Text by Mike Rose
BEST OF BOTH WORLDS
Combining an aluminium hull, GRP superstructure and Tectrax amphibious system, Fenton Marine’s new 770 AMPH is an impressive performer both on and off the water.
Few boats attract as much attention at the ramp as did the new Fenton Marine 770 AMPH. I suspect that could be because it doesn’t look like a conventional amphibious boat. Instead, it seems more like a very classy, stylish cruiser that just happens to sit on three wheels rather than a trailer.
Designer and builder Nick Fenton say both he and the vessel’s owner were adamant that the 770 AMPH had to work as well as a “proper” boat as it did as an amphibious one.
The Fenton 770 AMPH is Nick’s first amphibious design (he also produces the Tino range of RIBs and the Flyfin range of alloy boats), and he says he spent a lot of time listening to its owner and understanding what he wanted.
“I then designed the 770 from the keel up, spent more time with the owner and kept modifying it until we were both satisfied. We even built a full-size mockup before finalising the design.”
The result is a truly amazing vessel and surely one of the most innovative on the market. Not only does it feature an amphibious system that allows it to “squat” on the beach, but it also features a stabilising gyro and a bimini-style hardtop that can be lowered electrically to below the level of the windscreen to fit in a 2.1m garage.
Powerful performer
To ensure the boat performs as much as possible like a typical alloy vessel, the Tectrax system’s front wheel lives in its pod well above the waterline while the rear wheels tuck away under the transom and are shielded by the hull.
The result is a boat that performs not just like a regular boat but more like a performance craft. With a 300hp Mercury V8 on the back, it leaps onto the plane, gets swiftly to its cruising revs, handles like a dream and, despite displacing three tonnes, effortlessly hits a top speed of 39.2 knots.
Acceleration through the range is immediate, and when turning, even quite tightly, there is no hint that three large wheels are hanging off the ends.
As the accompanying figures show, there are some sweet spots in the speed/fuel burn range, with 4500rpm giving around 35% more speed over 4000rpm for just an extra litre per hour. It’s almost as impressive at 5000rpm where the extra 500 revs give nearly 43% more speed for just 27% more fuel used.
The 770 is also fitted with a Quick X3 gyro stabiliser. Requiring its own bank of batteries, the X3 has a very quick spool up to stabilisation time of 8mins and just 15mins spool up time to rated RPM. The anti-roll output torque of the X3 is an impressive 3900N-m. Very impressive from such a tiny little machine that is just 42cm square and takes up minimal space in the 770.
We drive fast in tight circles with a dead flat harbour to create some good-sized waves before dropping off the plane and waiting for them to hit. It is an eerie feeling when they do. One braces and waits for the rocking to start and then feels rather foolish. Despite the waves approaching from the beam on, the side to side movement is barely discernable. I imagine for those who suffer from mal de mer, it will seem a godsend.
On the beach
Climbing out of the water and onto the beach, the 770 AMPH proves even more of a drawcard than it did on the ramp. It also allows Nick to show off another of the Tectrax’s features: the camera mounted above the front wheel.
Mounted high in the front wheel pod, the camera, its feed displayed on the Raymarine MFD 12in screen, captures both the wheel and its position and the seabed below. This enables the operator to ensure that the wheel is fully engaged and that no nasty surprises are waiting below the water.
Deploying the wheels, switching between their motive power and that of the outboard and raising the latter to safely is an operation requiring good timing and a fair degree of concentration. Nick, who has now done it multiple times, says it gets easier with practice.
Once on the beach, the Tectrax system also can go down on its wheels so that the hull is sitting snugly on the sand. This makes it easier for those on board to get on and off the boat more easily without using the stern ladder.
Looking sharp
One of NZ’s most respected trailer boat manufacturers used to stress (and probably still does) that for a design to have broad appeal, it has to look like it is doing 40 knots, even when sitting on its trailer.
Swap trailer for wheels, and you have a pretty good description of the 770 AMPH. Better still, it matches that sleek, swept-back look with an incredibly high standard of finish. Protecting the striking Bryon Blue metallic hull, topsides and transom are an impressive eight coats of clear. The superstructure, hardtop, and those portions of the interior not fitted with either solid teak or Flexi-teak have been painted in Awlcraft Mercury Cold Fusion to match the outboard.
