Yamaha Possible Coverup of Propeller Guard Documents Exposed

Yamaha Prop Guard Statements

Yamaha Prop Guard Statements

In March 2012 Yamaha announced a new stainless steel propeller guard for outboards on flood rescue boats in the UK and made several statements about how great it was, how well it performed, and even how prop guards were necessary when people were in the water near the boat. About October we became aware of Yamaha’s new propeller guard. In mid October we began posting some materials about it and some of Yamaha’s own statements about their guard.

The boating industry has long defended itself in propeller injury court cases by claiming propeller guards don’t work. Among their objections, the industry claims guards create too much drag, reduce performance (top speed), effect the handling of the boat, are not durable enough, get bent into the propeller, and they create blunt trauma injuries when they strike people.

But Yamaha was making the exact opposite statements about their propeller guard. Yamaha said their guard worked great, minimized drag and performance reduction, improved handling, was strong and durable for use in shallow water, and guards were essential for operating rescue boats near people in the water.

Our mid October 2012 posts echoed several of Yamaha’s own comments.

By early November 2012, everything Yamaha ever said about the propeller guard AND all records of the guard’s existence vanished from their website. We made many attempts to contact Yamaha about why they pulled all of their materials about the propeller guard, but they will not respond. That leaves us to suspect Yamaha erased their statements to protect the boating industry’s long standing legal defense, “Guards don’t work”.

Among the many specific statements made and deleted by Yamaha about their propeller guard were: Read More →

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Research Projects for Senior Design Classes, Masters Thesis Projects, Industrial Design & Other Researchers

Most college students in engineering and design take one or more design project classes, often a Senior Capstone Design Projects Class, in which they work individually or as teams to develop solutions to problems. We are trying to tap this resource and encourage students to consider selecting design projects related to propeller safety. More student design projects would help grow the body of knowledge available to the industry and to boaters. In addition to engineering and design students, we also welcome those from all fields and encourage them to consider projects in this area for their capstone classes. If you or others are interested in a college design class project or capstone project in propeller safety, propeller injury avoidance devices, or related fields, please view the projects listed below and contact us for additional assistance.

Propeller Guard

Propeller Guard

A few Masters and Doctoral students have written thesis and dissertations in this field. We strongly encourage Masters and Doctoral students looking for thesis and dissertation topics to contact us and discuss some of the possibilities available in their specific field of interest, as well as those looking for topics for scientific and technical papers.

We list of several possible boating propeller safety research projects below and will be posting more over time. Read More →

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Ott Defoe, Mercury, & Nitro win Bassmaster Classic 2019

Congratulations to Ott Defoe on his great Bassmaster Classic win Sunday 17 March 2019.

We screen captured the image of him and his family below as they began the parade around the arena from Bassmaster’s live coverage.

Ott Defoe & family in 2019 Bassmaster Classic after his win

Ott Defoe & family in 2019 Bassmaster Classic after his win
Bassmaster image

Congratulations to Nitro to putting their boat in the winners circle and to Mercury Marine for powering this year’s winner.

Ott Defoe in Nitro livewell for his final bag in 2019 Bassmaster Classic, Knoxville Tennessee

Ott Defoe in Nitro livewell for his final bag of the 2019 Bassmaster Classic, Knoxville Tennessee
Bassmaster image

Thanks to all who participated in this great event, anglers, friends, family, fans, and the city of Knoxville Tennessee for providing great facilities and for turning out in record numbers (we heard 153,000 over the weekend).

Mock race between outboard motor manufacturers. Mercury posted on Instagram from the Knoxville Tennessee 2019 Bassmaster Classic

Mock race between outboard motor manufacturers. Mercury posted on Instagram from the Knoxville Tennessee 2019 Bassmaster Classic

We clipped the great photo below from The Leash’s Facebook feed.

Ott Defoe & family clip from The Leash's Facebook feed as he won the 2019 Bassmaster Classic.

Ott Defoe & family clip from The Leash’s Facebook feed as he won the 2019 Bassmaster Classic.

