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Sea-trialing a displacement hull

The sea trial is your time to find out whether you’re buying the boat of your dreams — or something else.

The sea trial is your time to find out whether you’re buying the boat of your dreams — or something else. What you do and how much you accomplish on the sea trial will depend to some extent on the type of boat you’re testing. And what I cover in this piece should be regarded as only basic guidelines for the minimum amount of testing and scrutiny for most displacement boats. Unless you’re quite experienced, I recommend you take a qualified surveyor on board when sea trialing a displacement hull.

Ground rules

  Read the other story in this package: Sea trials - Putting a boat through its paces      

Establish ground rules before you begin. Your sales contract should spell out risk of loss, which normally will still be with the seller. The seller — or his or her agent — will have ultimate authority over operation of the boat. But within the bounds of safety, prudent seamanship, and simply being reasonable, you should be able to satisfy yourself on all relevant issues.

Take the time you need. Normally you will have put down a deposit as well as signed on the line, and your right to due diligence should be respected. Don’t be pressured by a “busy” broker or seller.

Force yourself to focus on your purpose and to be objective. You’ve been lusting after this boat; that’s why you signed the deal. Don’t let the excitement of the day distract you.

Prepare a personal checklist and stick to it. Circumstances may prevent you from checking out everything you want, but do the best you can. You probably won’t have another chance with the boat.

If at all possible, insist on meaningful sea conditions. Go on a day when you can run in open water that’s reasonably rough, though not unsafe, and also run in protected water. It isn’t going to be a very meaningful sea trial unless you do.

Simulate your future aboard

While away from the dock, try out the things that you’ll want to be doing with the boat. Be imaginative.

Reality check — Lie down in the bunks while at cruising speed to see if you can sleep. Sit on the head and see if you (and the contents of the bowl) become airborne when the boat falls off a wave. Can you take a shower without getting the toilet paper wet?

Examine the boat with a critical eye. Can you cook in the galley while under way? Can you carry food from the galley to the steering station without desecrating that lush carpeting that looked so good at the boat show? Do you smell the bilge sloshing as the boat moves through the water? Can you lay out, study and use a paper chart at the wheel while under way? If you fish, will you be able to bring ’em aboard? Can you walk around the decks easily and safely, both under way and at the dock? (Don’t try this if there’s any question.) Are handholds well placed? Can you go up to and down from the flybridge safely? If your use will be limited to inshore, are you paying extra bucks for a boat specifically designed and built to make ocean passages, and do you want to pay for that feature?

Anchor in deep water and where there’s a chop. It’s amazing how many boats are built with poor anchoring gear. Will the windlass pull up the anchor and chain from deep water? Will it take a week to do it? Does the foredeck layout make you prone to entangle toes and fingers in the rode? Is there a good fairlead for the rode and snubbing gear?

If you plan to anchor overnight, see how well the boat rides on the hook. Some boats sail wildly from side to side, jerking up short on the rode at each end of the swing. Go below while at anchor and see what it feels like in real-life conditions. Can you stand? Will you throw up? Lie down where you’ll be sleeping. Is the slap of the waves on the hull so loud that you’ll be awake all night? Do the tanks slosh loudly? Is the generator noise at an acceptable level so that you can talk and live normally at anchor before you turn it off for the night? Do as much real-world testing as you can in this short period of time.

Ease of repairs — This is important. Check out the accessibility of components that may need to be repaired. As we know, all components on a boat eventually will break. Even if it’s your intention to always have your favorite yard take care of things for you, it’s still important that you be able to make repairs at sea. This directly affects your safety. In many instances, if a repair can’t be made on the spot your boat and passengers may be endangered. If you can’t get tools and spare parts to the problem area, you can’t make the repair.

This issue should be addressed while the boat is at the dock, but you’ll see a new perspective while you’re running. Standing beside an engine on a stable platform is vastly different from standing next to a hot exhaust manifold, rolling around and with nothing safe to hold onto.

