Stepped Hulls: A Deal With the Devil

Two Decades of Death and Injury. Spin-Out, After Rollover, After Spin-Out

Peter Swanson Jun 14

“Speed is useless without control. Better to build a slower boat with more usable speed.” —Valentine Jenkins, leading figure from “Thunderboat Row.”

Val Jenkins was vice-president for manufacturing at Cigarette, a legendary go-fast company serving racing and consumer markets. Throughout his career, Jenkins refused to build stepped-hull boats for Cigarette’s civilian customers, whom he described as “dentists, doctors and owners of dry cleaners.”

These amateurs were just not serious enough. Their notion of boating was “go fast, look good, get laid,” Jenkins said.

Stepped hulls have tremendous appeal because they make fast boats go even faster without adding horse power. The trade-off has been that many, if not most models can become unstable when turning.

Share

The existence of that deadly flaw was kept quiet in the early days of center-console adoption, according to an industry insider who will be quoted later in the story.

With a handful of notable exceptions, the story of the stepped-hull design is a story about an industry that made a deal with the Devil. The money was good, even as the body-count rose and continues to do so. The cruel irony has been that the dead have often been the bikini-clad companions, not the operators themselves, as the latter survived by clinging tight to the wheel during 65 mph spinouts and rollovers.

At this point, regular readers might be saying, “So what? I’ve got a sailboat, or I’ve got a trawler. We all know the go-fast crowd are a bunch of knuckleheads. Who cares?”

Recent stories about the Bayesian disaster, the loss of the first Pride of Baltimore and a hybrid jetski-pontoon boat that will flip over forward during deceleration weren’t exactly “on market” either, but taken together with this account, they begin to paint a picture.

Boats with design flaws are like mirror-world slot machines. When a certain malign combination of symbols finally displays—call ’em the circumstances—the unwitting players become the opposite of rewarded, whether billionaires on a yacht or a family tooling around Pontoon Lake.

Recent Fatalities

• November 9, 2024: Eytan Genoune, 22, was killed when the Nor-Tech 34 in which he was riding made “an unexpected sudden turn” while traveling southbound on the Intracoastal Waterway near Miami. The turn was violent enough to break off the boat’s T-top and eject all three people on board.
• November 7, 2024: Stephanie Rodriguez, 24, was killed when the Deep Impact Custom 39 in which she was riding, spun out ejecting six of eight occupants after the operator made a turn to starboard. The boat had been traveling from Miami to Key West in a “poker run” event.
• September 26, 2023: Michael Garcia, 41, was killed on Biscayne Bay when Fuel Me Up, the Contender 39 in which he was riding “yawed to starboard and rolled multiple times to port,” ejecting the three men onboard. Garcia was interested in buying the boat, and this was a seatrial. He was at the helm.

All the quoted information above comes from Florida Fish & Wildlife investigation reports. Investigators made no mention of drugs or alcohol being a factor. Each vessel is a center-console with a stepped hull.

Contender is a major American boatbuilder. Loose Cannon emailed the company for comment on the Garcia fatality, referencing Val Jenkins’ position on stepped hulls. There has been no reply.

How They Work

The “steps” molded into a planing hull act as ventilation tunnels, which means they draw air down below the surface of the water. The roiling mix of air and water reduces the friction in the area of the hull behind the step. Reducing friction increases speed and makes for better gas mileage.

The boat’s pivot point, the base of the transom on a conventional deep-V hull, now resides at the step instead, helping to reduce pitching and reduce bow angle, which industry people call the angle of attack. Running flatter means you can see the horizon over the bow.

At this point, Michael Peters should be introduced. He is the naval architect most associated with stepped-hull technology. His first time in a stepped-hull speedboat was with his wife. Peters rolled it and almost killed them both. He went on to develop a stepped-hull safe enough to have been adopted for U.S. Navy fast-attack craft.

Writing in the November 2010 issue of Professional Boatbuilder magazine, Peters highlighted how dangerous unrefined stepped hulls could be compared to conventional deep-V hulls:

A speed, a conventional deep-V runs with its lateral area aft. And, when trimmed in for a turn, the boat adds lateral area and carves a nice, controllable turn. A stepped hull, however, behaves differently. At speed, the wetted surface and lateral area have gaps caused by the steps. The water under the bottom, aft of the steps, is actually an air-and-water mix—there are bubbles—making for very little resistance and a very fast bottom. So when you turn the boat, if you trim in (as with a conventional deep-V), you plant the bow and move all the lateral area forward, with nothing but bubbles—a wetted surface that behaves more like ballbearings…As far as the boat is concerned, there is no drive aft. And therefore no resistance to spinning out and rolling…

We’ve since learned that every manufacturer of stepped hulls has had the same thing happen. Repeatedly. It is the best-kept secret out there.

Hushed-Up

That last paragraph is intriguing. In the early years of the millennia, boatbuilders were taking step-hull technology from the racing teams—whose throttlemen were strapped in and wore helmets—and applying it to center-consoles, which were family and recreational fishing craft.

What Peters was saying, and what he repeated in an interview with Loose Cannon, was that the entire marine industry knew stepped hulls were deadly. Professional Boatbuilder covered the history and proliferation of stepped hulls most thoroughly, but ordinary consumers did not subscribe to Probo, as it was called. It wasn’t on the magazine stands at airports.

The enthusiast magazines—publications read by ordinary boaters—kept quiet about the issue even though stepped hulls were becoming central to a growing number of personal-injury and wrongful-death lawsuits. And, even though, according to Peters, a stepped-hull boat on seatrial actually rolled with bunch of magazine writers aboard!

