Propeller Safety Thoughts Prior to June 2011

Propeller Safety & Propeller Injuries – Our Thoughts Prior to June 2011

We captured our thoughts about propeller safety on a page prior to moving to our new format in June 2011. We moved the page capturing our earlier thoughts to this post. Our more recent thoughts are in the blog.

These are just thoughts we have had surrounding propeller injury avoidance in general and related issues. We started logging them here in May 2005. We hope to follow up on some of them as time allows. They are intended to stimulate thought and conversation about potential solutions. Several are just brief thoughts I have had and may not be well thought out. If you have any comments about them or thoughts to add, please contact us.

28 August 2010 – The Case Against Corporate Social Responsibility. The Journal Market Reports. Wall Street Journal. 23 August 2010. Page R1.

The author, Dr. Aneel Karnani, points out the idea that companies will act in the public interest AND profit from it is fundamentally flawed. Companies purely out to make money do improve social welfare by putting more dollars in the pockets of their stockholders. In situations where profits and social welfare are in direct opposition, executives are unlikely to act in the public interest against their shareholders interests.

He points out some situations in which companies have acted for social good such as fast food outlets adding salads, others adding whole grain and low fat foods, auto companies adding more fuel efficient vehicles. He then notes that social forces were not the driving forces, these changes came about because they became profitable to the companies involved.

He analyzes situations in which their is a choice. Often doing what is right means sacrificing profits. If it didn’t, the problem would have been solved a long time ago. Executives are hired to maximize profits. If they stray from that maxim, they will be replaced. Privately owned companies are a different matter. Some elect to reap lower profits in the name of public good.

Karnani says the balance can be struck by regulation. The government has the power to force executives to make the right decision. With regulations in place forcing certain social choices, executives can then make the right decision and not be seen wasting money by the stockholders.

The author notes that industry groups might find ways to influence regulations or even end up benefiting from the regulation at the expense of the general public.

Then he notes watchdogs and advocates can try to influence executives to make the right decisions and convince them them it won’t hurt their bottom line.

Sometimes industries self regulate (self control) but companies are unlikely to act in the public interest at the expense of their shareholders.

“In the end, social responsibility is a financial decision for executives…”

We found this article on social responsibility very compelling when carried over to the propeller safety realm. Many of the statements in the article can be seen reflected in the swirl surrounding the industry’s refusal to pursue the use of propeller safety devices.

18 August 2010 – Further Comments on ROPS per our earlier 30 January 2009 post.

In the early days of ROPS (Roll Over Protection Structure) being proposed, the industry countered saying agricultural tractor frames could not or were not designed to take the loads that would be imparted to them by ROPS during a rollover. Frames are now designed to take those loads and ROPS attachment points are provided. That is parallel to the boating industry claiming marine drives were not designed to take the loads and vibration put on them by propeller guards. Drives could be beefed up where necessary and attachment points for guards could be provided.

We notice SAE (Society of Automotive Engineers) is now working on an “Interactive Smart Standard J1040 ROPS” to shorten time to market and bring to market the most effective ROPS. It will be a computer simulated smart standards that will take text, mathematical formulas, equations, charts, illustrations and tables and turn them into calculations, data lookups and answers to design problems. The project to develop the standard is anticipated to go through 4 phases:

  1. Feasibility phase
  2. Design phase
  3. Prototype phase
  4. Production phase

The industry supports the development of this new standard because they perceive it will provide increased safety for occupants of ROPS equipped machines and reduce their liability.

A similar smart standard might be appropriate for propeller guards. The standard could incorporate CAD, CFD, and a crash program to analyze drag, cavitation, boat handling, crushing when striking solid objects, and other variables much quicker in the design stages before actually building a guard.

Yes, we are aware the USCG has a propeller guard test protocol under development. If they can ever finish it, the next step might be to create a smart standard like the ROPS standard under development.

2 February 2009 – Propeller Guard With Reduced Drag – today we placed an invention we have been working on for over a year in the public domain. This invention exploits the large reduction in drag that occurs when boundary layer flow of water across a circular cylinder (wires or rods used in propeller guards) transitions from laminar to turbulent.

The phenomena allows use of larger diameter rods or other shapes (for increased strength and durability) in forming the cage AND/OR a tighter mesh (reduces the potential for contact with the propeller or entrapment) than previously possible without creating tremendous drag AND/OR attaining higher boat speeds.

Although this invention needs further development, we feel it worthy of further investigation due to the potential significant drag reductions possible. Details were posted on our Propeller Guard With Reduced Drag page.

We also placed two more of our propeller safety inventions in the public domain today. They are posted on our Propeller Safety Technologies page.

One details methods for reducing false signals from a system trying to detect people in the water near a propeller.

The second describes use for high strength fibers, such as Dyneema, in the formation of propeller guard screens.

30 Jan 2009 – Tractor Roll Over Bars Are Similar to Propeller Guards – Back in the mid 1970’s I worked for Charles Machine Works (Ditch Witch Trenchers) during the era rollover protective structure (ROPS) become widely used on construction equipment. I recall some of the early testing. Anyway, U.S. stats on farm tractors about ten years ago show about 125 people killed in rollovers per year and a few times to many times that many injured depending on who you talk to (under reporting issues there too). Those stats place tractor ROPS as least in the same magnitude range as reported prop fatalities.

A ROPS is basically a cage type guard that is used in conjunction with a seat belt. Its purpose is to keep your body from hitting the ground (just like a prop guard tries to keep you from hitting the prop).

We might learn some things from further study of ROPS. I did notice some groups have studied the use of financial incentives to encourage putting them on older tractors (like putting guards on existing boats).

Plus, there are many types of ROPS and tractors (similar to guards and boats). All ROPS will not prevent all rollover fatalities or injuries. A study in Kentucky found something near a three times improvement in liveability of a rollover with a ROPS. Some still died (some of those probably did not have their seat belt on). Some older tractors still do not have ROPS designed for use on them.

Ag safety groups have been screaming about tractor rollover safety and ROPS for decades. Seems like there are lots of similarities between the two situations.

27 Jan 2009 – Being Sued Personally for Prop Injuries – this morning I read the results of a Summit County Colorado case in todays Summit Daily News. The operator of a boat received two years in prison when he pleaded guilty to boating under the influence and criminally negligent homicide in the death of his friend by the propeller of a rental boat. We have seen many cases recently where boat operators are being tried and found guilty for their contribution to the severe injury or death of others by a propeller.

Traditionally, early propeller injury cases tried boat and marine drive manufacturers for not using guards to protect people from the propeller. Now many cases sue the operator for their actions contributing to the accident. We are beginning to wonder if an operator might be sued for not putting a guard or other safety device on their boat? OR if guards and similar devices might be marketed as a way to reduce a boat operator’s exposure to a criminal lawsuit because the propeller portion of the person’s injuries would be avoided or reduced. Yes, obviously boat operators should not be operating under the influence of alcohol and should always operate the boat in a safe manner. We all know that is not always the case for all boat operators at all times. Propeller safety devices could prevent those operators from being in the situation the gentleman in Colorado is in.

23 January 2009 we published a rough draft of our response to USCG’s withdrawal of proposed houseboat propeller safety regulations. It is a lengthy report and we are requesting assistance in editing it for accuracy. The report covers many facets of propeller safety with implications beyond houseboats. We would very much appreciate everybody’s help in editing the report for accuracy.

14 Jan 2009 – Rental boat prop dings – we recently had a conversation with someone who had spoken to a rental boat operation. That renter had problems with smaller boats getting their props dinged by renters. They have to keep inspecting them at rental turnover, and try to get the repair or replacement money out of the renters. Sometimes they cannot recover the money and even if they do, the renter often leaves with a bad experience and never comes back (not just to them but never wants to rent a boat again which is bad for the industry). Plus they have to devote time to repairing, replacing the props. The renter said a propeller safety device that not only protects people, but also significantly reduced prop dings would appeal to them.

Moving/positioning some devices away from being people protectors, and focusing more on protecting propellers might be a good marketing approach for some of the many alternative devices and approaches now coming on the market. Instead of having the break down the industry’s resistance to conventional propeller safety devices (i.e. guards), companies could focus more on the propeller protection market? Its kind of interesting that is where propeller guards started in the first place, they protected propellers.

14 Jan 2009 – Situational Awareness – we first noticed this term some time ago in reference to helicopter blade accidents (typically fatalities of people under the rotor raising their head while the blades are still turning). The U.S. military has studied and promoted situational awareness for those near helicopters in studies like, Helicopter Rotor Blade Injury: A Persistent Safety Hazard in the U.S. Army. by Crowley and Geyer back in 1993. An abstract is on PubMed.

Yesterday I was wandering the Oklahoma State University Library and came across two situational awareness papers in a June 2008 issue of The Journal of Human Factors and Ergonomics Society. One reviewed some of the development in the area and provided a rough definition (Knowing whats going on) and a more formal definition (The perception of the elements in the environment within a volume of time and space, the comprehension of their meaning and the projection of their status in the near future.) It went on to talk of three levels of situational awareness, 1. Perception, 2. Comprehension, and 3. Projection.

