How does it keep us safe?

There are no “minor” propeller accidents. Installation of the Prop Guard® on all propellers would greatly reduce prop blade injuries to humans and marine life. The added thrust also allows for better handling control of the vessel. The Coast Guard, life guards and military vessels are preparing to order Prop Guards® because of the greater propeller safety factor and increased vessel control that they can achieve. In a statement from the celebrated Philadelphia court case of Fitzpatrick vs. Madonna & Outboard Marine corporation, Dr. Robert Taggart states that, “the

Schultz nozzle is a basis of a near optimum additional device to provide protection from outboard motor propellers.” Prop Guard® combines the majority of the recommended features into a structurally and hydrodynamically sound

design. Current Federal and State lobbying groups predict a mandatory propeller guard law to be mandated in the very near future. Florida predicts the prop protection law could be passed in the near future to protect the manatees and humans.  Marine insurers are offering premium reductions for policy holders who install safety devices on their vessels now, with further incentives for propeller guards coming.


What is a Prop Guard®?

Prop Guard® is the next patent generation of propeller protection from the noted engineer and inventor Wilderich Schultz. Mr. Schultz has spent his life creating products that improved safety and performance for many aircraft and marine products. Mr. Schultz’s father invented the first propeller nozzle guard, the “Kort Nozzle” for canal and river boats in the early 1930’s. Mr. Schultz took this well proven product and used present technology and hydrodynamic principals to adapt it to the needs of today’s boating industry. Now with the joint engineering and design modifications between Mr. Schultz and Mr. Morrell, the new Prop Guard®. Prop Guard® is a two piece plastic injection molded cage that will completely cover the propeller. The Prop Guard® is attached by a specially designed clamp system and bolts. The Prop Guard’s® two halves are attached like a clam shell to the cavitation plate and the skeg of any outboard or stern drive motor. The easy installation can be accomplished by anyone with simple tools in about 20 minutes.


​Will installing a Prop Guard slow my boat or increase fuel consumption? 

NO! it will improve handling and efficiency. Optimum performance of any vessel is dependent upon the design match between the type of engine, its propulsion system and the type of hull. The delicate balance can easily be upset with an under powered or over powered engine. Even a perfectly well designed propeller may perform miserably if that propeller is placed behind an oversized or overloaded hull. Any problem with these elements can result in poor performance and handling for a vessel.  However, Prop Guard® , even with a technically unbalanced craft can increase the thrust of the propeller. The loss of kinetic energy due to rotational flow in the water downstream of the propeller can be partially recovered by the guide vanes of the Prop Guard® as it creates a counter rotation vortex, reducing the torque effect of the rotating propeller. The hydrofoil nozzle configuration of the Prop Guard® creates forward thrust, which overcomes its own drag and also provides an effective trim without drag. Nozzle propellers produce more thrust than open propellers as the nozzle produces greater dynamic lift for the boat and permits it

to achieve faster acceleration and planing. Prop Guard® eliminates the need for existing or additional drag producing trim devices. In a steep turn, boats tend to turn on their center of gravity and the propeller loses its bite in the water creating uncontrolled rev-ups, as the stern of a boat and the prop moves tangential to the center of gravity of the boat. This is eliminated as the greater lateral area of the nozzle produces a larger effective rudder area. Prop Guard® increases the thrust significantly to overcome handling problems Check out performance test results here.


Installation can be done your self or you can have Safe Waters install it


​Contact us for prices

Keep your family and friends safe, buy a Prop Guard from Safe Waters

631 935 2969

Huntington, NY, USA

Safe Waters




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