Ribco Venom 44: Premium RIB w/1,200 HP
Report courtesy of e-ribbing.com.
Ribco Marine is a Greek company that is dedicated to making high-quality and innovative designs with luxurious features. Now more than 20years old, Ribco Marine is a highly respected brand in the Med and has built more than 500 of these large, multi-purpose RIBs. Thanks to BoatTEST’s partner in Greece – e-Ribbing.com – we are able to bring to you an authoritative, in depth report on Ribco Marine’s Venom 44, a rigid hulled inflatable that can do most anything
With over two decades of experience, the founders of Ribco Marine remain loyal to their original vision: the design and construction of offshore-oriented RIBs characterized by their seaworthy hulls, on which a luxurious "Mediterranean" deck is built with a high level of design and equipment, meticulous to the last detail.
This is the biggest reason why Ribco Marine is constantly investing in research and development, thoroughly testing its boats before their production while all stages of construction take place at the yard under the constant supervision of strictly selected and trained personnel.
The New Flagship
Featuring 11 different models from 23’ to 44’ (7.01 m to 13.41 m), Ribco provides a range of multi-use RIBs for buyers who appreciate quality, safety and seaworthiness. The Venom 44 is the company’s flagship with an overall length of 43’2” (13.15 m) and she runs on a hull designed by Lorne Campbell. It has three steps, a double chine, two spray rails, a built-in bracket, a 23-degree deadrise angle at the transom.
On Deck
At first glance, the Venom 44 captivates and prompts dreams. From stem to transom, she is designed with ergonomics and functionality in mind using quality materials while all the accessories are inspired, designed and made in house to combine luxury with individuality.
The Venom 44 has an aristocratic finesse that could make her ideal for tender luxury yachts. She can also accommodate four people in large berths hidden under the sundecks in the bow and stern.
The Bow
The entire bow is adorned in high-quality teak. Its aggressive lines and simple, quality equipment combined with the excellent fit and the unique finish of the tubes set a high bar to imitate.
The small, elegant hard nose just protrudes from the confluence of the tubes and matches harmoniously with the superstructure of the bow, giving the necessary step to enter or exit the boat.
Recessed cleats are positioned without any risk of injury and a hatch in the foredeck gives access to a limited storage space. Just aft is another hatch that leads to the space that houses the windlass. The stainless-steel rode and anchor that exits through the stem.
The Forward Cabin
Abaft lies the forward sunlounge, with a total length of 8’6” (2.63 m) and a maximum width of 6’3” (1.90 m). At its back there is the large hatch that is raised with an electro-hydraulic mechanism and reveals the large double berth below. It measures 6’5” (1.95 m) long and 6’2” (1.88 m) at its widest.
The Console/Head
A little more than 39” (100 cm) abaft the bow sundeck is the console. The large single seat on the front can be raised to reveal the private head compartment. Inside, the area has dimensions of 4’11” x 3’7” x 6’ (1.50m x 1.10m x 1.82m) forms a very spacious head equipped with faucet and sink, shower and electric toilet.
Two hatches in the back of the enclosed head, give the necessary access to the electrical installation of the console resulting in complete control and comfortable inspection of the cables and the invisible sides of the devices.
The console is centrally located, with its side surfaces converging towards the deck so as to leave comfortable passageways to its post and starboard, with a maximum width of 19” (48 cm) for the easy passage of the occupants.
The Helm
The instrument panel is made of carbon fiber and has an ideal inclination for easy, direct reading of the screens underway even when we choose to drive in an upright position. The driving position is properly set and ensures excellent visual contact with the bow. Finished perfectly, it has plenty of space for the installation of large multifunction displays with conventional engine-monitoring instruments above.
The steering wheel is located on the port; in the center is the 16” (40.64 cm) Raymarine screen. To starboard, there is a small locker for placing small items and charging mobile phones.
It is worth noting the design of the polyester construction that rests on the console extending between the helm seat and where the engine controls are based.
The two independent helm seats are characterized by their large backrests that embrace the whole body, have a damping mechanism with adjustable height while providing good lateral support that appreciated when attempting tight maneuvers.
