The 'Sea Scoopa' Concept

International Patents

'Man Overboard' (MOB) is the worst of all marine catastrophes as it accounts for 80% of deaths at sea. The difficulty of capturing and then lifting a person in heavy waterlogged clothing, half drowned and possibly unconscious from hypothermia or head injury onto a high sided vessel is always under estimated.

Capture difficulty is especially true if the MOB is "slippery" from a lack of clothing, clad in a wetsuit or covered with diesel fuel as occurred at the Christmas Island refugee tragedy. The impact of waterlogged clothing can be extraordinary. In a recent Tasmanian drowning the wet winter clothing and boots of the victim were weighed on arrival at the morgue, long after surplus water had drained, and totalled 74 kg!. With the modern epidemic of obesity, total loads up to 200kg will have to be anticipated. The Sea Scoopa has been NATA rated for loads up to 300kg.

The Sea Scoopa has been designed to achieve two objectives in facilitating MOB rescue:

1. SCOOP and securely net the man overboard, whether conscious or unconscious, whilst the boat is moving and has steerage at a speed of about 1 to 2 knots. All other methods depend on the boat being almost stationary and this creates enormous difficulties in manoeuvring alongside the MOB for 'pickup' in difficult conditions due to the action of wind and wave. There is compelling evidence that a vessel must have 'way on' to ensure successful capture of the victim. This is achieved by the unique and patented design of the SCOOP where the leading edge of the net is deeply submerged in the water to enable 'pickup' and the aft edge is kept at the surface of the water to prevent 'escape'.



2. PARBUCKLE the man overboard onto the deck in an horizontal posture. Parbuckling is an ancient technique used to lift barrels onto the decks of ships by passing two ropes around the barrel and heaving it up the side of the vessel. This acts like a block and tackle and provides a 2:1 mechanical advantage thus halving the effort required. This method was later adapted for MOB situations by attempting to use a small headsail to Parbuckle the victim aboard. However, this and other more modern versions of the Parbuckle were proven to be unsatisfactory in the 2005 San Francisco MOB trials. The conclusion was reached that 'had we been rescuing real victims three-quarters of them would have fallen out of the parbuckle during the lift'. In contrast, when the Sea Scoopa is deployed the MOB is very securely netted and lifted horizontally while gently rolling over and over like a 'chicken on a spit'.



HORIZONTAL LIFTING is now considered MANDATORY for all rescue situations where the victim has spent considerable time immersed in the water, is hypothermic, unconscious or injured. It is medically advocated for the following reasons:

* The lower body is compressed by the hydrostatic effect of the water, the so-called 'G suit' effect, and blood is diverted upwards into the chest cavity. The blood volume becomes progressively depleted by a physiological reflex causing excessive urination and the pulse rate slows as hypothermia develops. Vertical lifting causes immediate loss of the 'G suit' effect. The already reduced blood volume instantly pools in the lower body and the heart rate cannot increase to compensate for this sudden loss of central blood volume. As a result, circulatory shock and sudden death can occur. This is called “circum-rescue collapse” and is a well-recognised major hazard of vertical lifting. For further reading on this and indeed all medical matters concerned with marine rescue, one cannot do better than read the 'rescuers bible', which is Golden and Tipton's wonderful book entitled "Essentials of Sea Survival". This text should be in every Rescue Organisation's library.

* A semi-drowned victim who has swallowed seawater and is vomiting should never be kept flat on their back, as the fluid can spill into the lungs. The rolling motion ensures that during most of the lifting phase fluids will drain out of the mouth by gravity. In addition the 'log rolling' motion during the lift is advantageous if there is any suspicion of spinal injury e.g. hit by the boom.

* In dive boat medical emergencies where lung barotrauma and air embolism are strong possibilities, vertical lifting is absolutely contraindicated as it allows gas bubbles to travel up to the brain often resulting in a major stroke.



A CAUTIONARY NOTE.

Australian statistics show that 80% of deaths from MOB occur in mild to moderate conditions where complacency and alcohol can be factors. Another explanation for this paradoxical finding is that in severe weather most sailors become justifiably fearful for their lives and have the commonsense to wear life jackets with safety harnesses and clip on to the vessel with tethers.

There is no doubt that in extreme conditions such as those experienced in the 1998 Sydney-Hobart race the degree of difficulty in retrieving a MOB may be overwhelming. In these circumstances even with expert crew and the best equipment a mortality rate of close to 100% is to be anticipated. For this reason no guarantee is given or implied that the Sea Scoopa will be effective in all circumstances. In difficult conditions a number of other supplementary rescue aids should always be available to optimise the chance of success. These should include a Rescue Throw-Ring, SOS Dan Buoy, Lifesling and Seascoopa boathook.

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