Here are some commonly asked questions about Petestep
All planing boats, with speeds over 20 knots. Anything from PWC water scooters, to fast superyachts.
Petestel is not a stepped hull in the traditional sense of having transversal steps in the hull, to increase angle of attack and provide air bubbles under the hull surface. However, Petestep’s deflectors can be combined with a stepped hull to get the advantages from both worlds, if desired.
Petestep is working in close collaboration with the boat designer and boat builder to create the best possible boat. We are convinced that the synergies created by having people with different specialities are the future. By using our patent combined with detailed specifications of how the boat is intended to be used, as well as thorough weight calculations and advanced performance simulations, Petestep can optimize a boat model further than other hull designers and Naval Architect firms.
Yes, we have done over 250 full scale tests, and driven around 100 different prototype versions based on 24 foot sport boats with outboard engines. We have always measured the boats’ running attitudes, motions, GPS-data etc, and analyzed the data as reference to our simulation software.
We have also done specific research on the spray behaviour on V-bottom boats and its interaction with deflectors. On this topic, University studies have also been made, which verified our potential to reduce resistance.
Yes, all conventional propulsion systems work with Petestep deflectors.
We model the boat using over 50 parameters, including deadrise angle, weight, Center of Gravity, projected aerodynamic area, etc. All forces acting on the boat are calculated for a certain speed. This allows us to run the boat in multiple speeds and adjust the hull and optimize it for a certain boat and its usage. We use these results as input to our high fidelity CFD simulations.
Of course, every boat is a trade off. E.g. between weight, cost, performance and interior space. You can’t have it all. Therefore, a hull has to suit the boat model’s intended use. If the boat is a fast offshore military boat, it might be ok to be a little heavier and more expensive. On the other hand, it the boat is to be used by the mass market with friends on a lake a couple of times per year, it should probably have as much space as possible for the money.
When the concept is figured out and the priorities are set, all parameters of the boat should be optimized to get the best boat possible. The chine beam, center of gravity, deadrise, engine power, just to name a few parameters, are optimized to get the best performance possible. At Petestep, we use advanced computer simulations that considers the exact pressure distribution under the hull bottom, in order to create the best trade-off possible
Petestep is working in close collaboration with the boat designer and boat builder to create the best possible boat. We are convinced that the synergies created by having people with different specialities are the future. By using detailed specifications of how the boat is intended to be used, as well as thorough weight calculations and advanced performance simulations, Petestep can optimize a boat model further than other hull designers and Naval Architect firms.
In one way you should use as little engine trim as possible. A neutral trim will make the boat less sensitive to waves and will make it easier to steer at high speed. It is also true that if you trim the engine up or down a lot you will lose thrust. But in planing V-bottom boats, the most important thing is that the boat has a good angle of attack. As soon as you get over the hump, the bow will drop downward with increasing speed. But you want to keep the boat close to its optimum trim angle. This will require you to trim the bow down in low speed close to the hump, and bow up, at high speed.
Usually a good angle of attack is around 4 degrees, but it depends on speed. On Petestep boats, different deflectors are optimized for different angles of attack, at different speeds. If the engine trim is not used correctly, the deflectors will not be optimally functioning but they are designed to have better performance than a comparable spray rail hull in every situation.
All full planing boats can benefit greatly from a Petestep hull. However, the technology is such an integral part of a boat model that it needs to be in the design right from the start. The technology can’t be retrofitted or transferred between boat models. Manufacturers work in cooperation with us to develop a boat with the best possible comfort and performance. We make sure the hull is optimized for a particular model and put restrictions on the placement of equipment and tanks etc. Petestep charges a fee for the design and development, along with a license fee for each produced boat. Petestep keeps in regular contact with the manufacturers to ensure the boats are being produced according to the specifications.
More and more manufacturers are becoming interested in our technology. If you are a manufacturer and want to get in contact click here.
If you are a consumer, maybe your local distributor will have a Petestep boat soon. Next time you buy a boat, ask for one with a Petestep hull!
Any planing boat can be made softer, even without changing the deadrise angle. The beam is an important parameter here. If the beam is decreased by 10%, vertical accelerations will be decreased by about 20%. However, the boat will also lose side stability by more than 10%.
Petestep can make this design dilemma easier. If a boat uses a Petestep hull, it can be wider, have the same vertical accelerations and significantly increased side stability. Or, it can be just a little bit narrower and with a decrease in vertical accelerations by half, while having the same stability.
A boat can be made softer in waves in a variety of ways. However, each method leads to other effects:
- Less beam (decreases stability, increases hump speed and limiting space)
- Adding weight (linearly increasing fuel consumption)
- Increasing deadrise angle (increasing fuel consumption)
- Using Petestep technology (decreasing fuel consumption and quieter ride)
Decreasing the beam is often not a good idea because decreased stability and space is never desirable. To achieve a reduction of vertical acceleration (hardness of ride) by 30% using conventional technology by adding weight or increasing the deadrise angle, around 50% more energy is required and hence, 50% more fuel consumption.
Petestep technology always gives a boat a significantly softer ride, and/or significantly lower fuel consumption. We can make a boat ride over 30% softer, while also reducing the resistance by 5-10%. Compared to a boat with similar softness using conventional technology, resistance is now reduced by over 35%.