The Cockpit
Behind the independent helm seats, there is a large three-seater sofa under which the boat's refrigerator and the sink are housed. Further back, an elegantly designed two-seater sofa faces the stern, increasing the lounge capacity in the cockpit, which is the main gathering place of the RIB.
Under the two independent sofa seats, there are two small separate storage compartments where the fuel selection valves of the boat's triple tanks are located. Further back, the table is placed that transforms the stern lounge area into a large dining one where six adults can comfortably sit.
And of course it would be a great omission if we did not mention the T-top that in combination with the crystal windshield offers excellent protection from wind, rain and spray. Apart from the protection, the T-top is one of the strongest elements of the Venom 44 that matches harmoniously with the overall layout. It’s made entirely of carbon fiber, weighs at least 220.46 lbs. (100 kg) less than a conventional one and of course keeps the center of gravity of the boat lower. This is a masterpiece that demonstrates the high standards of the yard.
The Stern
The stern sofa, with a width of 7’5” (2.26m) can comfortably accommodate four adults, while in its center it leaves a useful passageway for our movement to the stern.
The same useful passageway is formed in the aft sunbed that measures 5’11” (1.80 m) long and 7’9” (2.35 m) wide. Beneath, there is a huge storage space that can easily be converted into a cabin where two adults can comfortably spend the night. On the test boat, the lines and the fenders were stored and we found a small hatch that gives access to the excellent quality valves of the deck drainage pipes.
Further back, we find the swim platform which, with the exception of the stern anchor, is free of piping and obstacles that restrict freedom of movement and carry a risk of injury. On its port side are the recessed ladder and stainless steel grab handles that assist in reboarding.
However, access to the boat when docking with the stern is not an easy task and requires the use of a gangway. With the installation of two engines instead of three that were installed before the release of the new 600-hp Mercurys. Given the even greater space saving that they provide due to the steerable gearbox, it is possible to increase the surface and extend the swim platform to the port and starboard so as to offer direct access to the boat.
At Sea
Escape to the freedom of Big Blue without compromise. That would be the title I would put after the long and hard sea trial we put the Venom 44 through.
We waited just a few minutes for the engines’ oil temperature levels to rise and immediately nailed the throttles forward to see the final speed so that the level of our own temperature would also rise because the cold was quite intense. Windshield protection was ideal and of course absolutely necessary for winter excursions.
The view of the bow and the horizon from the helm seats was unobstructed and Venom 44’s bottom manage the speedy ride with comfort while keeping its course steady. It is worth noting that the 68.1 knots come easily, without any special effort from the pilot. The boat "travels" with absolute control and safety at this speed, while maintaining the proper attitude, which stems mainly from the ideal weight distribution of the RIB.
I confess that it took me a long time to realize that I was able to develop such a great speed with a 44’ (13.41 m) RIB, something that I honestly did not expect. A result that is due to the long pitch of the propellers, something that is credited to the wonderful geometry of the hull that reduces the load on the engines. This lets them reach their maximum rpm limit in combination with a feeling of the boat being properly balanced.
The Numbers
Our test boat was equipped with twin 600-hp 7.6L Mercury V12 Verado outboards that have a maximum rpm limit of 5600-6400 and a gear ratio of 2.50:1. They were turning 35” (88.9 cm) pitch Mercury dual propellers.
The 600-hp Mercury engine is a mechanical marvel with built-in electro-hydraulic steering system, two-speed automatic transmission, steerable gearcase that can turn 15 degrees more than normal and contra-rotating dual propellers. With 132.09 gallons (500 liters) of fuel, four crew members and all the equipment of the boat we headed out of the Anavyssos bay.
On the day of our sea trial, weather conditions were very good, so we could not evaluate the RIB at high wave height. Still, given the length and geometry of its hull and the company’s reputation, we expect she will have strong ability to manage in bad weather conditions.
I know that most of the readers want the tests to take place only with bad weather conditions, but that is not always possible to plan.