This all seems very relevant to propeller accidents involving those in the water near a propeller when the drive is started. Those in the water need a situational awareness of the propeller (perception), to understand it could be rotating (comprehension), and to realize it could pull them in or back over them (projection). The industry is trying to do that with decals and education. It seems like this area might be worth some more study and see how situational awareness has been developed in other areas with some relevance to the boating application (helicopter rotors, light planes, large open fans, industrial mixers, etc).

23 Nov 2008 – Similarities in Prop Guarding and Intelligent Design? Last night I came across a propeller guard legal case proposed as a final exam by Professor David K. DeWolf at Gonzaga in the summer of 2000. The exam and a sample answer were both posted online. As I started to follow his work a little further, I noticed Professor DeWolf has written several legal papers concerning the opportunity to teach Intelligent Design (a creator directed evolution) in public schools and how some consider that teaching Creationism. At any rate, some of his papers address how new ideas and approaches are often rejected by the scientific community. He coauthored Intelligent Design Will Survive Kitzmiller v. Dover which has a lengthy discussion of the acceptance of new ideas and how difficult it is to overcome the bias of existing authorities. While I personally am a creationist, I find his article very interesting while thinking of it in terms of how the boating industry has rejected guarding of propellers, but the Advocates and families of those injured continue to press the issue. Just like evolution, creationism, and intelligent design, prop guarding is an emotional issue, however it is on a much smaller scale as only a small percentage of the country is caught up in it v. millions of people on the fringes of the other debate. Those on both sides of the guarding issue might learn some things by reading Professor DeWolf’s article.

3 Nov 2008 – today we posted our Propeller Safety Device RADAR Plot spreadsheet method of indicating relative performance of several different propeller safety devices against multiple types of propeller accidents on the same chart. It is part of a tool we are continuing to develop to help boaters pick the best devices and approaches for their specific situation.

6 Oct 2008 – An online forum asked some questions about the propeller safety issue in general and I created a large chart titled, Aspects of the Debate Surrounding Propeller Safety Issues as part of my response. We will further develop this chart in the future.

7 July 2008 – Escalating fuel costs are probably reducing most types of boating accidents for 2008. Its possible they might disproportionately reduce propeller accident frequencies as the wilder crowd (higher speeds, erratic, boat paths, alcohol, etc) might be more put off by high fuel cost than average boaters as they probably use more fuel?

Pulling tubes uses quite a bit of fuel. The number of boats pulling tubes as well as how many hours they are tubing may be decreasing as well, reducing the amount of time tubers are at risk to propeller strikes.

Increasing fuel costs may result in safer waters by just reducing activity levels, especially in previously crowded areas.

3 July 2008 – The automotive industry is starting to move on from vision systems to active accident avoidance using visions systems (the car responding to what it sees). Dedicated chips are coming on the scene like Mobileye EyeQ2 from MobileEye that can fuse vision and radar systems. The houseboat industry has yet to seriously look at visual (or other) sensors to detect people near propellers. Its like we are still using tin can phones with a string between them while the automotive industry is moving from landlines to mobile phones.

29 June 2008 – Today’s Los Angeles Times puts forth some thoughts toward how gun manufacturers could reduce gun deaths in the wake of the recent affirmation of the right the bear arms by the U.S. Supreme Court. Their suggestions appear to be quite transferable to propeller deaths and injuries. The editorial/opinion piece, How Gun Makers Can Help Us, by Jeffrey Fagan and Stephen D. Sugarman in the 29 June 2008 Los Angeles Times article proposes instead of trying to force specific legislated actions on gun manufacturers, that Congress establish performance based regulation. Tell them what outcome must be achieved, reduce deaths by guns, let them figure it out. For example, Congress could require a reduction in gun homicides from 12,000 to 7,000 in ten years with interim targets. Individual firms would each have their own targets based on the extent their products are currently used in homicides or Congress could leave it to neutral experts to determine how much reduction is required and how fast it should be achieved. Individual gun manufacturers might choose to add trigger locks, to only work with responsible dealers, to work with local officials to fight gangs and increase youth employment, pull some semi-automatic weapons from the consumer market, cap and trade (like emissions certificate trading) among manufacturers, and other strategies.

Similar approaches could be chosen by boat and drive manufacturers to fight propeller injuries (install guards and interlocks, work with responsible rental operations, campaign for licensing requirements, wearing life jackets, address alcohol issues, etc. Let the manufacturers figure out how to do it. it raises several interesting points.

26 April 2008 – Yesterday while thinking about parallels to houseboat propeller risks to those in the water near the stern swim ladder I came up with an example. Suppose you were sitting in an 8 foot square indoor jacuzzi / hot tub with your back against one wall. A large outboard engine is mounted on the opposite end with its propeller a few feet from your feet. The switch to start the outboard in reverse is outside in the hall about 30 plus from the door to the room with the jacuzzi. A small decal near the switch warns those thinking about throwing the switch to walk down the hall, open the door and look in the room to make sure nobody is in the jacuzzi before they throw the switch and start the outboard in reverse. There is little difference in those two situations, EXCEPT those in the jacuzzi would be more aware of their risk due to seeing the outboard, vs. those in the water behind a houseboat who are often not aware of their proximity to a propeller.

26 April 2008 – Thinking about those who propose education as an alternative to guards and interlocks, I wonder if guns would still be around without safeties (interlocks) and trigger guards (guards). Just like with propellers, it would be very hard to make them safe with education being the only approach. Education works best when used in conjunction with other accident mitigation practices.

26 April 2008 – Industrial dryer similarities – I came across a Wall Street Journal article, “House Panel to Examine Cintas Plants’ Safety Record” 23 April 2008 Pgs. B1 and B2. Cintas operates large industrial laundry washing facilities around the U.S. (wash company uniforms, jeans, shop rags, etc). The article focuses on an accident in Tulsa in which an employee climbed on a moving conveyor and started jumping up and down on a pile of clothes to push them through the door of a huge dryer (conveyors carry the clothes from a large washer to a large dryer). He fell in, the automatic door closed, the pilot light ignited, and another employee heard a loud thudding noise over 20 minutes later. He was found dead in a pile of jeans. The entire process was caught on surveillance video.

Dryers with conveyor feeds are quite similar to propeller hazards (rotating dryer represents the propeller and conveyor represents the current, inflow to the prop). They use similar protection approaches. Education (Cintas says every employee at the Tulsa facility including the receptionist was trained to never get on an energized conveyor). However, surveillance video showed other employees engaging in similar activities to the deceased gentleman at least 34 times in the two weeks prior to the fatality.

They also use “presence sensor guarding” which is supposed to shut off a shuttle (conveyor) if it encounters a person as it moves along its track. These sensors were in use in Tulsa, but did not prevent people from jumping on the machine while it was operating.

In addition, previously every employee that entered the washing area at one of their facilities in Washington carried a safety switch that could be used to shut off machinery in case of emergency. After taking over the facility, Cintas quit using those switches as well as dropped a rule previously requiring two people to be the washroom at one time.

We had previously looked at parallels with industrial mixers. Industrial washers and dryers are essentially big mixers and harbor similar dangers. Those trying to reduce propeller injuries might find it useful to study these similar dangers and how they have or have not been effectively addressed.

16 March 2008 – The American Automobile Association (AAA) recently released a study, “Crashes vs. Congestion: What’s the Cost to Society?” Cambridge Systematics. March 2008. They point out crashes happen randomly and only affect a few people each time they do occur. Most Americans think they are good drivers and do not think they will be involved in a crash. AAA whines in several articles about the study about automobile accidents not being on people’s minds due to the same kinds of reasons propeller accidents are not on people’s minds (they happen randomly and only involve a few people at a time). AAA is going to try to raise awareness level, similar to our efforts to raise awareness of propeller injuries. We find it interesting that automobile accidents which happen at frequencies much higher than propeller accidents, still have some of the same problems in awareness levels.

16 March 2008 – I came across a Wall Street Journal article, “Insurers Pressed to Pay More for Prosthesis”, WSJ 11 March 2008 Pgs. D1 and D3. Advances in prosthesis technologies have increased their costs, those costs have been recognized by private health care plans, and many of them are now limiting coverage. Amputees, amputee organizations and prosthetic manufacturers are lobbying state legislatures to mandate coverage. This battle is very important to many propeller victims who have lost limbs and to those who will become propeller victims in the future.

8 Jan 2008 – I spent some time today looking at similarities between propeller backover accidents and vehicular driveway backover accidents of young children. Both often involve visibility issues and can result in very serious injuries or death. Driveway accidents also share under reporting difficulties as most of them are excluded from the typical highway injury databases because they occur on private property. I noticed several groups trying to reduce driveway backovers with a “Spot the Tot” educational program that began in the State of Utah. Details of that program may be of interest to those promoting educational solutions to propeller backover issues. One element of it is a reminder sticker for driver side windows.