One of the most eye-catching sections of the 770 is the large aft platform. Here, the intrusion of space to accommodate the aft wheel assemblies has been turned into a positive, the wheel arches on each side becoming attractive cascading semi-circles that follow the Portofino stern curve. With protective pushpits and a 2.75m beam, the platform still offers plenty of space from which to fish, and these arches provide a comfortable place to perch when the action is slow.
There is little doubt that the 770’s owner is a keen fisher. There is a bait tank in the port transom (its height making it far easier to access than those installed under transom steps). The Fenton custom bait board includes reversible timber inserts and a sink underneath, draining cleanly out under the platform. The bait board also features a handy Raymarine Axiom 9” MFD, a repeater for its larger sibling in the dash.
Serious battery power
With both an amphibious system and a gyro stabiliser on board, the 770 needs a relatively sophisticated electrical management system. The engineering and batteries required to power it all takes up a reasonable amount of space.
With so much extra weight on the boat, its distribution is critical, and Nick has chosen to spread it between a large transom locker and a centrally positioned one under the cockpit. In the former life, the dual boat batteries, Victron AC/DC and DC/DC chargers, the Blue Seas remote battery system and the Tectrax control boxes. Housed beneath the cockpit are the lithium batteries and the rear wheel up/down controls for the Tectrax system, along with the 500a/hr bank of four AGM batteries required to run the gyro.
Other electronics onboard include Zipwake auto trim tabs, a CZone digital switching system linked to the Axiom MFD, a Maxwell Tasman drum winch and the Fusion stereo system.
Seating options
Those on board have plenty of options when its time to relax. There are the twin custom-made King/Queen seats with composite back supports for the former and space to accommodate chiller boxers under the latter. There are fold down side seats in the cockpit (like the transom hatches, all CNC manufactured by Fenton Marine) and loads of space in the cabin, which also houses a TMC head and a privacy curtain.
Although it’s not apparent at first glance, the 770 is also a complete, well-protected walkaround. Thanks to its wide timber steps, anodised scuppers to stop water running back into the cockpit and rod and drink holders, it is ideal for those wanting to soft bait or wanting unimpeded movement when fighting large pelagics.
Any, finally, if there wasn’t enough innovation on this vessel already, Nick has designed a carbon fibre and GRP hardtop that can be electrically lowered below the level of the windscreen so the 770 can live underneath its owner’s pole house.
Summary
Fenton Marine’s first foray into the fast-growing amphibious boat market is an impressive debut. No follow-the-leader copycat, this is an innovative, clever design, stylishly executed. Although its owner lives just a short distance from the nearest boat ramp, the 770 AMPH’s system allows him 25 minutes of on-land on a hard surface. That is more than enough to launch his boat, visit (i.e. run up onto) a few nearby beaches and return home.
Add in the gyro stabiliser, the hydraulic hardtop, the sleek looks and stunning finish — and the powerful performance — and this is a boat that will attract attention. A lot of attention.
Specifications
- Boat Design Name: Fenton Marine 770 AMPH
- Builder: Tino Marine
- LOA: 8.25m
- Beam: 2.75m
- Height On Trailer: 2.05 (Roof Down)
- Deadrise: 17°
- Construction: Plate Aluminium, Composite super structure
- Towing Weight: 3500kg
- Amphibious System: Tectrax
- Fuel Capacity: 200ltr
- Engine Range: 300-500hp
- Test Power: Mercury 300hp Verado
- Max Speed: 39 knots
- MFD: RayMarine
- Trim Tabs: Zipwake
- Gyro: Quick MC
- Sounds: Fusion
- Priced From: $NZ POA
- Price as Tested: $NZ POA
| RPM | Knots | L/h | L/NM | Range (NM) |
| 1000 | 4.1 | 4.6 | 1.2 | 150 |
| 1500 | 6.1 | 7.2 | 1.2 | 150 |
| 2000 | 7.2 | 11 | 1.6 | 110 |
| 2500 | 8.6 | 16 | 1.9 | 94 |
| 3000 | 9.7 | 24 | 2.5 | 72 |
| 4000 | 15.1 | 40 | 2.7 | 66 |
| 4500 | 21.5 | 46 | 2.2 | 81 |
| 5000 | 28.7 | 58 | 2.1 | 85 |
| 5500 | 34.8 | 74 | 2.2 | 81 |
| 6000 | 39.2 | 90 | 2.3 | 78 |