In conditions of intense waves you can evaluate the degree of soft and dry cruising but nothing more. On the contrary, in ideal conditions, a captain can focus on the behavior of the boat to evaluate and measure more accurately the final speed, acceleration, slippage and cruising speed in combination with fuel consumption. He can also evaluate the throttle response, the boat's behavior at high speeds and in sharp turns and better understand how the boat stands on the water through the whole rpm range. A test driver can identify areas where he needs to intervene improving performance by selecting the most appropriate engine mounting height in conjunction with selecting the most appropriate propeller.
At 3000 rpm, we were traveling at 22 knots burning .98 gph (3.7 lpnm), while at 3500 rpm where the 2nd gear came in automatically, our speed climbed to 35 knots with a fuel consumption of just .86 gph (3.25 lpnm). At 4000 rpm, the fuel consumption dropped even further and reached .85 gph (3.2 lpnm) per mile while traveling at 41 knots. This was also the most economical cruising speed we recorded.
Without a doubt, the 3.2 liters of fuel consumption is an amazing number while the 41 knots, which is a very pleasant speed for this boat, let us cover long distances quickly and, above all, comfortably.
Traveling at this speed, we also achieve our maximum autonomy that is 156 nautical miles with 132.09 gallons (500 liters) of fuel on board, so an owner won’t have to drain his/her credit card for fuel. If we now consider that the total fuel capacity of the boat is 277.39 gallons (1,050 liters) then we can easily calculate the total autonomy of the Venom 44, of course adding a few more liters of consumption, which certainly reaches 300 nautical miles.
At 4500 rpm we ran 46 knots, consuming 1.02 gph (3.9 lpnm), while at 5000 rpm our speed was 52 knots with the engines starting to thirst more, drinking 1.11 gph (4.2 lpnm). At wide open throttle, Venom 44 reached a staggering 68.1 knots with engines swallowing 1.56 gph (5.9 lpnm), reaching their max rpm limit.
Although I do not belong to the category of those who seek the maximum top speed, I would try to put the engines with longer propeller pitch a hole higher having a high probability of breaking the 70 knots barrier.
The RIB held plane at just 2400 rpm with a speed of 13 knots, which permits travel in heavy weather conditions, thus maximizing our autonomy. Throttle response was immediate while the accelerations across the rpm range was explosive with the Venom 44 reaching 30 knots in 6.3 seconds, 40 knots in 9 seconds and 50 knots in 11.2 seconds.
It is worth noting that the flexibility as well as the steer-ability, cornering properties and turn-ability of the Venom 44 made us feel like we were riding a much smaller boat making our cruise particularly enjoyable.
Ride quality was excellent through the power band with the boat standing perfectly on the water and responding immediately to every maneuver we attempted. This gave us absolute confidence and safety even when we pushed it to its limits. Taking a closer look at our measurement table, we find out the low slip values we recorded even at lower rpm. This combined with the engines reaching their maximum rpm demonstrate an ideal setup. The low slip numbers are mainly a result of the dual contra-rotating propellers that offer the maximum possible stern lift.
The dual-prop system may be more complex, with increased cost of purchasing propellers but also increased maintenance required compared to standard single ones, but the benefits are multiple. Contra-rotating propellers are theoretically up to 20% more efficient, mainly due to the larger number of blades and the significantly larger total blade area. This results in increased stern lift and reduced wet surfaces, significant reduction in slip, increased cruising speed and reduced fuel consumption. They are , them ideal for moving large or heavy-loaded vessels. In addition, contra-rotating propellers reduce possible cavitation problems while minimizing vibration.
Venom 44 Performance
Also, given that the length of the hull is the second main factor that determines the size of the propeller, it becomes clear that the dual-prop system is one-way especially for twin-engine applications in boats longer than 40’ (12.19 m).
As we have mentioned many times, it is not the horsepower that ultimately propels a boat but the thrust generated by the propellers, which must overcome those forces that are trying to slow it down or stop it.
Evaluating the recorded measurements, we can only accept that the Venom 44 with the powerful Mercury engines is a top combination in terms of cruising speed, top-end, fuel consumption and slip rates. The performance combines with a high degree of ergonomics, functionality, finish and aesthetics that will be very difficult to compete within the global market.
RIBCO Marine
178 Ag. Marinas Koropiou Ave. – 19400 Koropi - Athens
Tel. +30 22910 90800