The propeller design and material have an impact on the speed of the yacht. That is why it is important to choose the right shape and geometry as well as the size and material of your propeller, to fit your needs and sailing habits. By choosing the right propeller you will not only enhance your yacht performance but also save a lot of money by minimizing the damage to your propeller and lower unit.
In the past, yacht propellers used to be made of bronze alloy. Though it is occasionally used nowadays, the material is not resistant to corrosion, and it is very heavy and brittle. Stainless steel or titanium propellers are a much better choice.
There are advantages and disadvantages to different propeller types, so we have decided to share tips on how to choose the best material for your yacht propeller.
Stainless steel, or inox (from a French word for inoxidizable), is a steel alloy extremely resistant to corrosion and staining. No corrosion damage gives it the upper hand over the other propeller materials.
The durability of a stainless steel propeller is one of the main advantages it has over other materials, while corrosion resistance is a huge plus. This type of propeller could potentially last forever.
The performance is improved due to less flexing of the blades, making the yacht go up to 5 MPH faster in comparison to the one with an aluminum propeller at top-end and 3 MPH at cruising speed.
The strength of stainless steel may be problematic as the blades will not bend if you hit something hard, and the force will get transmitted to the lower unit, potentially causing huge (financial) damage.
If your sailing route carries any risks of hitting something hard, it may be cheaper to get a different type of propeller, which may be easier to deform but will not cause damage to other parts of your yacht.
Aluminum is a soft and very lightweight metal. Propellers made of aluminum guarantee better performance and durability and are made in almost every size and shape you can imagine. It is no wonder why they are most popular among yachting enthusiasts.
The main advantage of the aluminum propeller is the low price. You could afford as much as 2-3 aluminum propellers for the price of a single stainless steel one.
Additionally, there is a huge variety of options when choosing an aluminum propeller, and no matter the type of yacht you have, you can be almost certain you will find the right propeller size and shape.
Aluminum can get easily damaged upon physical contact with tiny rocks or even muddy bottoms. Depending on your usual routes, you should think twice before opting for an aluminum propeller.
Titanium is a material resistant to corrosion, with high strength and low density. It is corrosion resistant and flexible, and probably the best choice for your yacht.
Due to an excellent strength-to-weight ratio and seawater corrosion resistance, a titanium propeller is a great choice for your yacht. Good titanium flexibility can absorb the force from hitting other objects, and the blades will not get deformed.
Titanium tends to be generally more expensive than other materials, due to its rarity as well as casting difficulties.
Now that you have all the information about the positive and negative aspects of all propeller materials, you should consider where and how you use your boat; what type of bottom are you sailing at, and whether there is a risk of hitting a hard object.
These factors should be able to help you figure out which propeller will guarantee the best performance based on your personal needs.