Gyro vs Fins – What’s the Difference?

By July 18, 2017Whitepapers

Both are stabilizing mechanisms, but installing a gyro brings with it a host of benefits. Gyros offer reduced drag and higher hull efficiency, and so, on most yacht installations, selecting a gyro over zero speed fins will result in higher speed, increased range, and fuel savings.

Gyros are Safe for Swimmers

Many Captains will not run zero speed fins when guests are swimming in the vicinity of the yacht for safety reasons. This understandable and responsible, however this compromise between the comfort of those onboard, and swimmers is not required with a gyro installation as there are no appendages in the water.

Reduced Drag, Higher Hull Efficiency

On most yacht installations, selecting a gyro over zero speed fins will result in Higher Speed, Increased Range, and Fuel Savings. The trade-off is between the increase in mass between a fin installation and a gyro. The increased mass does represent a hull drag cost, however when compared to the drag of inefficient low aspect ratio zero speed fins (especially if they are actually working), a significant net reduction in drag is achieved.

No Risk of Grounding Damage

We have all experienced or heard stories of stabilizing fins being damaged by collision with floating debris, or grounding. This usually results in time consuming and expensive dry-docking for repair of replacement. This is simply not possible with a gyrostabilizer located inside the hull.

No Fouling with Nets or Cables

The risk of fouling fishing nets, long lines, buoy anchors, or cables is removed completely with a gyrostabilizer located inside the hull.

No Equipment Outside of the Engine Room

By locating the gyrostabilizer(s) in the engine room, noise levels are reduced as compared to fins (most important at night), and there is no requirement for technical personnel to enter the owner’s spaces for operational or maintenance tasks related to fins.

No Dry-Docking for Maintenance, Ever

Dry-docking is a hectic and crammed period, with many systems requiring attention. A VEEM Gyro can be fully maintained (including major over-haul) within the vessel. So, take a few lines off the docking list by selecting a gyro over fins.

Simple Installation – No Need to Run Cables and Piping Through Frame Penetrations

Enough said. Having the gyro delivered as a fully self-contained item of equipment saves a vast amount of time, effort and money coordinating frame penetrations, cable runs and piping runs through the hull.

Gyros Alone Cannot Control Steady List, so Install with Transom Flaps or Interceptors

One characteristic of a gyrostabilizer is that it cannot sustain a stabilizing torque for an extended time (they are great at opposing motion, but when the motion stops, they stop creating torque). This means that steady list angles due to wind heel or induced during turning manoeuvres, cannot be corrected by a gyro acting alone. Fortunately, there is a highly efficient solution to this.

In order to optimise trim (to maximise fuel efficiency, and speed) and to manage list angles, it is recommended that the gyro be installed with either transom flaps or interceptors. By doing so, you get all the comfort and low drag benefits of the gyro (including no ugly appendages prone to damage and fouling), as well as steady state trim and list control. Both trim flaps and interceptors are extremely efficient at controlling steady state running trim and list. Both solutions also maintain clean hull lines free of appendages and their costs.

VEEM can provide integrated control of the gyro(s) and an auto trim/list system. This system provides both auto trim and auto trim management. By allowing the gyro(s) to do the dynamic stabilization work, the transom flaps or interceptors power supply can be compact and efficient. When two pairs of fins are installed on a vessel, they can be used to correct trim and list. However, this detracts from the force available to roll control and is relatively inefficient from a drag perspective.

Want to know more? Take advantage of VEEM’s exceptional pre-sale technical support and find the optimum gyrostabilizer solution to suit your specific requirements.