21-22 Nov 2007 – We are not alone. Other industries have similar safety issues. We can learn much from them and the techniques they employ. The marine industry has been extremely slow to look outside for help. Among tools and areas that look promising are:

  • Haddon Matrix
  • Fault Trees
  • Detailed On Site Propeller Accident Investigations
  • Followup interviews with those injured
  • Analyzing existing hospital/accident/injury databases for better accident counts (reducing under reporting)
  • Studying the Effectiveness of Warnings on Boaters
  • Active Warning Systems
  • Converting and Adapting good academic and hardware work from other fields similar to this one, especially from agricultural safety applications (Tractor PTO shafts, Grain Augers, Auto Deployable ROPS (deploy a guard), Ultrasonic and Microwave Human Presence Sensing in Agriculture, etc.), swimming pools (human detection and drowning detection) and military in water/under water surveillance efforts
  • Utilizing the propeller cut analysis techniques being carried out on manatees and right whales that looks very applicable to humans
  • Testing and analyzing the idea of allowing the drive to swing up freely when going forward to minimize blunt trauma (impact limited to drive momentum plus drive propulsion force, NOT boat momentum)
  • Studying propeller inflow patterns at startup (danger zones)
  • Studying the vaccination with a perceived vulnerability to propeller strike concept as related to being safer after major local accident.

We would especially encourage industry organizations to become involved in pursuing these tools and ideas. If any organizations, companies, grad students or others would like to pursue one of these topics, please contact us and we will try to help out a bit. We would also welcome any group that would like to fund some of our efforts in these areas.

29 Oct 2007 – Balanced Scorecard for Propeller Injury Avoidance Product Design – several years ago, some Harvard professors started promoting a “Balanced Scorecard” for companies as a way of putting their vision and strategy into a set of performance measures. We have since seen a few groups trying to adopt the same basic approach to address other complex problems. This morning I came across an article in Consulting -Specifying Engineer, October 2007 titled “Going Green in Data Centers” (pgs 42-46). Designing Server Farms to hold thousands of computers to use the minimal amount of energy, have minimal impact on the environment, have low life cycle costs, and provide as much uptime as possible is a very complex task. The article described how the Balanced Scorecard approach is being applied to Data Center design. I began thinking about how it could be applied to Propeller Injury Avoidance Device Design. To us, it appears like the four areas to be “balanced” are:

  1. Life Cycle Costs (product cost, installation cost, training costs, maintenance costs, operational costs, etc LESS any savings from using the product).
  2. Effectiveness (how well does it work, how many accidents will it prevent, will people still be hurt in some way, how many types/scenarios of propeller accidents will it prevent, etc)
  3. Industry Impact (how easily is it accepted into the current way of doing things and how much does it impact those in the business, do they have to make a lot of changes, will they encounter problems, how does it impact boats already in the field, does it require redesign of existing boats or drives, any product liability implications to past or present, etc).
  4. Boating Experience Impact (will it change the boaters experience, will they have to do several things to make it work, can they still accomplish what they want to, is boating still fun, is the product “seamless”, etc.)

Those designing new products in this area or improving existing products would do well to think about their product from this point of view and how it stacks up against other products in the arena.

We hope to further develop the Balanced Scorecard approach to designing and evaluating Propeller Injury Avoidance Devices as part of the materials we are preparing to aid boaters in evaluating their risk and selecting the best category of devices for their particular situation.

24 Oct 2007 – “NASA Airplane Safety Report Stalled” ABC World News (23 Oct 2004) and many other outlets are reporting NASA surveyed 24,000 commercial and general aviation pilots over four years through 2005 to collect information on safety related incidents. That data apparently shows a much higher incident rate than FAA reported incidents. Some suggest the FAA is suppressing the data as they have been charged with reducing incident counts. Its starting to sound pretty similar to the propeller situation. The U.S. Coast Guard has been charged to reduce the number of reported boating accidents. That gives them gives them an incentive to NOT look hard for them. If your not buying into this line of logic, you might want to recall they (USCG and FAA) were under the same U.S. Department of Transportation or many years. The Current USCG Office of Boating Safety Strategic Plan similarly sets targets for reducing the number of reported accidents (see pgs 2 and 3 – actually numbered pgs 1 and 2) which is a great goal, but fails to address the problem of under reporting and provides no incentive to hunt for those not reported..

22 Oct 2007 – today we launched the High Profile Propeller Accidents page, a list of accidents from the U.S. and around the world that received significant media attention or otherwise impacted the industry since recreational power boating came on the scene. The accidents are listed in order of occurrence, which just prompted us to also think about creating a time line chart from the list to indicate what has been going on and to impress upon our minds that it is not going to stop as long as we keep doing things the way we are.

26 Aug 2007 – Floating Trim Cylinders v. Manatees – a few days ago I posted some information on two Brunswick trim cylinder patents from the 1970’s on our technologies page (see 17 August 2007 entry on our Propeller Safety Technologies page). They were designed to float over obstructions hit at slower speeds (primarily to prevent the boat from stopping so fast that people were ejected). When I posted them I was thinking about how they might be used to protect cage type guards from impact damage or possibly even reduce blunt trauma to people. Today I came across a Sept. 2006 Manatee Mortality article in Journal of Zoo and Wildlife Magazine and had a moment of inspiration. The 1970’s floating trim cylinder patents might well reduce blunt trauma to manatees. I will contact one of the manatee people I have visited with before and see what he thinks. I notice he is also one of the authors listed on the paper. The Brunswick patents are U.S. Patent 3,999,502 and U.S. Patent 4,050,359.

8 August 2007 – Follow up on our 11 July and 27 July comments on how the media can vaccinate area boaters with vigilance for their own safety – Over the past weekend I traveled to a family funeral and heard several comments from other travelers about their concerns for the safety of bridges they had just passed over in the aftermath of the Minneapolis bridge disaster on August 2nd. They had certainly been vaccinated with an awareness and concern, even though the safety of bridges is beyond their ability to control as individuals (yes they could get politically involved, etc. but they cant just make minor changes to their vehicle and drive safer to get safer bridges).

Earlier (16 March 2007) I wrote on how the boating media and some regions of the country seem to be avoiding reporting on propeller accidents : Propeller Deaths and Injuries: Another Inconvenient Truth. They gloss over, do not cover, or under report the problem to sell more boats and keep more visitors coming to their recreational areas bringing in more dollars. Thinking about this in terms of our “vaccination” concept, they may well be creating more accidents. Their lack of reporting these accidents in the media misses the opportunity to “vaccinate” boaters with a “perceived vulnerability” to propeller injuries, missing the opportunity to encourage perhaps thousands of them to be more vigilant. Boaters do not read about the accident and then later have one of their own which is also not reported in the media, then someone else has one, etc. In their efforts to protect themselves, they are actually contributing to more accidents and missing an opportunity to at least temporarily break the chain.

Today I noticed:

The Effect of Risk Communication on Risk Perceptions: The Significance of Individual Differences
Journal of the National Cancer Institute Monographs
Vol. 1999. Number 25. Pages 94-100.

It tries to shed some light on how some individuals may be influenced by health/safety discussions in the media. It focuses on health risks, but many concepts raised there may transfer over to our “vaccination” discussion.

As long as we are on this topic, Boat & Motor Dealer has yet to respond in print to our calling to their attention over 9 months ago that the actual number of people killed or injured by propellers according to U.S. Coast Guard reported recreational boat propeller accidents is actually several times the statistics the magazine attributed to the Coast Guard data in a Sept/Oct 2006 article. Their failure to respond to our many requests may actually be resulting in more people being injured and killed. Their magazine goes to boat dealers and others (many of whom boat themselves) who may be passing on their incorrect statistics to customers and other boaters giving them an incorrect picture of their safety.

8 August 2007 – I saw a couple magazine articles yesterday with titles that made me reflect on the propeller issue. A recent Popular Mechanics (probably August 2007) in a waiting room has a section on Ten Aviation Accidents That Changed The Safety of Flight (I do not remember the exact title). For a few months I have been throwing my thoughts at a somewhat similar article for propeller injuries (trying to identify accidents that resulted in people becoming propeller safety advocates, became pivotal court cases, inspired people to design propeller injury avoidance devices, etc.) Its a shame we cant title it Ten propeller accidents that changed the safety of boating, but the industry has yet to respond.

Newsweek August 13th issue cover story is titled, “Global Warming Is Hoax” with an asterisk beside it. At the bottom of the page, an asterisks appears with the following text “or so claim well-funded naysayers who still reject the overwhelming evidence of climate change: Inside the Denial Machine”. The actual article is titled “The Truth About Denial” and on pages 20-29. Many propeller safety advocates can probably see parallels between the response of the boating industry to that of those denying Global Warming.

27 July 2007 – Follow Up to our July 11th comments on how local accidents vaccinate area boaters with greater awareness of specific risks and with a desire to prevent similar accidents from happening to them. Locally, there has just been such a response to an accident in another recreational activity. Sunday 22 July, an area minor league baseball team, the Tulsa Drillers, had a 35 year old first base coach, Mike Coolbaugh, struck in the head and killed by a line drive foul ball (later reports say he was struck in the neck behind his left ear which ruptured an artery). This accident has been covered very strongly by the local media (see report from KOCO5 as an example). This morning I heard Tom Dirato, a local radio sportscaster with a lot of experience at covering baseball, talking about some of the issues involved (coaches not staying in the designated coaching boxes, aluminum bats being so quick there is no time to get out of the way, coaches letting their guard down, he mentioned third base coaches often move close towards home than they are supposed to in order to better see the angle of a player possibly coming from second exposing themselves even worse and umpires no longer enforcing them to stay in the box, he also had some comments from other base coaches). Right now our region is vaccinated against this type of accident and we would expect base coaches (at the college and pro level) to be very alert for a while, but to drop back to their old ways over time. Base Coaches being hit by foul balls has some similarities to some propeller accidents (happen so fast is hard for person to avoid contact, requires constant vigilance, need to be where you should be and not where you should not, relatively rarely reported at a given locale, near misses are not reported, both involve recreation, coaches not taking all the precautions vs. boat operators not wearing a lanyard kill switch, the Tulsa driller accident took place in the top of the 9th inning – maybe like boater fatigue, young people involved, the basic activity equipment is changing resulting in increased risk (aluminum bats vs. tubing) etc.)

