an
inveterate tinkerer and wanted to put the blame on myself for any
mistakes and not have to live with mistakes made by somebody else.

So the PH8 was born.  It got launched in lake Maggiore in the Summer
of 2005, after four years of planning and building.  I then spent the
next two years on the lake outfitting and testing until in the Summer
2008 I divided the cat into an upper and a lower part and trucked it
to Cremona, where the Po river becomes navigable.

The cat is now based in Porto Levante, where an arm of the Po river
flows into the Adriatic.  After a few short cruises to Venice
(absolutely beautiful seen from one?s own boat) last Summer I cruised
Croatia and South Italy.

I am very please how the cat performs.  Here are its main characteristics:

LOA 16.5 m (54?2)
LWL 15.17 m (49?8)
Beam 6.78 m (22?3),  a bit narrower than the New Yorker
Hull beam 1.14 m (3?9)
Maximum displacement 30,000 kg (66,000 lbs).
Two Cummins 270 HP (198 kW) diesels.

At the water level the hulls are really narrow, to maximise the
efficiency and I cannot complain, burning at the hull speed of 9.5
knots and fully loaded about 25 liters /hr (6.6 USG/hr), which then
gives me a theoretical range of 2368 nautical miles, with my two tanks
holding altogether 6,482 liters (1,715 USG).

Maximum speed WOT is about 17 knots, but fuel consumption climbs to
over 70 l/hr for both engines, fuel consumption I consider a waste of
fuel and money.

I am also pleased how the cat handles in various seas, even though I
have not been in a real blow.  One of the more remarkable experiences
was with a following sea mantaining a speed of 10 knots and then surf
down a wave and hit 15 knots without touching the power levers.  A few
times I could feel the center keel doing its job, but the autopilot
never let the cat veer more than 1 degree to either side.  Of course,
if you are beam to a sea, when the period of the waves is just right,
the cat is plain hell and the only way out is to tack.  Most movements
of the cat are different from displacement boats, both at rest and
underway and it takes some time to get used to them, but now I could
not go back to the old ways.

Power to the propellers is transmitted to thrust absorbing Aquadrives.
It would have been almost impossible to properly align the engines
directly to the prop shafts considering that between the hulls and the
engines in places there are only a few centimeters.  Altogether I find
that on a modern boat of this power range an Aquadrive or equivalent
is an expensive piece of equipment that pays for itself just by
eliminating the pain in the you know where of alignment.  Also I can
take out the CV joint and disconnect the exhaust in about 30 minutes
and lift up an engine, a must feature when there is little space
around them for maintenance.

One of my only points of disagreement with Malcolm was his fondness of
variable pitch props.  I find them very expensive and one more
mechanical item that can break down.  Ok, this statement will put me
in hot water, but a famous Italian propeller manufacturer, eliche
Radice, that built my props, maintains that his props are way more
efficient than variable speed ones.  Granted, it is a very biased
view, but I believe him when I look at my carefully crafted props.

As for layout, since I like my creature comforts, I have two big
cabins with two big bathrooms, both with a bidet.  There is a sofa
that can turn into a bed on the bridge, but I don?t intend to cruise
with more than four for longer periods.  The kitchen, aft, is
furnished with standard IKEA cabinets and appliances.  They are cheap
enough that should they rot they can quickly be replaced.

The hulls are used exclusively for the engines, tanks, generator,
watermaker, heating and cooling equipment.  No such thing as to try to
squeeze a shower or an additional cabin into them. That makes all the
equipment easily accessible for maintenance.

The radar is Furuno, while all the other electronic equipment is
Raymarine.  The two systems are independent from each other.  An
ordinary PC with a household monitor completes the electronics.

On the upper deck there is a 3.6 m rigid bottom inflatable, with a 2.5
HP outboard.  For safety there is also an 8 persons SOLAS type life
raft.

I don?t have a flybridge, since the cat is ?drive by wire? and a
handheld remote control lets me drive from wherever I want to be.

The main anchor is a 55 kg Rocna, attached to 100 m of 12 mm
galvanized chain.  It is big enough since when I moved it to the cat
in the marina people started to laugh!

These are just the main features of a boat that performs well, I am
very proud of, ready to take me in comfort anywhere (well, within
reason).

If you want to see pictures, more specifications, read my old
adventures, visit me on my web site www.caracolyachts.com.  I?ll be
more than happy to answer any questions.

Or better still, if you happen to be near Venice, come to see me.

