Not all propellers are created equal. In this interview, Hashim Marzuq, our Marine Propulsion Solutions Application and Installation Team leader, explains how the Three60 Pod 650’s largest-in-class propellers improve efficiency and give yachters better control compared to other similar-class yacht propulsion systems.

Q: What’s the biggest differentiator between the Three60 Pod 650 and the other pods?

A: There are several, but the one that’s probably most noticeable to the average boater is that the Three60 Pod 650 gives you more confidence when maneuvering at very low speed. The Twin Disc® QuickShift™ transmission system built into the Pod is a big reason for that, but the propellers also play a huge role.

Q: How so?

A: The Three60 Pod 650 propellers have a larger diameter and more blade area so they get better “grip” in the water, whereas smaller propellers receiving similar engine torque don’t generate as much thrust and sometimes struggle to push the yacht. The Three60 Pod 650 propellers generate more thrust without having to turn as fast. So if you’re docking in a strong current or a gusty wind, the propellers, combined with the QuickShift™ transmission technology, enable the boat to move smoothly into the dock instead of slipping away from it.

Q: Sounds like the propellers are more efficient, too. Was efficiency a primary concern when designing the Three60 Pod 650?

A: Absolutely. For example, if you look at a conventional shaftline propulsion system, you’ll see that the propeller shaft is at an angle sloping downward toward the stern of the yacht. This causes the propellers to generate vertical thrust, which does not help with speed and fuel consumption. The Three60 Pod 650 propulsor and propellers are parallel to the surface of the water, resulting in maximum horizontal thrust generation and faster speeds. And thanks to the compact “below the waterline” design, the Three60 Pod 650 has less surface area than conventional shaftline propulsion systems, resulting in less friction or drag. This allows the yacht to more efficiently use the power and torque being generated by the engines, which means better acceleration, better top-end speed and better overall fuel consumption.

Q: Speaking of propulsors, I noticed that the Three60 Pod 650’s is different in shape than other pods of a similar class. Why is that?

A: As we were designing the system, we were looking for ways to improve efficiency even more. We found that by not routing the exhaust through the Pod we were able to give the lower portion of the propulsor (or “torpedo”) the shape of a submarine, which reduces friction or drag and creates smooth water flow into the propellers. Overall this design results in improved efficiency, which again translates to better acceleration, better top-end speed and better overall fuel consumption. .

Q: This is pretty technical. But what does it all mean for boaters?

A: It’s one thing to talk about it, but to really understand you have to experience it for yourself. It’s all about a getting better low speed control, getting up on plane quicker and going faster. Burning less fuel certainly doesn’t hurt, either.