Individual reported propeller accidents AND individual reported baseball base coach accidents tend to get more press than individual industrial accidents or individual automobile accidents. Readers and viewers probably have a “sense” there is some risk involved with being in a car or working in a factory, but are shocked when they find their is risk with recreational activities, especially life and death type risks. Boaters reading about local propeller accidents are probably more likely to change their behavior than drivers reading about local automobile accidents. Similarly, many base coaches in this area are probably on high alert. How much it caught their attention can be seen from an article, “Extra Precautions Discussed in Wake of Coolbaugh’s Death” reported by ESPN 24 July 2007.

On a more personal note, about thirty years ago I personally witnessed an accident at a baseball game in a very small town that took the life of one of the young men playing the game. I am still very vaccinated with a “perceived vulnerability” to that particular type of baseball accident and have told many of it through the years, including some who played for me when I coached summer league softball. Yes, these accidents can vaccinate people, but its a shame we can’t vaccinate them before they occur.

16 July 2007 – Reporting Propeller Accidents – we were gathering some info to encourage people involved in boating accidents to report their accident to their state and to the USCG and noticed the USCG Boating Accident Reporting Site provides a link near the bottom for “If you need assistance in locating where to call within each state or territory, or reporting an accident, call the Coast Guard Hotline.” But, if you follow the link to the Coast Guard Hotline you read that “Effective October 1, 2006, the Coast Guard Infoline telephone service will no longer be offered.” And we wonder why boating accidents are under reported?.

14-15 July 2007 – This post is a brief summary of some of our current activities and projects, along with a request for some help. If anybody has any comments on these projects or has some related ideas, please contact us.

  1. Posting more in-depth information on a “hinged” propeller guard we first mentioned here back on 13 Oct 2006. We have since refined the idea considerably and feel it is really showing some promise, especially for houseboats and pontoon boats.2 August 2007 follow up – in essence we now leave ALL the structure on the drive and just flap a circular cover with a tab on it. We are in process of trying to draw it up and post it but are struggling to find time.
  2. A tool for boaters to evaluate the risk of propeller injury to those on and around their boat, plus a tool to help them sort through the available propeller injury avoidance devices, and educational materials to reduce their risk of propeller accidents.
  3. Further discussion of how local accidents “vaccinate” area boaters with a “perceived vulnerability” to propeller injuries and push them toward being safer boaters, at least in the short term. We are gathering research on the impacts
    of other types of accidents on behavior changes and resulting safety records of individuals.
  4. We are still trying to get Boat & Motor magazine to print the correct USCG statistics instead of the significantly lower numbers they printed by error and refuse to change.
  5. Creating a huge “Fault Tree” that uses logic “ANDs”, “ORs”, etc. to show how and where various propeller injury avoidance devices try to break the accident chain and which accident chains they can and cannot break.
  6. Following up on some propeller flow and wake studies that appear to open up a concept nobody seems to have looked into before. More info on this later.
  7. We are in process of trying to formulate a response to a recent press release from BoatUS on boating safety we have some real problems with. They improperly use statistics to try to compare safety in a boat to safety in a bath tub / shower.
  8. Posting links to past propeller accidents from Missouri’s online boating accident database to our media coverage page.
  9. We are studying the broader topic of communication and health behavior looking for some tools that might be useful in encouraging people to be safer around propellers.
  10. Similarly we are in a swirl without a particular vision now while studying survivor advocacy, and how change has been brought about in other industries. We are not exactly sure where it is heading but it feels promising.
  11. Increase coverage of military applications of propeller guards and other propeller safety devices on small craft worldwide.
  12. Increased coverage of fire, rescue and patrol boat applications of propeller safety devices.
  13. Increased coverage of houseboats with propeller guards and related propeller injury avoidance devices.
  14. Cover the U.S. Coast Guard propeller guard testing coming up in late August or so.
  15. Looking forward to analyzing the 2006 USCG boating accident database upon its release.
  16. Launching a quarterly newsletter by the end of the year.
  17. We will be launching a new portal hopefully by start of the school year that we think will be vital in encouraging college students to do design and research projects in the area of propeller safety.

The projects above will certainly keep us busy a while, along with logging accidents covered by the media, logging new patents, following related news and trying to encourage communication between the players proposing solutions.

We initially posted the start of our “Help Wanted” list here, but we moved it to its own page on 16 July 2007. You can view our list of requests for assistance at Help Us.

14 July 2007 In coverage of the recent serious multi-victim propeller accident near Old Saybrook CT, I noticed an individual wrote into a newspaper suggesting boats have sensors similar to those used to deploy airbags in cars. The ones in boats would stop the propeller the moment the boat collided with another boat (or anything else) and prevent “run over another boat and the people in it with my propeller still turning” type of accidents.

13 July 2007 We came across, an Advocacy site for helping young people deal with cancer. It appears to be very well done and might serve as a model for a similar site for young people dealing with propeller strikes or one for anybody dealing with propeller strikes.

11 July 2007 Local propeller accidents are like vaccinations – Do you recall the last time someone got hit by a train at a railroad crossing in your community? Typically when someone gets hit at a local railroad crossing, everyone slows down at crossings and looks real hard both ways for trains for few months, then the effect gradually wears off.

Getting Vaccinated-

Reported propeller accidents, just like railroad crossing accidents are rare in many communities (thank goodness). When a serious propeller accident is reported, the local area is impacted. Some boaters will be directly involved, others will know those injured or killed, others on the boat(s), rescuers, police, fire departments, paramedics, doctors, nurses, family members or others involved. Still more will see it on TV, reads about it in the newspaper, hear it on the radio and overhear people talking about it on the street, at work or at the marina. During this community “healing” process many local boaters become “vaccinated” with a “perceived vulnerability” resulting in an increased desire to take proper boating safety precautions so something like this does not happen to them. They may especially take precautions that could have prevented this exact accident. But gradually over time, just like a vaccination, the accident wears off, they go back to their old ways, and unless they get a “booster” (hear of another similar accident), the cycle is repeated, but this time perhaps with them as the victim.

Long Distance Vaccination-

The same effect can result from a similar accident at a distance (like in another state) when a boater has a personal connection to the event (know someone involved, etc) in the distant state. However a local accident has larger local safety impact on a given boater because many other boaters around them may also be obeying the rules of the water more closely, instead of just them.

The vaccination concept is an outgrowth of our 8 July post on the article by Mr. Brent Wheat in the 8 July 2007 Journal and Courier article.

Dosage –

Not all propeller accidents are the same in terms of their ability to inoculate boaters with a perceived vulnerability to propeller accidents. Accidents caused to law abiding boaters by those doing illegal or stupid things have less impact on the behavior of many law abiding boaters than accidents they see as being more preventable, such as when someone strikes one of their own family members with a propeller while obeying the law. For example the 8 July 2007 accident at Old Saybrook CT where a runaway boat ran over a sailboat killing one and injuring three and the powerboat operator was suspected of being intoxicated. Many local CT boaters will think that accident was not preventable from the standpoint of those who were injured. As a result they will not make great efforts to take boating safety classes, etc. On the other side of the coin, accidents involving seemingly law abiding boaters running over their own family members with propellers probably have the greatest impact on other boaters. They can see that happening to them and feel the accidents are preventable. As a result, some local boaters will try to change their behavior to be safer, at least for a while.

Bad Guys Impossible to Avoid –

A paper from the AAA Foundation for Traffic Safety makes yet another point. They note news coverage of fatal automobile accidents often makes somebody out to be at fault. This can make drivers feel there is little they can do to protect themselves, so why worry about it. Seems like the same concept may apply to news coverage of fatal boating accidents? (as mentioned in the “dosage” section above.)

Over Reporting of Categories –

The AAA paper goes on to note the media often over report automobile accidents involving teens and/or alcohol which can give the middle age non-drinker an untrue sense of being invulnerable. Once again, boating may be experiencing a similar process. Middle aged boaters who don’t drink near the water may think they are bulletproof to marine accidents.

A few references that may be of interest are:

  • Terrorism as Hazard: A New Species of Trouble. Paul Slovic. Risk Analysis. Vol.22. No.3. 2002. – talks about the social amplification of some risks, some events have large “ripple effects”, what conditions foster extreme vulnerability, etc.
  • Aspects of Meaning and Relevance in News Media Coverage of Motor Vehicle Accidents. John Martin, Karen Smith, and Monica Worth. AAA Foundation for Traffic Safety. 2007.

A related concept we would like to propose is a counter at major lakes or recreational areas that displays the number of days since a major boating accident (maybe since a death?). We are used to seeing clocks outside factories saying their workers have gone so many thousand hours without a lost time injury, why not a similar boating safety clock. The digital sign/clock might inspire boaters to be safer to extend the clock. It could also make them aware when major accidents occurred so they might be “vaccinated” by them. The clock might count days or hours depending on the location. More widespread, consistent application of boating safety practices will also reduce propeller injuries.

