Testing Propeller Guards

Many boat propeller guard tests have been ran over the years. Some by propeller guard manufacturers, some by outboard and stern drive manufacturers, some by legal teams, some by propeller companies, and some by contract for the U.S. Coast Guard.

Tests include simulated log strikes, striking submerged lumber, using go/no go gauges and rubber feet to measure what will fit though the guard, boat steering and handling tests, drag tests, speed reduction tests, fuel consumption tests, running guards through weeded areas, suspending water chimes in test tanks, and many more.

All kinds of things and surrogates have been ran over during propeller guard tests including: large gourds, squash, cabbages,large tubes of sausage, anatomical crash dummies, simulated manatees, human cadaver body parts, goat carcasses, sheep carcasses, dead ferral pigs, ballistic gelatin, a stuntman, and even life size inflatable dolls.

Tests have been performed by propeller guard manufacturers, outboard and stern drive manufacturers, legal teams, boat rental operations, and U.S. Coast Guard contractors.

Several of the tests are “litigation tests” performed by the industry during legal cases to support their position that propeller guards do not work and are unsafe.

Some of these propeller guard tests are documented in videos.

We are beginning to bring much of the propeller guard testing information together in one place. We started by creating an extensive List of Propeller Guard Tests performed by the U.S. Coast Guard, the boating industry, and academia. If you are aware of any documented testing of propeller guards that is not on our list we would appreciate you pointing those prop guard tests out to us. Please be patient with us as we are trying to finish several other projects before getting back on this one.

In addition to our List of Propeller Guard Tests, we also have a few comments below.

U.S. Coast Guard Propeller Guard Tests

In recent years the U.S. Coast Guard has been developing a propeller guard test protocol for use in testing guards. They are developing standardized tests to evaluate performance, boat handling, and human factors. In 2010 they focused on tank testing at the State University of New York at Buffalo in which they suspended chimes constructed of PVC pipe and ballistic gelatin that resembled wind chimes in the circular test tank at CRESE (Center for Research and Education in Special Environments) at SUNY Buffalo.

The status of these tests is typically updated every six months at the USCG Propeller Injury Mitigation Meetings typically held in conjunction with major boat shows.

Pump Jet Tests

  • Safety Evaluation of the Pump Jet Propulsion Assembly for the Military Amphibious Reconnaissance System. U.S. Marine Corps Research, Development, and Acquisition Command. Quantico VA. Prepared by Naval Civil Engineering Laboratory. Port Hueneme CA. 30 Sept. 1992. This copy comes from a 23 June 1995 comments submission from ACT in response to a request for public input from the U.S. Coast Guard. The Coast Guard published it in their online docket for many years. It was removed in 2008 when they moved to a new docket system.The Pump Jet Safety report above is available on our Pump Jet Safety Report page.