Paul Hotz
Power catamaran PH8
Porto Levante, Italy
www.caracolyachts.com

Hello everybody, Let me introduce myself. My name is Paul, I am retired and live in northern Italy, on lake Maggiore. In my former lives I was a chemical engineer and also wrote software. But that was what seems a long time ago. For a while I lived in Los Angeles where I had a motorsailer with which I went to Florida (through the Panama canal) and then to the Caribbean (Bahamas, Jamaica, Haiti, Mexico etc.). When I retired I decided to build for myself a boat for the Mediterranean and possibly a transatlantic crossing and back following the canonical routes. After much looking around and meeting Malcolm Tennant in New Zealand I decided on an aluminum power catamaran (probably the only one designed by Malcolm) derived from Malcolm?s New Yorker. A great help was also Alain Walker, Malcolm?s friend and aluminum expert. The reason I built the cat myself with a local crew was that I am an inveterate tinkerer and wanted to put the blame on myself for any mistakes and not have to live with mistakes made by somebody else. So the PH8 was born. It got launched in lake Maggiore in the Summer of 2005, after four years of planning and building. I then spent the next two years on the lake outfitting and testing until in the Summer 2008 I divided the cat into an upper and a lower part and trucked it to Cremona, where the Po river becomes navigable. The cat is now based in Porto Levante, where an arm of the Po river flows into the Adriatic. After a few short cruises to Venice (absolutely beautiful seen from one?s own boat) last Summer I cruised Croatia and South Italy. I am very please how the cat performs. Here are its main characteristics: LOA 16.5 m (54?2) LWL 15.17 m (49?8) Beam 6.78 m (22?3), a bit narrower than the New Yorker Hull beam 1.14 m (3?9) Maximum displacement 30,000 kg (66,000 lbs). Two Cummins 270 HP (198 kW) diesels. At the water level the hulls are really narrow, to maximise the efficiency and I cannot complain, burning at the hull speed of 9.5 knots and fully loaded about 25 liters /hr (6.6 USG/hr), which then gives me a theoretical range of 2368 nautical miles, with my two tanks holding altogether 6,482 liters (1,715 USG). Maximum speed WOT is about 17 knots, but fuel consumption climbs to over 70 l/hr for both engines, fuel consumption I consider a waste of fuel and money. I am also pleased how the cat handles in various seas, even though I have not been in a real blow. One of the more remarkable experiences was with a following sea mantaining a speed of 10 knots and then surf down a wave and hit 15 knots without touching the power levers. A few times I could feel the center keel doing its job, but the autopilot never let the cat veer more than 1 degree to either side. Of course, if you are beam to a sea, when the period of the waves is just right, the cat is plain hell and the only way out is to tack. Most movements of the cat are different from displacement boats, both at rest and underway and it takes some time to get used to them, but now I could not go back to the old ways. Power to the propellers is transmitted to thrust absorbing Aquadrives. It would have been almost impossible to properly align the engines directly to the prop shafts considering that between the hulls and the engines in places there are only a few centimeters. Altogether I find that on a modern boat of this power range an Aquadrive or equivalent is an expensive piece of equipment that pays for itself just by eliminating the pain in the you know where of alignment. Also I can take out the CV joint and disconnect the exhaust in about 30 minutes and lift up an engine, a must feature when there is little space around them for maintenance. One of my only points of disagreement with Malcolm was his fondness of variable pitch props. I find them very expensive and one more mechanical item that can break down. Ok, this statement will put me in hot water, but a famous Italian propeller manufacturer, eliche Radice, that built my props, maintains that his props are way more efficient than variable speed ones. Granted, it is a very biased view, but I believe him when I look at my carefully crafted props. As for layout, since I like my creature comforts, I have two big cabins with two big bathrooms, both with a bidet. There is a sofa that can turn into a bed on the bridge, but I don?t intend to cruise with more than four for longer periods. The kitchen, aft, is furnished with standard IKEA cabinets and appliances. They are cheap enough that should they rot they can quickly be replaced. The hulls are used exclusively for the engines, tanks, generator, watermaker, heating and cooling equipment. No such thing as to try to squeeze a shower or an additional cabin into them. That makes all the equipment easily accessible for maintenance. The radar is Furuno, while all the other electronic equipment is Raymarine. The two systems are independent from each other. An ordinary PC with a household monitor completes the electronics. On the upper deck there is a 3.6 m rigid bottom inflatable, with a 2.5 HP outboard. For safety there is also an 8 persons SOLAS type life raft. I don?t have a flybridge, since the cat is ?drive by wire? and a handheld remote control lets me drive from wherever I want to be. The main anchor is a 55 kg Rocna, attached to 100 m of 12 mm galvanized chain. It is big enough since when I moved it to the cat in the marina people started to laugh! These are just the main features of a boat that performs well, I am very proud of, ready to take me in comfort anywhere (well, within reason). If you want to see pictures, more specifications, read my old adventures, visit me on my web site www.caracolyachts.com. I?ll be more than happy to answer any questions. Or better still, if you happen to be near Venice, come to see me. Paul Hotz Power catamaran PH8 Porto Levante, Italy www.caracolyachts.com