Propeller Solutions Prop Deflector: August 2013 Update
We heard from our friends at Propeller Solutions in the UK last Friday (August 2, 2013). They are continuing to improve their vane / vein type guard called the Prop Deflector.
Propeller Solutions Facebook Page links to some of their recent test data and photos on Dropbox.
They also recently announced a new website specifically devoted to their Prop Deflector. The new website announces the Propeller Deflector being an Innovation Award finalist at 2013 SeaWork International, identifies their current models (which outboards they can fit – the list continues to grow), and shows off some nice photos of their propeller guard.
Propeller Solutions is trying to build a guard (deflector) that will deflect people from the propeller while providing minimal impact on top speed, handling, and other variables at speed. The new web site notes test results are showing only a 5 percent impact on top speed (even using the standard propeller) on a 30 knot RIB, and Royal National Lifeboat Institution (RNLI) is using them.
Test data shows a RIB running a Yamaha F60 small leg with a 13 inch Aluminum Turning Point Hustler Propeller doing 34 knots at 6100 RPM. When they added the Prop Deflector propeller guard they were still able to run 31.8 knots at 5800 RPM. Bollard Pull is essentially unchanged throughout the range.
One thing unique about the construction of the Prop Deflector is Propeller Solutions use of aerodynamic / hydrodynamic shaped tubing to form the veins. This makes the veins stiffer, provides less resistance, reduces weight, and decreases vibration / harmonics.
While they do not mention it, as they continue to refine the Prop Deflector, they may one day be able to size the tubing for the veins in a manner to allow them to be slightly crushed on impact to help reduce blunt trauma injuries at higher speeds.
Propeller Solutions mentions their Propeller Deflector being a bit of a backup for a kill cord.
As many of you know, the UK is really sensitive to kill cord related accidents following the Milligan accident at Padstow Harbor. This propeller guard / deflector is designed to provide protection in similar situations. Prop Deflector is especially applicable to rescue boats and to small and midsized RIBS in leisure and work boat applications.
We commend Propeller Solutions for bringing this propeller guard to market and for continuing to improve it.
Reference:
We first announced the Propeller Solutions guard back in October 2012.
Difficult to distil a case for guards given lack of scientific evidence/independent testing and having to run the gauntlet of:
– Cost V Improved Safety
– Cost + Performance Loss V Safety
– Has Safety been proved?
I am not anti. Just trying to gather intelligence to mount an argument “FOR”.
Thanks for your comments.
Guards are but one of many types of propeller safety devices that can be used in conjunction with behavioral modifications (leaving the alcohol and drugs at home), boat design (longer boarding ladders, no rear facing seats with no rail in front of them, etc.) and boating safety training to reduce the risks of propeller injury.
Plus the term “guards” is extremely broad. There are several different types and designs based upon vessels types (houseboats, pontoons, ribs, etc.), uses (skiing, boarding, runabout, fishing, partying, diving, work, etc.), waters (crowded, weedy, shallow, etc.), types of passengers (rentals, children, etc.), types of operators (rentals), boat speeds, etc.
If you want to mount an argument “FOR” that is pretty hard to refute today, I suggest you look at large rental houseboats and displacement rental pontoon boats.
We are very glad to see Propeller Solutions offer another “tool” to those seeking propeller guards for the applications they are intended.
Propeller Solutions is focusing on bringing prop guards (deflectors) to the table that bring the same advantages guards can bring to slower moving boats to vessels moving a little faster while avoiding the deteriorating characteristics that have been observed with some guards at higher speeds.
Gary