8 July 2007 Reasons for not obeying water safety laws – I just saw:
Obey Water Safety Laws.
by Brent Wheat.
Journal & Courier of Lafayette – West Lafayette IN.
8 July 2007.

Mr. Wheat suggests most boaters know several boating safety tips (wear a life jacket, don’t drink, don’t try to swim across the lake, don’t let kids hang their feet off the front of your boat while underway, etc.) He postulates that the first time we go to the lake and come home safe we think we are experts at staying alive in the water. Then every time afterwards, it reenforces those thoughts and it begins to seem reasonable that nothing could happen to us in the water. AND, if it did, we could save ourselves. He points out government regulators consider water a life-threatening environment for workers (like divers). He makes some good points about how each trip can make us feel a little more bulletproof in our minds. I would like to add I think geography plays in there too. Major boating accidents (and more specifically propeller accidents) happen scattered around the country. Areas that have one are locally impacted. People actually see it, know someone involved, hear local people talking about it, see it on local TV, read about it in the news paper, and swear to themselves to be a little safer. But, over time that wears off and they go back to their old nonchalant ways, while areas without one for some time, are perhaps more likely to have one due to attitudes.Thanks to Mr. Wheat for making a good point.

6 July 2007- Whats Your Plan? I just saw a youth “get out the vote” group (Student PIRGS) on TV that is taking major issues affecting young people (health cost, global warming, student debt, etc) directly to the presidential candidates and asking them, “What’s Your Plan?”. Are we the only ones noticing the carnage going on with towed tubes? Tubers are being hit by props at what seems like an exponential rate. “What’s Your Plan?” When will a drive company say the “T’ word (tubes) and at least recognize the problem? Shortly or when hell freezes over? I am not sure exactly what the plan should be, but I am sure it shouldn’t be the status quo. Seems like some five fold approach of propeller injury protection devices, increasing the visibility & awareness of those in the water, boating safety education, reducing or eliminating alcohol consumption, and limiting tubing in higher traffic areas and on holiday crowded lakes might be a start? If any body has any comments or suggested approaches please contact us.

5 July 2007 – Propeller Injury Counter – I noticed a 29 June 2007 Wall Street Journal column by Carl Bialik titled, “Countdown Clocks Offer a Lot of Drama But Little Information” that discusses some of the better known digital countdown and countup clocks around the country and world (U.S. National Debt, World Population, Number of People With Aids/HIV, etc). Reading it I recalled seeing a huge one in Japan several years ago counting down to the Millenium. Also, I recalled seeing several articles recently on the exploding popularity of “widgets” (small programs that perform tasks for you) – some are easily set on desktops or blogs and that some of them are counting down till major concerts, etc. A countup clock widget counting reported propeller injuries and/or deaths might draw some attention to the problem? The Wall Street Journal pointed out that many of those “clocks” are estimates that are adjusted from time to time, just as the prop strike clock would need to be, but they still receive a lot of attention.

27 June 2007 – Impact of higher horsepower engines and outboard motors – horsepower ratings of inboard, stern drive and outboard engines have significantly risen over time. Outboards have really jumped the last few years, plus the industry is strongly promoting TRIPLE outboard installations. You can see them on the front cover of countless boat magazines, advertisements and articles. In the past duals /twins were rare, now triples are feature stories everywhere with quads even showing up occasionally. This rapid expansion of horsepower engines results in both higher speeds and in more propellers in the water. Higher speeds seem likely to result in more propeller injuries because (1) less reaction time when you see someone or something in the water in front of your boat, (2) more people being ejected from the boat when maneuvering sharply. But a third reason is what started this entry. If people are randomly placed floating in the water of a lake (like when they fell from skis, wake boards, or a tube), the same number of boats going faster creates a longer track of surface area covered by boats per minute than slower boats. Imagine a lake with 5 small outboard powered fishing boats putting around, vs. the same lake with 5 high performance boats zooming all over the place. Every minute the small fishing boats might traverse “x” linear feet of the lake while the high performance boats would traverse “many times “x”” linear feet of the lake, thereby having a much higher probability of running over a person randomly placed in the water they did not see. This higher probability is perhaps even double, or tripled when multiple engines (multiple propellers) are used on the high performance boat. Higher powered boats may also result in people falling from skis, wake board, or tubes more frequently than lower powered boats, thus placing them at risk more frequently? These thoughts are obviously just speculation. We would welcome the thoughts of others on this matter and especially any research that may have been done in this area.

24 June 2007 – Survivor Advocacy – for some time I have been looking around to see if somebody has studied the process by which a cause (like kids locked in trunks, kids locked in refrigerators, kids drowning in swimming pools, ATV injuries, carbon monoxide on houseboats, etc) rises from obscurity to prominence and action is taken. I thought we might learn something from other “movements” that might be used to help prevent propeller injuries. In the past, I have identified some other groups promoting propeller safety and listed them in our Propeller Safety Advocates, Sites of the Injured, & Related Sites Links, plus I was aware that most of those groups were formed as the result of a single propeller accident that deeply impacted the founder (such as loss of a family member). I was also aware several manufacturers of propeller guards and related devices started their operations as a result of witnessing a propeller injury or otherwise being influenced by a specific propeller injury accident.

Last night I came across the term “Survivor Advocacy” for the first time. It refers to survivors of tragic accidents that go on to be advocates for removing the cause of the accident. Common threads per an article in the Injury Prevention Newsletter include:

  • Remembrance of their loved ones
  • Personal and passionate efforts to eliminate the problem
  • Feeling a singular responsibility to do something to prevent future tragedies
  • Feeling like “Lone Ranger” at first (like they were the only one working on it)
  • Smart resourceful people going up a fast learning curve on advocacy and the technical issues behind their cause
  • Devoting large amounts of time and money to the cause often at the expense of their family’s stability
  • It became all consuming (everything else was second on the to do list).,/li>

I found a handful of technical papers on the topic and listed them in our Survivor Advocacy section. These papers provide insights into the individuals behind several somewhat similar causes. I have yet to be able to study them in depth, but found them very interesting as I quickly over viewed them. Among groups started by survivor advocates are:

  • MADD – (Mothers Against Drunk Drivers
  • Handgun Control Inc.
  • National Head Injury Foundation (now the Brain Injury Association)
  • The Danny Foundation – baby crib corner post height standards
  • Kids in Danger – getting recalled children’s products out of circulation
  • Drowning Prevention Foundation – prevent childhood drowning
  • Stop for Kids Safety – kids and traffic
  • Californians for Safe Motorcycling – motorcycle helmet law
  • Safe A Life Foundation -first aid and CPR training to first response professionals
  • TRUNC – inside releases for automobile trunks
  • KIDS’N CARS – children left unattended around cars

I will further study survivor advocacy in the future and see if we can learn some things that might make us more effective in preventing propeller injuries.

24 June 2007 I came across Advocates for Highway and Auto Safety, an alliance of consumer, health and safety groups, and insurance companies and agents working for safer roads. Maybe something similar might be useful for propeller safety?

18 June 2007 – thinking about the parallels of boating and automobile accidents and the documented frequent involvement of alcohol in both – I began wondering if drunk drivers are responsible for making cars safer. There is no doubt the automobile accident count is much higher due to the use of alcohol than it would be if all drivers (and passengers) were stone cold sober.

I suspect we may owe many of the “niceties” of automobile safety to drunk drivers. Things like air bags, recessed door handles, break away mirrors, shock absorbing bumpers, seat belts, door panel braces, passenger air bags, etc might have not yet have come into existence or at least not come into existence as early as they did if not for the additional crashes caused by impaired drivers.

Automobile engineers have responded to the accident counts (probably in part due to government mandates) by designing safer cars to keep the injury and death counts down.

The automobile industry does not seem to have taken the stance, “they brought it on themselves by making poor decisions, by drinking and driving. Our cars are safe if they are sober, it’s their own fault.” While the boating industry seems to have taken that tack. Over the last many years, alcohol has obviously been involved or a root cause in thousands of boating accidents (including several propeller accidents). The boating industry seems to respond to propeller accidents saying they brought it on themselves, or write off the accidents as being alcohol related and thereby not deserving of design changes.

I am certainly not promoting drinking and boating, in fact I promote not drinking at all. However, in today’s boating environment, it is going to occur. Why not recognize it and design safer vessels just as the automobile industry has responded with safer cars?

17 June 2007 – reflecting on coverage of a 11 June accident on Lake Susan in Minnesota, I caught myself mulling over vast changes in boat operators and users in towed sports since my youth. When I grew up in the 50’s and 60’s many dads pulled their family and friends on skis behind outboard powered boats. The population was rural with a strong respect for rotating mechanical devices as most of us only had to go a few miles in any direction to visit with a one armed farmer. Today’s participants come from urban settings, many without a clear understanding of the dangers of rotating equipment. In the 50’s and 60’s we were much more reserved on the water (and everywhere else). Plus horsepower (and speed) were diminutive by today’s standards. Our teachers may have complained about our attention span, but they would have been thrilled with us compared to today’s iPod generation. A June 12 video interview (click on the 10 pm video report) with the young man injured in Minnesota by television station KARE 11 reveals some of the differences I am talking about. Today’s towed sports environment requires greater attention by participants, safety and engineering professionals, boat and drive manufacturers, boating safety educators, and others. The current spike in tubing related propeller injuries may only be the tip of the iceberg if these problems are not addressed soon.


