Boating Tips

Prop Guard Provides Protection

The red prop guard is for engines up to 100 hp and the boat can’t run faster than 25 mph.

Experienced boaters know that things happen fast. A typical recreational propeller can travel from head to toe on a person in the water in less than one tenth of a second. Proponents say that propeller guards add a potential margin of safety for boats operated around children, sailors, and swimmers. In a typical year, according to the United States Coast Guard’s annual recreational boating accident statistics, there were 181 propeller accidents, 187 propeller injuries, and 19 propeller fatalities.

Recommended Equipment

Gowrie Group, managers of The Burgee Insurance Program, recommends that propeller guards be considered for all outboard motors used around small boat sailors, children, and swimmers. In many cases this includes boats used for teaching junior sailing, running small boat regattas, and supporting recreational watersports (skiing, tubing, swimming, etc). Propeller guards are typically constructed of polypropylene, and can be affixed to an outboard motor using bolts

Dave Eickmeyer, an advocate for propeller guards from Australia recently said, “The kids are being taught to capsize boats and they love being in the water. You starting thinking to yourself, just one little mistake of the coach or support boat driver believing he is doing the right thing by reversing in or coming in close to a kid and that kid not anticipating, ends up with a hand or a foot or a body into the propeller.” He acknowledges that there can be a decline in top speed when a propeller guard is used, but sailing and crew coaches rarely run at top speed.

Sailing classes usually have a coach’s boat following and a prop guard could be a good idea in this application.

Sail Newport has a fleet of 22 powerboats ranging from 13’ Boston Whalers to 24’ rigid hulled inflatables with engines from 15 hp to 90 hp. The organization is considering standards and regulations for implementing propeller guards. The Olympics has required guards on all coach boats, media boats and official’s vessels. The U.S. Coast Guard reportedly requires propeller driven and fast rescue boats to have propeller guards and many SOLAS tenders used to serve mega yachts are being manufactured with propeller guards.

Clamp Twice, Drill Once

Prop Guard is a plastic, injection-molded cage that covers a propeller on an outboard or sterndrive. It’s designed to surround a propeller like a nozzle and move the water with a controlled directional force. It has no moving parts and attaches with a clamp system and bolts. It comes in two pieces and connects like a clam shell and the skeg of an outboard or sterndrive.

Prop Guard comes with an installation guide and the manufacturer recommends installing it with the Grip Clamps before drilling any holes. For some applications, shimming with nylon washers may be required for proper clearance. The closer the prop blades are to the Prop Guard rings, the less drag is created. The propeller diameter may need to be altered to minimize drag and the engine or drive will need to be trimmed to a setting of optimal performance.

The boat that we saw the Prop Guard is used as a chase craft for Optimist Pram sailboats used by kids.

Five Sizes

Prop Guard comes in five sizes and each is easily identified by its color. The 9” (22.86 cm), 11” (27.94 cm)  13” (33.02 cm) and 14” (35.56 cm) models don’t work with Big Foot or High Thrust outboards in their hp designation. The user would need to move up to the next size. Additionally, Prop Guard is not to be used in applications that exceed 25 mph. The sizes are as follows:

  • 9” (22.86 cm) comes in safety yellow for 9.9 hp up to 20 hp and up to an 8.5” (21.59 cm) diameter prop.
  • 11” (27.94 cm) comes in safety orange for 25 hp to 35 hp and fits up to a 10.5” (26.67 cm) diameter prop.
  • 13” (33.02 cm) comes in safety blue for 40 hp to 65 hp and fits up to a 12.5” (31.75 cm) diameter prop.
  • 14” (35.56 cm) comes in safety red for 70 hp to 100 hp and fits up to a 13.5” (34.29 cm) diameter prop.
  • 16” (40.64 cm) comes in black for 110 hp to 350 hp and fits up to a 15.5” (39.37 cm) diameter prop.

Defender Industries carries a complete line of propeller guards. To find one for your boat, click below.