After seeing the spectacular photos of the 55-foot yacht falling from the sling and sinking, it seems a good time for a discussion about how to properly haul out for maintenance and repairs.
The Carver Marquis that fell earlier this year did so when being off-loaded for delivery in a foreign port. But in my experience, which extends to all three U.S. coasts, lift operators here are also willing to cut corners far too often. Boat yards charge for time in the sling, so lifting more boats means lifting revenue. When people are rushing to get their boat out for the winter or in for the season, there may be a temptation to skip the details and move quickly.
As a boat owner, your defense against this is to be on hand for the haul out and to insist on certain safety practices, such as the right number of slings rigged in the proper configuration. I believe that the Carver accident could have been avoided if proper safety measures were in place.
TIE THE SLINGS: For starters, the slings that fit around the boat's hull fore and aft should always be tied together. This is supposed to be a standard practice, but in my experience it is a step that is frequently neglected unless the owner actually insists.
The yard manager may tell you in an indignant tone that the slings are always tied, but he may be unaware that the lift foreman is skipping this step. When your boat is hauled, you should insist that foreman stop the rig just before the hull clears the water and that he tie the slings together.
The forces that cause the slings to separate are minimal at first. If the slings are properly placed and the boat is successfully hoisted, these forces occur only later when the lift is in horizontal motion, rolling through the yard. Because these forces are slight in the beginning, it only takes a minimal amount of restraint to keep the slings in place. But once they start to separate, the process can accelerate.
Honestly, nothing will happen 99 percent of the time, even without tying the slings together. But there are exceptions, as we saw in the case of the Carver. The slings were not tied, according to a company spokesman, who blamed "wind and water action" for the fall. But it may also be that the boat in the photo was subject to horizontal forces when it was swung, and that those forces aided the slip.
THE RIGHT NUMBER OF STRAPS: Another neglected safety item that shows up in the photo is the number of straps in use. At 55 feet, this was a large hull. Anytime the boat is longer than 35 feet, it is so heavy that using only two slings will create point loads that can damage the hull.
The boat in the photo was about 62,000 pounds, according to the company, meaning each sling was carrying roughly 31,000 pounds. The crane operator will usually check to see that his two straps can support that load with proper margins of safety, but he does not have the background in naval architectural to adequately project how a 31,000-pound point load will affect the keel.
This very likely caused a weakening of the keel itself right at the base, so the Carver may have been damaged before it fell. I have seen many new hulls made of glass reinforced plastic with dents in the keel where the straps were placed during the last haul out.
Most travel lifts in the U.S. have a third or fourth strap location on each side of the lifting strong-back. However, adding these extra straps requires the lift to be idle for about 15 minutes before and after your haul. Time is money and that half hour is long enough for the yard to begin moving another boat. Often, they are reluctant to do this "extra" work, even though they may charge you for your boat's "extra" length. So you must insist. For fiberglass boats longer than 35 feet, three straps should be required and for boats longer than 50 feet it should be four. If the boat is wooden, a 30-footer needs three straps and a 40-footer needs four. Wooden boats over 45 feet should not be hauled with straps. Instead, they should be dry docked or hauled on a marine railway.
PROPER BLOCKING AND SUPPORT: When the boat is set on the hard, before the slings are removed, the owner should observe the keel block installation and the setting of supports.
Make sure that each support is chained to the corresponding support on the other side of the boat, so they don't begin a slow shift outward and away from the hull. When people move around on the boat, the movements cause lateral forces that can shift the supports. If they shift far enough, the boat can fall.
Again, many shipyards do not chain supports together unless you insist. In addition, some will only chain the forward supports, arguing that the rear supports can't slip sideways because they are under a horizontal portion of the bilge. But if you have a modified deep vee hull, there is no portion of the bottom that is horizontal, forward or aft.
FOREIGN VERSUS DOMESTIC: If you are hauling out in a foreign country, be aware that the safety practices there may be very different from here. The Carver photos illustrate this well.
The pictures show that two crewmen were onboard for the lift and rode the boat down when it fell (both survived, and only one sustained minor injuries). In the U.S., there would never be anyone on board during a lift, because industrial safety codes do not allow workers to be subject to that kind of danger.
There may be many things that are common practice abroad that make you uncomfortable, so be prepared to hold your ground on items that could impact the vessel's integrity and safety.
Remember, it's your boat in the sling.
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Capt. Alan Hugenot is a naval architect and marine surveyor based in San Francisco, where he operates an 81-foot motor yacht converted from a Navy patrol boat. His column appears here weekly.
RELATED LINKS:
Read the Story of the Falling Carver