Stop That Prop
Stop That Prop

12 June 2007 KARE11 (Minneapolis-St. Paul MN) “Man Injured in Boat Accident on Lake Susan” reports a 21 year old male from Chaska was loading a tube into the back of a boat on Lake Susan “when his leg and swimming trucks became entangled in the propeller.” Firefighters from pulled the boat to shallow water and freed him from the propeller. Officials reported if he had been entangled with his head underwater “this would be a very unfortunate situation.”

15 June 2007 – on 12 June 2007 Minnesota Dept of Natural Resources (DNR) “DNR Issued Safety Reminder for Boaters to Stop That Prop”. The announcement comes as a result of a June 11th high profile propeller accident on Lake Susan. They have a new “STOP That Prop” sticker warning boaters to shut off their engines when picking up or dropping off skiers or tubers. We think this is a great idea and encourage other states to follow suit. Plus if you are a Minnesota boater, please contact them and get your decal. Yes, we know warnings are not the answer in and of themselves.

14 June 2007 – After watching a June 12 video of a young man who got his leg and swim trunks caught in a prop in Minnesota on KARE11, his comments about I didnt know the prop was still turning or I thought the prop was stopped, echoed in my head with great similarity to “I didn’t know the gun was loaded”. There may be some concepts, methods or approaches from groups trying to prevent accidental gun shootings that might be translated for the boating audience? Like the old “Treat Every Gun Like A Loaded Gun” to “Treat Every Propeller Like A Rotating Propeller” but with current boat design and ladder placements that would be hard to safely do (give them enough distance) in many boats. Perhaps there are other approaches used to teach firearms safety.

29 May 2007 – Just noticed a post in an Australian publication (already tomorrow down there) about marine rescue professionals throwing ropes into the path of an unmanned boat (operator had been ejected) to foul the prop and stop it from running over people. This fits with my “foul the prop” invention idea mentioned earlier in the technologies list (see “Fouling the Propeller on Purpose” a section near the bottom the list. The concept of throwing ropes in itself might be useful to circulate to boating safety professionals who are sometimes faced with this task. (Throw lines and ropes in front of a runaway boat to stop it so dont have to wait for it to run out of gas or try to board it while underway.
Reference – “Warning: Extra Care Needed When Boating Alone”. Sail- 30 May 2007.

27 March 2007 – Today the news is full of coverage of the death of a Coast Guardsman, Ronald Gill, in Puget Sound on Sunday 25 March. He fell from a 25 foot fast response boat, his head hit the propeller, and was declared dead at a local hospital. At this time, our hearts go out to his family and friends. We also wonder if the death of one of their own might raise the intensity of focus on propeller injuries by the USCG?

3 March 2007 – I noticed the International Atomic Energy Commission (IAEA) recently changed the radiation warning symbol, in part because some kids thought the old symbol just looked like a propeller and did not indicate danger. See “New Symbol Launched to Warn Public About Radiation Dangers” 15 Feb 2007 report on the IAEA web site. The new symbol definitely conveys danger stronger than the old one. Although warnings are to be the last step in a many step process to insure safety, the boating industry might consider a much more “in your face, danger, run away” decal like this one than the somewhat vague decals we see on some boats, many of which cannot be seen from the water and do not even mention the word “propeller”.

The NMMA posts a decal they call “PROP TRANSOM LABEL (NW 208-07) – This label is required in ABYC H-41. It reads “Rotating propeller may cause serious injury or death. Do not approach or use ladder when engine is running.”” It is shown below.

Radiation Warning - Old Style

Radiation Warning - Old Style

Radiation Warning - New Style

Radiation Warning - New Style

NMMA Propeller Warning Decal

NMMA Propeller Warning Decal

4 Feb 2007 – yesterday, someone pointed out MariTech, a major manufacturer of propeller guards and several electronic propeller injury avoidance devices has completed a major update to their web site (and relocated it). Part of their approach is to segment visitor to their site by boat type, then show the range of products applicable to that user. I think they did a nice job. You can see their new site at

We continue to work on a somewhat similar approach trying to create a scorecard to give a boat an indication of their relative risk to propeller injury AND then suggest a suite of approaches and alternatives for their boat, operating conditions, activities, environment, experience, etc.

23 Jan 2007 I came across a very unusual web site, Speedo-Mat discussing a computer virtual / physical world interface resulting from a FAB Workshop in Switzerland in which “real” small airplane propellers are modeled along with input from “real” people to create “virtual” people that can be sucked into the “virtual” propellers in real time. It is an interactive interface. This concept might somehow be applied to real life boat prop situations?

9 Jan 2007 – I came across a 1996 paper developing a model for collisions of birds with windmill rotors. Some ideas and concepts put forth by them might be useful in this application as well.

  Using a Collision Model to Design Safer Wind turbine rotors for birds
  by VA Tucker
  Journal of Solar Energy Engineering
  Transactions of the ASME Vol.118 No.4.
  Pgs. 263-369. November 1996.

The paper develops a mathematical model for collisions and defines a safety index that allows comparing rotors of different sizes and designs, including wind speed (i.e. boat speed). Bird carcasses counts below rotors tend to confirm the model.

24 Dec 2006 – Recently I came across a New York National Public Radio program addressing stress that visits with a propeller strike victim about the actual event of being struck and what goes through your mind. The episode titled “Stress” aired on 11 Feb 2005 and was available as on online sound file. The program is a bit irreverent at times, but the propeller injury segment is pretty “matter of fact”. It begins at about 5 minutes: 5 seconds on the timer and ends at about 12 minutes: 40 seconds giving it a run time of about Seven and a half minutes. You may need to “scoot” your browser our of the way to see the audio timer, then adjust it using the slider. Coby Hall (spelling uncertain) describes being hit by the propeller of a ski boat that seems to have been left slightly in reverse. He was preparing to ski and it backed into him while the boat operator was tending to the ski rope. The accident occurred in Vermont on a July 4th weekend (year not certain).

21 Oct 2006 – Recently we read a Wall Street Journal article on the increasing use of motivational speakers by companies as their employees have soured on the traditional high powered executive speakers that have been caught doing everything wrong. Today, I came across a small community story about a motivational speaker, Todd Huston, coming to an area and back tracked it to his web site. Todd Huston suffered a major propeller injury at age 14 which eventually led to the amputation of one of his legs. Now he is on the motivational lecture circuit.

13 Oct 2006 – I had an idea for a “hinged, planing propeller guard” for houseboats, party barges, pontoon boats, and other displacement vessels. It hinges in the area behind the cavitation plate of outboards and stern drives and just flips up on a “planing tab” when underway forward to reduce drag. It stays down when the boat is stationary or in reverse to protect people in the water behind the boat. More details and a sketch are available in my 13 Oct 2006 post on our Propeller Safety Technologies page.

8 Oct 2006 – We are starting to see propeller accident photos and guard discussions turn up in the rapidly emerging Internet Networking sites (MySpace, Flickr, Facebook, YouTube, etc). For example this guard photo on Flickr taken 26 July 2006.

16 Sep 2006 – It recently came to mind there are some parallels between propeller guards used to protect propellers from hitting rocks and other obstacles and cowcatchers (knock cows of the railroad tracks in the old days). Wikipedia says the correct name for them is pilot. Both have somewhat of a V-shape and try to deflect objects. Some prop guards try help the drive ride “up and over obstacles” while cowcatchers tend to throw cows and other obstacles up and out of the way, but still some similar things happening. I wonder is their are other similar historical situations out there we might learn something from? It might be interesting to look at some cowcatcher patents (if there are any) and see what patents they cite as references/inspiration.

4 August 2006 – “Which Came First the Chicken or the Egg?” somewhat describes problems in the business side of the propeller guard industry. End users are thinking, my boat is so and so length, I have a certain horsepower drive, it is a certain type of drive (outboard, inboard, stern drive, etc), built by a certain manufacturer (Mercury, Honda, Yamaha, Bombardier, etc), with a certain propeller and I use my boat for these specific activities (ski, fish, runabout, tube, entertain) in this specific environment (a certain lake or area). My choice of high quality propeller guards currently on the market at a nice cheap price for my exact application is limited to nonexistent. From the guard manufacturer standpoint, they are typically small companies, several of which were formed by people impacted or inspired by a propeller accident. They don’t have huge financial resources to develop a wide range of guards to fit across broad applications (lots of sizes, lots of motor types, lots of applications), at a range of price points. They tend to be single product companies (we make propeller guards we don’t sell anything else). It is not a mature industry (is certainly not like the outboard motor industry where several players have broad, deep product lines with worldwide distribution). Its a bit of the chicken or the egg. The small companies making guards have trouble getting over center to be able to tool up and manufacture a broad line with the current limited demand. I noticed one comment in a discussion suggesting a tax credit for purchase of guards as a way to possibly push things off center. I am not sure about that approach, but a discussion within the industry of ways to help push things off center (other than mandatory regulations) might be helpful. I seem to recall the state of California requiring a few percent of their automobiles to be electric powered or otherwise near zero emissions to stimulate developments in that field. Perhaps a similar approach by one or more states could be taken with propeller guards (possibly including some of the other propeller injury avoidance devices as well). The marine drive industry is currently willingly being “taxed” to support the Grow Boating initiative. Perhaps a similar approach or part of that money could be used to support a pilot program (subsidize the purchase of guards a little bit). It would obviously require some serious thought but might be structured to provide at least a base market for some of the existing manufacturers and might encourage some more to enter the market, as well as to inspire continued development of even better products in this area that could help save lives and make boating safer. Sounds like a good way to Grow Boating to me. If have any comments about any of these approaches, another approach to suggest, or other comments, please contact us.