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Log strike impact mapping / charting invention

Our Log strike impact mapping / charting invention disclosure below was posted on 2 March 2019. We will make no changes to the text below the line following this paragraph except to correct misspellings, punctuation, and to update html/computer codes and links. Any updates to the invention will be posted below the invention disclosure.

Log Strike Impact Mapping /Charting Invention


Log Strike – use of the phrase “log strike” in this invention refers to a marine drive (outboard motor, stern drive, inboard, though hull drive / pod drive, of other marine drive) striking anything while going in a forward direction. Objects struck could include logs, rocks, driftwood, dredge pipes, reefs, concrete, floating debris, submerged objects, stumps, etc. Japanese marine drive manufacturers tend to refer to these impacts as driftwood strikes.

Quick Description of This Invention

This invention proposes using technologies similar to those already patented by Suzuki and Brunswick to record log strikes, share that data anonymously, then create crowd sourced maps/ charts of the aggregated impacts. These crowd sourced maps could be printed paper maps as well as displayed on onboard navigational displays or other electronic devices. Read More →

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Mercury patents log strike monitoring system

Brunswick / Mercury Marine was issued U.S. Patent 10,214,271 Systems and Methods for Monitoring Underwater Impacts to Marine Propulsion Devices on 26 February 2019. Steven J. Gonring and Mark D. Curtis are listed as the inventors.

The patent teaches detecting rate of trim (rate of tilt) to determine an impact occurred. If the drive is tilting more rapidly than normal, it may have struck something. Brunswick talks about alerting the operator, turning the drive off during severe impacts, estimating the force of impact from changes in the rate of trim, storing the resulting data, and evaluating the remaining useful life of the drive or signaling the outboard should be serviced. This system is designed to report impacts above a given level. It does not address impacts that break the outboard off the boat, except to suggest that several impacts above a given level could make an outboard more likely to fail in future impacts.

Near the bottom of this post we identify a Suzuki patent in Japan that may create some prior art issues for Brunswick’s / Mercury Marine’s recent patent.

Brunswick log strike monitoring patent - cover page

Brunswick log strike monitoring patent – cover page

Read More →

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Why outboards break off bass boats paper

In our continuing coverage of large outboard motors breaking off and flipping into boats it is obvious that most incidents in recent years involve bass boats.

Some reasons are obvious: bass boats run fast, bass anglers are in a hurry in bass tournaments, and bass hang out in shallow water. However this paper digs much deeper into the issues.

It suggests the convergence of the bass tournament industry, the conditions present in bass tournaments, and boat & outboard motor manufacturers that created modern bass tournaments had the unintended consequence of bringing together conditions necessary for large outboard motors to strike submerged objects, break off, and flip into boats.

Note: this paper is about 5 MB in size and best viewed on a tablet or desktop computer.

Icon to click on to download the paper on why bass boat outboard motors break off more frequently than others

click icon above to view latest pdf version of paper
Note paper is about 5 MB in size

Read More →

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Boat Propeller Injuries: Medical Case Studies paper

Boat Propeller

Boat Propeller

Trauma Monthly published a great paper in July 2017 in which eight European medical professionals in The Netherlands wrote in detail about four specific boat propeller accidents.

The authors provide medical histories of the four individuals injured including color photos of their injuries, how they were treated by paramedics, what happened initially at the hospital, follow up operations, rehabilitation, psychiatric work with them, and numerical evaluations of the percent of recovery they were eventually able to achieve in terms of pain, other symptoms, function in daily living, function in sport/recreation, and quality of life related to their specific injured joints.

In addition, the authors constructed a summary of similar case studies from approximately 20 separate journal articles. The summary includes counts by author on the number of individuals, number of individuals by sex, mean age, activity during which injury occurred (waterskiing, swimming/diving, other), and the number of individuals that fell off and were ran over.