Tender test — If the boat has a tender you should launch, run and retrieve it. Insist on this at sea, not just at the dock. We’ve gotten a certain amount of perverse pleasure (the best kind) over the years watching the consternation on the faces of new owners of multimillion-dollar yachts as they try to launch tenders down the sides of their floating condos. On the way down the tender sways out as the boat rolls, then swings back in and slams into the hull — again and again. On one occasion a tender slammed into a stainless steel stanchion, which crumpled and left a jagged end and an obscene SWOOSH as the expensive inflatable suddenly assumed the shape of a well-used balloon.

Feel her

A well-designed boat should be seakindly. See how she handles and rides at different speeds and different angles to the waves. The owner may tell you she’s going to roll like a pig with waves abeam (most unstabilized boats do), but you need to know how bad that pig rolls. It’s also critical to run her down-sea. More than a few boats are a handful in a following or quartering sea, but it’s important to learn whether she’s going to have a tendency to broach or worse, and how well she’ll respond to helm with a stern sea.

Unless you’re able to handle the particular boat well, you may need to have the owner or captain do this so that you’ll all come back alive. Don’t take chances. Also, put her on a straight course, take your hands off the wheel, and let her run. See if she maintains a reasonably straight course in calm conditions without assistance from you or the autopilot. This says a lot about the hull design and underbody configuration.

Running into the sea or with it just off the bow can educate you as to how wet the boat will be. If the spray is coming into the helm station area, think what it will be like in really bad weather. See if it’s coming into the ports and saloon windows. Also, try to assess windage. This will be important in storms under way, at anchor and while maneuvering. Putting her in neutral while it’s blowing and watching what happens will give you some idea of whether your powerboat is really a sailboat in disguise, or whether your sailboat really doesn’t need sails.

Check how the boat performs making sharp turns and maneuvering in tight quarters. The seller probably won’t be overjoyed if you practice maneuvering in the marina, but you can do this in open water with imaginary boundaries. Check the thrusters. Some do poorly against wind or current because they are underpowered or installed poorly. Find out how she handles backing down. With twin-engine boats this usually isn’t an issue, but it can be a significant issue with a single screw. When you’re shifting, listen for any unusual sounds or vibrations, and see if the throttle and shift controls are placed where they’re easy and intuitive to operate. If there is a tank-shifting valve (as with day tanks), see if this works without killing the engine.

Inherent in all of this is the question: How does she feel? This important criterion is very subjective, and the more you’ve handled boats the better you’ll be able to evaluate the feel of this one. Look for things like sluggishness, poor response to power and rudder, too much rolling, top-heaviness, performance while accelerating from slow to high speeds, turning radius, and her ability to reverse momentum — as when you realize the dock is about 200 feet closer than you thought it was.

How is she built?

Get beneath the surface glitz, and bells and whistles while at sea. You and/or your surveyor will have done this at the dock, but to the extent that it’s practical and safe you should also do it while under way. Often things show up at sea that don’t at the dock.

Be sensitive to anything that indicates how well the boat is built and, if it’s used, how it has been maintained. With the vessel running at speed and in a sea, go below and look at flat hull panels. Are they flexing? Pay particular attention to flat panels forward and amidships. Put your hand on them. Do you feel movement? Put your hand on joints between the bulkhead and hull panels to check for movement.

While the boat is under way at speed — if a sailboat, with a fair amount of wind — check to see if hatches, lockers, and doors close and remain closed. Typically sailboat hulls must sustain very different stresses than powerboat hulls because of the opposing forces of the mast step and the standing rigging, as affected by the lateral forces of the wind. Separation of seams in cabinetry or movement of woodwork could indicate poor construction or other problems.

Check for leaks in the hull-to-deck joint, particularly on a sailboat and, if you are in enough sea (unlikely), also in a powerboat. Even a small amount of moisture at hull-to-deck joints can herald trouble.

