Two passengers were successfully launched from a parasail vessel for a ride aloft. As they were being winched in the winds picked up, and the parasail towline winch became inoperable and 800 feet of towline payed out stranding the passengers aloft. Additionally, the vessel was unable to make way through the water while battling rough seas and the strong winds, the U.S. Coast Guard said in a safety alert derived from a recent parasail casualty investigation.
The cause of the winch malfunction was due to overheating of the hydraulic power system which occurred because of an inadequate oil cooling system (through hull fittings / scoop type system) that relied solely on the vessel's movement through the water. When the vessel's movement was overcome and stalled by the wind acting against the parasail and the waves, there was no water circulation and thus no resultant cooling of the hydraulic oil. Since there was no fail safe braking system, the towline payed out when the hydraulic motor could no longer develop power. Three hours passed before the winds subsided enough to allow forward movement of the vessel, cooling off of the oil, and restoring the system to operation.
A series of parasail incidents resulting in fatalities and injuries have occurred over the last few years. Since 2006, there have been 11 deaths and 52 injuries as a result of parasailing activities. There have been several common factors in all of these incidents that are unique to parasailing.
This event was fortunate in that the parasail towline did not break and there were no fatalities or injuries, the USCG said, but nevertheless, to prevent similar occurrences, the Coast Guard strongly recommends that insurers, owners and operators of parasail vessels:
Ensure their vessel’s parasail winch hydraulic oil cooling systems are not dependent on forward movement of the vessel. If necessary, have the system modified by a parasail vessel professional.
Owners of parasail vessels which do have pressurized hydraulic oil cooling systems should ensure that their systems are properly fitted with inlet strainers on the sea water supply and that the rest of the system, pumps, motors, controls, oil filters, etc. are properly maintained at the proper frequency.
Review the USCG’s “Know Your Ropes” safety alert