How Lift Control Works

“Lift Control,” a key feature of SperryMarine’s innovative and patented fin stabilisation system, is made possible by mounting displacement transducers within the fin shaft. The transducers produce an electrical signal proportional to the lift force generated by the angle of attack of the fin tolocal water stream direction. This lift signalis compared with the instantaneous value of lift required for roll stabilisation. The difference is used to drive each fin until it achieves the desired lift, thereby automatically compensating for variations on the local water stream direction. The angle of the fin will change as needed until the desired lift is being achieved even thoughthe local water stream direction iscontinuously changing.“Lift Control” prevents the fin from beingdriven at times into the Cavitation Zone and at other times from producing a shortfall in lift. The lift forces required for stabilisation are more faithfully produced, giving an improved stabilisation efficiency.

Lift Control Advantages

Stabiliser systems using “Lift Control” produce the demanded peak lifts when required without operating in the cavitation region.Stabiliser systems without “Lift Control” cannot maintainthe required peak lifts because of the fluctuating conditions within the cavitation region.Sperry Marine’s “Lift Control” produces maximum finefficiency not available from any other stabiliser system.

Cavitation Bubbles

Cavitation is real and Sperry Marine understands the dynamics that cause it. The GYROFINStabiliser is the only system thatavoids cavitation thereby, providing improved stabilisation efficiency, less vibration and smoother operation. In the above illustrations we show examples of the conditions at a stabiliser fin with and without “Lift Control.”