Hydrofoil Technology
Hydrofoil Design Services
Hydrofoilds for new-builds & retrofits to existing vehicles
Icarus Marine offers a full turn-key solutions for
- Hydrofoil design;
- Fabrication;
- Installation;
- Sea trial support.
For a variety of different craft:
- Hydrofoil supported catamarans;
- Hydrofoil supported trimarans;
- Fully flying hydrofoils with self-stabilizing fixed foils;
- Fully flying hydrofoils with electronic flight control.
We make extensive use of our own in-house design tools, CFD and tank testing for hydrodynamic design.
Our
Designs
Icarus has more than 30 years experience designing hydrofoils for vessels from 6m up to 45m in length in a variety of different materials.
Various options for the hydrofoils are available:
- Fixed foils with no moving parts;
- Foils with incidence control (the whole hydrofoil rotates to change the angle of attack);
- Foils with flaps;
- Manually adjusted during trials and then fixed;
- Electronically controlled (manual toggle switch or with motion control).
Click here to see examples.
Which Material?
Many different materials are available for hydrofoils. Below is our assessment of the pros & cons of the different materials.
All things considered, stainless steel hydrofoils provide the best balance of all factors. The price is reasonable and technical performance and reliability is high. There is a higher weight penalty than with other materials but because the weight of the hydrofoil is a small % of the boat weight this is not so important.
| Duplex stainless steel | Titanium | Carbon composite | Aluminium | |
| Strength | High strength. Excellent for hydrofoils | High strength, excellent for hydrofoils | High strength, excellent for hydrofoils | Medium strength. Can only be used on small hydrofoils or with relatively thick profiles that reduce performance. |
|
Shape definition for ease of fabrication
|
Limited to shapes that can be fabricated from plate. | Limited to shapes that can be fabricated from plate. | Complete freedom of shape as foils are moulded. | Aluminium can be readily NC machined, so freedom of shape is possible. |
| Damage resistance to impacts with debris | Very high resistance to damage. Good reliability. | Very high resistance to damage. Good reliability. | Susceptible to damage and delamination at leading edge. | Susceptible to local damage at leading edge. |
| Ability to repair | Good. Weld repairs can be done easily. | Poor. Welding requires require a special oxygen free environment. | Poor. Normally needs replacement in case of damage | Good. Welding skills readily available in most places. |
| Reliability | Very high | High but weld defects can be a cause of reliability problems. | High except during impact with debris. | High but is susceptible to fatigue failure over time. |
| Corrosion resistance | Very high. Does need isolation from aluminium to prevent galvanic corrosion. | Excellent. Inert to corrosion. | Excellent. Inert to corrosion. | Good. Similar to aluminium ships. Does require sacrificial anodes or other form of protection. |
| Weight |
Highest. ~2-5% of boat weight |
Low ~1-3% of boat weight |
Lowest ~0.5-2% of boat weight |
Low 1-3% of boat weight |
Fabrication
& Supply
Icarus Marine offers custom fabrication of hydrofoils in stainless Steel, titanium, aluminium or Carbon composite. Our preference is for stainless steel hydrofoils.
All times needed for installation are supplied together with the hydrofoil, including:
- Bolts, washers, nuts etc.
- Backing plates
- Electrical isolation materials for faying surfaces to prevent galvanic action
- Hydraulic/electric Actuators (if applicable)
- Electronic controls (if applicable)
Construction of a stainless-steel hydrofoil with 12m span for a 45m Catamaran. The largest hydrofoil built anywhere in the world in the last 50 years!
6m span hydrofoil in Titanium
Certification
Hydrofoils generally do not need to be class certified for hydrofoil supported vessels as they are considered to be an appendage.
In certain cases ship-owners do request certification of the foils and Icarus Marine has worked with the following classification societies on certification:
- DNV
- RMRS (only classification society with design rules for hydrofoils)
- CCS
Installation
Icarus Marine provides full support for installation of the hydrofoils that includes:
- Positioning and arrangement of hydrofoils on as-built vessels
- Compensation for fabrication tolerances and deviations
- Adjustment during sea trials
Trials
Icarus Marine will normally take part in sea trials and assist the builder and owner to setup the foils optimally for best performance, elimination of hydrofoil “singing” if present and final sign-off with regulatory authorities.
Contact us for further information.