A related thought would be for outboard and stern drive manufacturers to make their drives a little friendlier to bolt on guards by providing a somewhat standardized surface on their anti-cavitation plate and leading edge of the drive to work from (to mount to), plus perhaps some bosses setup for holes to be drilled to mount them. That’s obviously way out there in the realm of things that would probably ever happen, but an interesting idea. If the drive manufacturers ever start offering guards themselves, those features will probably appear.

27 July 2006 We noticed the Double Angel Foundation a group started by parents of two children who drowned swimming behind a houseboat at Lake Powell due to Carbon Monoxide poisoning is facing a similar cause (houseboat carbon monoxide poisoning) with a somewhat different approach. We might both learn something from each other.

25 May 2006 – A recent Wall Street Journal article on searching for the body of a missing pilot in Flathead Lake near Polson Montana (town named for a possible relative of mine) decades after his crash may be interesting to those searching for bodies never found in the water. “A Pilot Reaches Deep to Plumb the Mystery of Another’s Crash. Wall Street Journal. 23 May 2006. Pgs. A1 and A11. It mentions a couple (Gene and Sandy Ralston) from Kuna Idaho that specialize in this type of recovery, plus their use of a Black Labrador named Ruby trained to smell remains in the water along with a sonar equipped boat and remote operated vehicle. They appear to have been successful in finding this pilot over 45 years later in 250 feet of water. A related article appeared in a Montana Paper, the Daily InterLake on May 8th.

27 April 2006 – Many have argued that traditional propeller guards create additional safety hazards (wider cross section creates larger zone of potential impact, potential entrapment, etc). A somewhat similar case is being played out in the press right now with defibrillators.

Case Grows for Leaving in Recalled Defibrillators
Wall Street Journal
26 April 2006

The article above reports a 13 year period study published in JAMA (Journal of American Medical Association) based on data reported by manufacturers to the FDA (Food and Drug Administration) that from 1990-2002, 31 people died because their defibrillator failed to function properly, out of 415,780 installed. During the same period, “thousands of people had their lives saved because defibrillators properly shocked their hearts back into proper rhythm.” Corresponding data for traditional propeller guards is not available, but this parallel situation may be of interest to those studying the potential impact of traditional propeller guards with respect to the potential hazards they may also create. The defibrillator “recall” situation has been prominently in the news the last few weeks.

27 April 2006 – yesterday I ran across a 1976 old boating safety study that might provide some guidance to more current studies utilizing safety analysis techniques to analyze propeller injuries. Plus reading it thinking about prop guards raises a point not previously considered. Could prop guards cause injuries through some people choosing to become additional risk takers near propellers with guards (hey, its got a guard, its okay to swim back here with the prop rotating, etc).

Boater Decision Making
M. Pfauth, C. Stiehl, G. Lancaster
Wyle Lab, Huntsville AL
Available NTIS
AD-A040 970
Prepared by Dept of Transportation
Coast Guard Office of Research and Development
November 1976
56 Pages
DOT-CG-40672-A, T.O. 21
It is also listed in Water Resources Abstracts

The study tries to determine if their is a common cause for capsizing, sinking a swamping of small boats, then to determine if any design changes might help, and to determine if any behavioral problems, such as increased risk taking, would result from these changes. When considered in the “propeller guard” realm, this study opens up a concept we have not previously seen mentioned anywhere – Would propeller guards increase risk taking? Would some people feel safe in the water knowing a guard was in place and place themselves at risk that would not have otherwise done so? Would they be swimming near a rotating propeller betting on the guard protecting them when they would not have done so previously?

26 April 2006- “VW Uses Shock Treatment to Sell Jetta’s Safety” Wall Street Journal. 19 April 2006. Pg. B4. – Volkswagen is showing pretty graphic car crashes on TV to tout the safety of it’s Jetta. The story reports the ads are so realistic, people are calling in and asking if any of the actors were hurt. It goes on to discuss how ads like this might backfire due to their content. – Perhaps this approach might be used to sell propeller safety devices?

29 March 2006 – Marine drive manufacturers implement Six Sigma type programs to improve product quality. Employees are continuously educated about their quality system/process. They have Quality Departments and highly trained personal looking after the overall quality system. Engineers put additional thought into part and assembly designs to make sure their processes can stay far away from the boundaries (typically the tolerances) where problems will begin to happen. They carefully monitor process data. When a problem does occur, they collect large amounts of data from the defective part(s), follow the process backward to determine the root causes of the problem, determine how to eliminate the problem from surfacing again, implement the changes and follow up on them.

Similarly, they have major in-house safety programs structured to reduce employee injuries on the shop floor. Employee education in a big factor. They have Safety Departments manned by safety professionals, as well as Safety Teams composed of people on the floor, They put extra thought into production line and assembly line areas to make sure their process are safe and stay far away from ways people can hurt themselves (pick up too much weight, pinch fingers, catch fingers in press, burn arm on hot surface, breath bad fumes, etc). When an accident does occur, they collected). When an accident does occur, they collect large amounts of information surrounding it, they try to determine the root cause and eliminate it to prevent future accidents. Then they follow up with careful observation to make sure the changes really lead to safer operation. Locally, Brunswick has major celebrations, and rightfully so when MerCruiser passes a Million Man Hours without a lost time accident. In October 2005, Mercury Marine announced Plant 15 in Fond du Lac reached 2 million man hours without a lost time accident. These are tremendous accomplishments and take great efforts by staff and employees to achieve.

BUT, when you flip over to product safety in the field, no such system exists. No evidence exists of major efforts by marine drive or boat manufacturers to collect detailed data surrounding propeller accidents so the problem(s) could be better understood and quantified and analyzed in manners similar to their quality and employee safety systems. The Coast Guard makes some efforts to report counts, but a count and the typical data collected by the Coast Guard do not provide the type of details needed that could really open this area up to innovation as well as better select which messages would be most effective in boater education. We tried promote the Creation of a Boating Industry Consortium to Address Propeller Injuries in December 2002 that would focus on collecting high quality data on propeller accidents and are still waiting for the first phone call.

Recently I came across a twenty plus year old article:

Gruesome Tale of Horror May Eventually Save Lives
Miami Herald (FL)
25 March 1983

It focused on the old stick steering bass boats of the 1970’s that ejected several operators due to their sensitivity, throwing some of them in the path of the propeller. When asked about how many of these actually occurred: 

“Lysle Gray, Chief of the United States Coast Guard Product Safety Branch, says that no statistics are available on the number of such accidents because “they usually happened in inland lakes and rivers, places they were investigated by local sheriff’s offices and not the Coast Guard. But they were not unusual, I can assure you.”

Its nice that tremendous improvements have been made in manufactured part quality and employee safety since 1983, but sad that similar methods to those used by Quality and Plant Safety Professionals have not been used to improve the safety of their customers.

29 March 2006 – Following up on the “Emission Credit” concept below (20 March 2006 entry) perhaps a series of test could be constructed like automobile crash tests, roll over tests, etc and “4 Star”, “3 Star”, etc. Propeller Safety ratings awarded to boats depending on how safe the combination of boat, drive and propeller are in a specific combination of situations (might be tested with lifelike mannequins, etc). Then taxed based on performance of current units as well as their efforts to retrofit improvements into the field. Plus the “Star” ratings could reward safe products by consumer demand in the marketplace and be an incentive for others to “catch up”. Plus the actual performance type ratings would not force use of any protection methods not needed in a specific combination (not defeat innovation to solve the problem outside traditional prop guards).

20 March 2006 – There is already an “Emissions Credit” market where companies buy and sell certificates allowing them to go ahead and pollute beyond the regulations by purchasing some of the “ability to pollute” from other companies that did not pollute as much as they were allotted. What if we had a “Propeller Injury Credits Market”? Companies could be evaluated on their average contribution toward propeller injuries over the last few years to set a baseline. Then the government could ask them to reduce those numbers to new targets (like everybody reduce by 50 percent in three years on new equipment and by 20 percent of units in the field) then those companies that did better safer designs, addressed field populations and reduced their impact by greater than the target percentages could sell the gap (their improvement below the target) to companies that did not improve or did not improve enough. This type of program might create an incentive for companies to actually act. If it seems too difficult to define a particular contribution to a specific company, maybe the whole industry could be assessed (sort of a tax on every drive/boat) and some peer pressure put on it to achieve better results? If the whole industry was taxed, the funds might be used to fund research in this area, educational programs and other aids? Not sure if “Propeller Injury Credits” is a good idea or not, but it might stimulate some discussion.