If possible, walk about the boat while at anchor with the engines off and a sea running, and listen for creaks. Also listen carefully while you are running. The noise of the engine will blanket many sounds, but if you place your ear against bulkheads or hull sections you may be able to hear potential problems. If something doesn’t sound right, it probably isn’t. Beware of dangerous moving parts when you do this.

Look for flex, particularly in the hull around the rudder post, V strut and shaft log. Place your hand on the hull in these areas. (Be careful of moving machinery.) Also take a look at the propeller shaft and stuffing box. The latter usually is inserted into a flexible tube attached to the shaft log. If the stuffing box is jumping about while under way or if the shaft is whipping, it could indicate a faulty prop, misalignment or a problem with the strut. All boats flex to some extent, but depending upon the size, hull material and sea conditions, this shouldn’t be very noticeable.

While you’re conducting your inspection, be sensitive to vibration. Of course, there will always be vibration when an engine is running, but excessive vibration can indicate such problems as poor shaft alignment, untrue prop, and worn cutless bearings. Other trouble signs are unusual vibration when shifting, or resonating or pulsing vibrations, which could point to misalignment, an internal engine problem or a propeller shaft problem caused by a flexing hull.

Sailboat issues

Sailboats have special issues in addition to all the other issues with displacement hulls. These include standing and running rigging, hull/keel joint, mast step, chain plates and how the rudder is hung. While issues such as these should be addressed by a good surveyor and rigging expert at the dock or on the hard, they also should be considered at sea.

For example, while stress is being applied to chain plates (as when you’re sailing off a moderately strong breeze), check to see how well the plate/hull joint is taking the strain. Is there excessive movement? Also, check the hull around the rudder for excessive flex and, most importantly, the hull/keel joint if there is one. Any keel that’s bolted on should be checked thoroughly, with as much stress from sailing off the wind as you can safely apply. This is the time you’re most likely to detect seepage. Place your hand around the hull surface through which the bolts protrude, and check for movement. With a bolt-on keel or even internal lead keel, place your hands on the turn of the bilge sections that take the major stress from the keel. Do you feel movement or flex?

Of course, you’ll want to put her through all the paces on different sail trims and determine how well she sails at all angles to the wind and sea, whether she’s too tender, and how she responds to helm. But forget being a “good sailor” for a few minutes. Put her on a comfortable reach, turn off the autopilot, and take your hands off the wheel. A well-balanced boat should be able to sail herself for a while at appropriate angles to the wind. Sea or changes in wind direction may deflect her course, but give her a chance to show you what she can do on her own. While sailing, spend some time below. Are the fiddles high enough? Does water back up into the sinks when you’re heeling? Check it all out.

Bottom line is safety

While I haven’t specifically talked about safety, most of these points relate to the subject to some degree. Throughout the sea trial, safety issues should be paramount. While you should always have this in mind, most of us need a qualified surveyor on board who is well-versed in all safety issues.

Most people don’t have the experience or training to adequately examine a boat as to wiring, construction techniques, past damage, compliance with standards (such as those of the American Boat and Yacht Council) and many other issues. Unless it’s a small, simple boat and/or you are sufficiently knowledgeable, you should have a qualified surveyor aboard for reasons of safety, as well as to help with all the other issues mentioned. Even if you think you can survey it yourself, your insurance or finance company is likely to think differently. Your surveyor probably will have already inspected the vessel at the dock, but he or she also can be of immense help under way. (The sea trial may not be part of the pre-purchase survey.)

Beware the risks

Much of what I’ve covered here involves risk of injury or property damage. You’re putting a boat through its paces. You’re not familiar with the boat or its condition. Don’t do any of this unless you’re aware of and willing to assume those risks. If you’re not, sit back and let your qualified surveyor and/or a captain do the checking and testing. It’s the job of surveyors and captains to know what they’re doing, and the expense of a surveyor should be worth every penny.

If your sea trial is conducted just as a fun boat ride, it may be the only fun you’ll ever have on the boat. Work hard at it so that you’ll have all the fun you want later.