Motorboat Propeller Injuries: A Case Series and Review of the Literature
by: F. Hoexum, E.A.K. Van Delft, G. Van Couwelaar, A.F.W. Van Der Steeg, C.W. Ang, L.G.M. Geeraedts Jr, F.W. Bloemers, and J. Deunk.
Trauma Monthly
July 2017. Vol.22. No.4.

We strongly recommend this article as a good place for medical professionals to start a study of this field, in part because of the extensive bibliography provided. While we did already have all the pure propeller injury studies they cite on our Propeller Safety Bibliography, it will be useful to medical professionals to have these studies on a more manageable list. With no pure propeller studies on their list that were not already listed in our Propeller Safety Bibliography, we suspect they used it to identify at some of these studies. We are always glad to assist such works.

Thanks to the authors and the several facilities involved in putting all this together.

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Propeller Safety Year in Review 2018

A brief review of the major propeller safety events in 2018 including safety meetings, accidents, legal cases, deaths of those involved in the movement, statistics, patents, articles published, public service announcements, anniversaries, regulations, and other related events. Read More →

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Ryan’s Law filed in State of New York

Back in June 2018 Suffolk County, New York voted to require propeller guards on boats used for youth instruction. The law was named for 12 year-old Ryan Weiss, killed by a boat propeller at Long Island’s Centerport Yacht Club in July 2017. Ryan was killed during a training exercise on righting a capsized sailboat.

Centerport Yacht Club RIB involved in the accident
Centerport Yacht Club RIB involved in the accident

Now, in January 2019, with the boating season a few months off Ryan’s family (Kellie & Kevin Weiss) have teamed with newly elected New York State Senator, Jim Gaughran, to introduce a similar bill statewide.

The Weiss family hopes the bill can be passed before this year’s boating season gets underway per WABC-TV ABC channel 7.

The Weiss family and Senator Gaughran speak on Ryan and Ryan’s Law in the WLNY CBS New York video below.

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NYT article on MLF Bass Pro Tour

The New York Times published an epic article on bass tournaments titled, This is the Most Lucrative Moment in History to Catch Bass, on 18 October 2018. The feature article talks extensively about the history and business of bass fishing, The Bass Anglers Sportsman Society (BASS), a Bassmaster Elite tournament at Waddington, New York in August 2018, and the recent formation of a new tournament series, the Bass Pro Tour, under the Major Fishing League (MFL).

Bass Anglers Sportsman Society (BASS) logo
Bass Anglers Sportsman Society (BASS) logo

When the article was written in October 2018, about 70 BASS association pro anglers had moved over from BASS to MFL’s Bass Pro Tour with its “total payout approaching $10 million.”

Among the major names defecting to the new tour are Kevin VanDam, thought by many to be the greatest bass fisherman ever, Edwin Evers, Skeet Reese, Alton Jones, and Brandon Palaniuk. The article says a total of about 70 pros had defected at that time. Since then, MLF’s web site lists several well known anglers joining their ranks including Tommy Biffle, Gary Clouse, Greg Hackney, Randy Howell, Mike Iaconelli, Chris Lane, Bobby Lane, Dean Rojas,

Major League Fishing logo
Major League Fishing logo

The article notes the sport of bass fishing has exploded at the high school and college levels. Over a hundred additional college clubs affiliated with BASS since 2012. Several colleges now offer bass fishing scholarships.

The author says many they spoke with anticipate rough times ahead for the BASS organization, but they expect BASS to pull though due to its grass roots presence and half a million members.

With another major organization for pro anglers, more serious anglers will likely be considering trying to enter the pro ranks.

We suspect this article will be cited for decades into the future as a major turning point in bass tournament fishing at the elite level. We hope both organizations take this opportunity to make sure their anglers are safe on the water and the integrity of the sport continues.

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Barhanovich case settled

Mark Barhanovich

Mark Barhanovich

Mark Barhanovich was killed when his Suzuki outboard motor struck a dredge pipe alleged not to be properly marked on Sunday morning September 16, 2012 off Biloxi Mississippi near Deer Island. The Suzuki outboard broke off, flipped into his boat. Later that morning, Mr. Barhanovich, a widely known and respected local figure, died from his injuries.