7 March 2006 – We just received minutes of the Propeller Injury Avoidance – Carbon Monoxide Workshop< held 17 Feb 2006 at the Miami Boat Show. The last two pages – Pages 61 and 62 are a statement from SPIN pointing out the large circle of people (and generations) impacted by a propeller accident. We have independently been working in this area the last couple days and had some substantial finds and revelations in this area (above and beyond the way all accidents impact others). We will be organizing and presenting our thoughts in this area as time permits. I found it very interesting that SPIN independently raised the same issue at the same time. That helps confirm my thoughts we are on to something worth further pursuit. The tack/approach we are currently toying with on showing the circle of impact is a bit different, but I think both approaches may have significant impact.

28 Feb 2006 – Physical representation of propeller danger idea – For many years the Oklahoma Highway Patrol has drug around a trailer mounted accident simulator that can be raised to an incline to allow people to be strapped in, slide down the incline and simulate a slow impact (maybe 5 mph) to feel the amount of restraint seat belts provide to encourage people to wear seat belts. They setup and operate the simulator at large public gatherings (fairs, special events). Perhaps a device could be constructed to physically impress the danger of propellers on visitors to similar venues (like boat shows, recreational events)? The accident impact simulator does not seem to have any negative impact on car sales (and is not intended to). To gain widespread use at boating events, a Propeller Danger simulator would similarly need to be framed in a method to focus on the danger of propellers, not on the danger of boating.

28 Feb 2006 – Graphical representation of propeller injuries idea- I recently viewed a CDRom presentation on the worldwide growth of a church. The presentation used a “movie” of global map with a year printed at the top. It set off a small light at the site of each new unit, then turned that light to a red dot that remained for the future years (the movie stepped forward a decade at a time). You saw the buildup (accumulation) of units across the world as each year rolled by. The same type of process could be used with propeller accident data to show the impact of the problem is not just a one year statistic, as well as to show global impact. The church presentation had a hymn playing in the background. A propeller guard presentation could also use sounds to increase its impact on viewers.

23 Jan 2006 – A Wall Street Journal article titled “New Legislation Could Scuttle Gun-Crime Suit” in their 18 Jan 2006 edition reports on a little known database in which guns used in the commission of a crime are traced back to the dealer selling it. In 1998, only 1.2 percent of the dealers sold the guns used in 57 percent of the crimes. Some are calling for manufacturers to shut down those dealers. Perhaps somewhat similar more in-depth recording of boats and drives involved in propeller injuries might find similar concentrations in certain regions, of certain types of combinations, of higher horsepower units in certain craft, etc. That knowledge could be used to help prevent future injuries. We first promoted an Propeller Safety Industry Consortium to gather such data in 2002, but have still not had a single response from the industry.

10 Jan 2006 – I have been reading “Fault Tree Analysis for Assessing Propeller Guard Injury Prevention Effectiveness” by T.A. Kress and R.L. Kress and presented at a Biomechanical conference in Greece in 2003, along with reading some other technical papers on the use of “fuzzy” fault logic trees to make decisions and thinking about how a survey might be taken to estimate the relative frequency of some events of an expanded version of the fault tree proposed in the Kress paper, possibly providing a means of identifying the most critical situations (sizes and types of boats, activities, and conditions) currently resulting in propeller injuries so those situations could be addressed first. Access to the actual database used to produce reports like the California Boating Safety Reports and similar national reports from the Coast Guard might also be used to estimate the “fuzzy” levels by providing condition details for individual propeller accidents when they were available.

10 Jan 2006 – In reading the program for the International Conference on Probabilistic Safety Assessment and Management held in Germany in June 2004, it appears some of these tools and methods might be applied to better understanding propeller guard issues. Then I began to wonder if the ORDEM2000, the NASA program to estimate the frequency and severity of satellite impacts with orbital space debris we once used to estimate propeller impacts with debris in the water might also be modified and used here?

9 Jan 2006 – Back to encouraging university students to conduct class / team projects in this area, I was recently approached by a Made in Egypt competition that looks like a nice model that could be followed here as well.

5 Jan 2006 Bad Press Research – we or others might do some work to help manufacturers quantify the direct financial impact each one of these accidents has on new boat sales among those reading / hearing about the accident in the media or in passing conversations, as well as just reading about the problem in general (reading about past accidents now in trial, or even in passing like when some articles about a totally different subject mention a propeller injury to someone in the article.). I have not had time to look, but suspect some work of this nature may have already been done in other fields (like ATV rollover accidents, accidental shootings, Pinto fires, SUV gas costs, etc) that might supply sort of a template for research in the impact of propeller injury “bad press” on boat sales. Many articles have recently touted the importance of women in making the decision to buy a boat. I suspect they are even more likely to “bail” from a reading or hearing about a prop accident than men. Some research might also be done in regions recently impacted by a major propeller accident (local sales history, boating activity levels, comments from locals, comments from local boat dealers, etc).

5 Jan 2006 A Scuba Diving Risk Assessment for a specific event might be a good model for trying to create a similar style chart for the various types of boats and boating activities to better quantify and communicate propeller injury risk levels.

15 Dec 2005 Aviation and other industries log “close calls”. Much might be learned from studying propeller injury close calls. Like how did they about get injured (could that be prevented), how did they avoid injury (could that window be expanded), and the frequency and nature of close calls.

15 Dec 2005 Many feel propeller injuries do not receive the industry/media/regulatory/public attention they deserve. Shark attacks are parallel to propeller injuries in many respects. Both events occur in the water while involved in recreation, often occur close to shore, often in view of family and friends, both can cause horrific life threatening – life changing injuries, both frequently involve life flight transfers to major hospitals and amputations. Shark injuries are extremely rare compared to prop injuries, but shark injuries get tremendous attention from the media and the public seems spellbound by them. In part possibly due to some inherited fear of or fascination with these terrible beasts and due to the Jaws movies and all the shark hand puppet toys? Maybe something could be learned from a further discussion/study of this comparison that might identify some means of raising the awareness of the propeller injury issue?

14 Oct 2005 I wonder if some of the work we have done on mathematically modeling boat drag (including the drive) from “coast down” data might be an effective tool in estimating drag for some of the cage and ring type guards. I will pursue this further when we get some time.

4 Aug 2005 I recently came across a plane crash site called Plane Crash Info that databases information on airplane crashes. We might try to incorporate some of the techniques and methods used by that site in logging prop injuries.

20 July 2005 If the industry can “tax” marine drives to support the “Grow Boating” initiative, maybe they should consider “taxing” drives/props to fund research to minimize propeller injuries?

31 May 2005 Recently, while updating the site and putting some names, faces and lives with those injured I have had several thoughts surrounding various themes of the propeller guard, propeller injury field and decided to begin listing them here.

  • An industry competing with boating (like RVs), might consider an anti-boating campaign using the recent carnage of youth and others by propellers as a means to help purchases decide if they wanted to buy an RV instead of a boat.
  • An injured high school or college student or a similar youth, friends with an injured/ killed person might wage an “all out” Internet war against the industry using recent accidents as ammunition. For $30 a month (Internet Provider fees) and their time, a skilled person might be able to bring the industry down? Later note- anybody who does not think one motivated individual can wreck havoc on an industry, see: Virtual Battle: How a Global Web of Activists Gives Coke Problems in India. Wall Street Journal. 7 June 2005. Pages 1, 6.
  • I suggest the Grow Boating Initiative consider the above two potential scenarios, plus the loss of life and limb AND the decrease in sales to potential new boaters resulting from these accidents, then determine how they might help solve the root cause.
  • Wonder what kind of response you would get from a jury after you asked a drive manufacturer what percentage of their R&D budget over the last 20 years was spent on solving this long known problem?
  • For many years, drive manufacturers have said a decrease in operating efficiency (increased fuel consumption) is a major reason they do not use propeller guards. Wonder how much the efficiency of propellers has increased over the last 20 years? Is it possible they are now efficient enough to make up the loss that would have occurred 20 years ago (if prop guards decreased efficiency by 10 percent 20 years ago, is the average boat now propped where it operates 10 percent or more efficient than it did 20 years ago?) If boats are now as efficient with prop guards as they were without them 20 years ago, should we not use them? Seems like if that is true, the only anti-thesis would be we should not have been boating 20 years ago? I am not sure if props have improved that much, but if you combine them with hull improvements, the goal has probably been reached?
  • Similarly, right now their is a strong move to larger boats (use more fuel) and marinas are reporting strong fuel sales (See Boat & Motor Dealer Dec 2004 page 55). Both these events seem to indicate the market is NOT efficiency driven. If the concern was more emissions related than increased fuel consumption, why allow the move to larger boats (burn more fuel and create more emissions per boat than smaller boats)?
  • We have been helping an Industrial Design student outside the U.S. with a propeller safety project. Why doesn’t the industry encourage more student engineering/ industrial design projects in this field, along with masters & phd thesis? Students might be able to lay some good groundwork for the industry to build upon.
  • NASA uses software to predict the probability of impact with orbiting debris with spacecraft and the resulting damage. This software might be adapted to prop strikes? We have already used it in forecasting propeller life and found some interesting correlations. NASA calls it Orbital Debris Modeling.
  • I just saw the U.S. Army Corps of Engineers is now putting black flags on buoys on lakes and rivers they manage to mark where people have been killed. That’s another big reason to solve the problem. Its going to be hard to grow boating when potential boaters start asking what the black flags are for.

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