Initially, the dredging firm, C.F. Bean, filed Praying to Exoneration from or Limitation of Liability in Federal Court in the Southern District of Mississippi. The document was basically a Jones Act filing asking the court to apply a law in which their liability could be limited to the value of their barge and its contents (a pile of dirt). The court then asked anyone with a claim against Bean to file it by a certain date. Mr. Barhanovich’s widow filed, and the case began.

Over time some other divisions of Bean and Archer Western Contractors, a firm associated with the dredging operation were brought into the case.

Bean then asked the court to bring some third parties into the case,

  • Suzuki of Japan
  • Suzuki of America – later dismissed because they had filed bankruptcy after the accident
  • Bob’s Machine, manufacturer of the jack plat on the vessel, later dismissed because the jack plate was found to not have played a factor in the accident

Mark Barhanovich's center console fishing boat. Photo from Edward Fritsch expert witness report

Mark Barhanovich’s center console fishing boat.
Photo from Edward Fritsch expert witness report

Mr. Barhanovich’s survivors did not want to allow more parties into the case. They wanted to keep the focus on the dredging operation not properly marking the pipe. The family apparently felt that allowing more players into the case would muddy up the water prolonging the case and make it more complex.

Eventually, Bean and Archer reached a settlement with the Barhanovich family.

Then Bean tried to recover some of their losses from Suzuki of Japan.

All parties involved announced a settlement in a court filing dated 30 November 2018.

The actual case was listed as:

C.F. BEAN, L.L.C.,

Civil No. 1:3cv77-HSO-RHW

We wrote several articles on the case as it progressed through the system. Those articles can be found by clicking on “Barhanovich” in the tag cloud to the right of this article.

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Kickup bracket with jack plate patent application

David Vance Jr. filed a patent application for a jack plate integrated with a kickup bracket. The kickup portion of the assembly is chained to prevent over rotation of the outboard when a submerged object is struck. The patent application was published 22 November 2018. Mr. Vance, the inventor, says this design is for faster vessels and shows a hydraulic jack plate integrated with a kickup bracket as seen in Figure 1 below.

Kickup jack plate with tether patent application

Kickup jack plate with tether patent application

The chains basically act as a tether. The patent application refers to the chain (item #108)as a “limiting strap”.

Kickup jack plate patent application Figure 4

Kickup jack plate patent application Figure 4

Item #140 in the images above is the tensioner that allows the jack plate to kickup (swing out and upward) on impact.

CMC is one of several firms currently building kickup brackets for small outboards. Some CMC units include chains to prevent them from totally breaking free of the transom if they strike something fast enough to fail the bracket.

CMC Kickup bracket

CMC Kickup bracket

As we understand it, Mr. Vance has invented a bracket of this nature that can be integrated with a manual or hydraulic jack plate targeting applications with larger motors and faster speeds.

At first thought, it sounds like an approach that could lengthen the time of contact during strikes of a submerged objects by bass boat outboard motors which would reduce peak loads.

The patent itself is a little confusing about its target market. The patent states it is for faster boats, then says for those in excess of 10 miles per hour. No mention is made of the hydraulic log strike system on large outboard motors or of any interaction between this invention and those systems.

Tiller steering is mentioned at least once in the patent. Thats leads us to speculate they are targeting smaller, but not very small outboards. Such as maybe 25 to 50 horsepower?

We do not recall ever seeing “factory” jackplates on outboards that small, perhaps due to the cost of hydraulic jack plates and to the challenges of bolting smaller outboards to the transom vs. clamping them to the transom?

If in fact the inventor is talking about bass boat outboards, an application where jack plates are frequently used, bass boats already have hydraulic log strike systems. Plus if you added additional trim to the unit by allowing it to kickup, you might smash their large cowl against the rear deck due to minimal clearance already.

We look forward to learning a more about the inventor’s actual intentions if the patent is issued and are happy to see another concept added to those than can prevent outboard motors from breaking off and flipping into the boat.

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