Not a word was written, presumably because a potential advertiser was involved. By March 2014 Soundings—the newsiest of the boating magazines—was writing about the stepped-hull trend, and although the story buried the lead (as editors like to say), it did include a couple oblique references to the carnage.

A quarter century has passed since the early stepped hulls were introduced to recreational craft and a decade since Soundings leaked its grain of truth. Today, the center-console market is booming in harmony with the near perfection of the outboard motor.

Jenkins and other experts interviewed for this article argue that the behavior of unrefined stepped hulls is too unpredictable for your average weekend boater to master. Going back to the slot-machine analogy, there are several factors on a continuum that are always combining to affect performance as their values change: Speed, trim angle, sea state, weight (fuel in tanks), weight distribution, rate of turn, etc. The number of possible combinations is mind-boggling.

Refinements

Some builders are selling stepped-hull boats that aren’t much improved at all. Others have steadfastly refused to put steps in their hulls, saying their boats were fast enough already. Time has normalized the idea of steps even though the accidents continue.

Some of these stepped-hull boats are much better than they used to be, however. As mentioned, Michael Peters came up with an innovation that largely prevented his stepped-hull designs from spinning out, though he will remind you that spinouts are never impossible given the high speeds involved.

Peter’s refinement was to add another indented section running longitudinally connecting the aftmost step to an opening at the transom. This shallow box-like indentation was inspired by the racing powercat pontoon architecture. This “tunnel” presented just enough lateral area “to catch the hull, but not so abruptly that it will trip it,” Peters told Soundings.

Peters is not a boatbuilder. He founded Michael Peters Yacht Design of Sarasota, Florida in 1981, specializing in high-speed watercraft. Peters designs boats for builders and governments. He won’t license his patented stepped hull to third parties.

His stepped-hull designs are sold by several center-console brands, including Invincible, Blackfin, Valhalla, Barker, Mag Bay and Caymas.

(According to Peters, Contender asked him to design its first stepped hulls, but a contract with a competing builder precluded him from doing so. Had things gone differently, Michael Garcia might be alive today and tooling around Biscayne Bay in a newly purchased Contender 39.)

The U.S. Navy’s Special Warfare Command contracted Peters to draw the lines for its MK VI Patrol Boat, a 61-foot stepped-hull design. Yes, Navy Seals ride into combat on a Peters hull, considered too valuable to die in a boating accident before they can get to the fight. (This story is part of an Invincible Boats YouTube video at bottom.)

SeaVee

SeaVee has been building center-consoles in South Florida since 1974. At around the same time that Peters was working toward his ventillated tunnel refinement, SeaVee decided to come up with its own solution and hired a naval architect named Robert Kaidy as vice-president of engineering.

Where Peters’ solution had been to incorporate an “inny” feature, Kaidy found similar results from an “outy.” That is, a series of strakes, which SeaVee dubbed a “Speedrail.” Thus, declared SeaVee, the stepped-hull was “perfected.”

According to SeaVee, its Speedrail “creates a vertical positive pressure surfaces that does not allow the boat to ‘slip out’ at right speeds or going into a turn.” AI wasn’t a thing 12 years ago, when SeaVee applied for its patent, but there was such a thing as computer modeling. SeaVee went further, as shown below.

At the time, SeaVee produced a marketing video documenting the company’s philosophy and the design process that produced it’s Z Series line of stepped-hull center-consoles, which you can watch below.

Armchair experts may view both of these refinements as obvious. As Peters pointed out, however, the history of invention is full of products or methods that, while obvious in hindsight, represented a huge investment in time, money and human energy during development—in his case, an entire career.

The fact that both solutions are patented means that any other builder who wants to refine its stepped hull to make it safer has to come up with something distinct from the Peters tunnel or the Kaidy strakes.

Or that builder can wait until the patents expire.

SeaVee’s Speedrail patent does not expire until 2034, but the expiration for one of the Peters stepped-hull patents is just around the corner—July 1, 2028. Loose Cannon asked Peters to channel his inner Gandhi. Would he consider releasing his patent for general use early, you know, for the public good? He chuckled and said something about “un-American.”

Training

The U.S. Coast Guard does not have standards for center-console hull designs. The International Organization for Standardization, or ISO, has language on hull construction but not design. The American Boat & Yacht Council, or ABYC, sets standards for many facets of boat construction, but not hull design.

The courts have been handling lawsuits over stepped hulls ever since their introduction into center-consoles, but these proceedings aren’t advertised and attracted little or no attention. You’ve already read how the marine press responded to stepped-hull disasters; this institution is even more lame today than it was then.

So, buyer beware. Anyone with good enough credit can buy a boat that goes over 70 mph and just might rollover under circumstances that are difficult to predict. The only institution that is protecting the public appears to be the insurance industry, which is actually protecting itself.

Some insurers are requiring go-fast buyers to present a certificate from a training organization. The primary motivator may not be as much about hull design as the fact that there are, say, four 450-horsepower outboards attached to the transom of an applicant’s boat. Nevertheless, guys like Tres Martin include lessons in stepped-hull operation in their curriculums.

Martin was an accomplished “throttleman” from the same go-fast culture as Val Jenkins. Back when actor Don Johnson ruled the airwaves playing the lead on “Miami Vice,” Martin was ruling the actual waves of offshore racing, winning multiple world championships. He reinvented himself as a teacher when he founded Tres Martin Performance Boat School in 2004.

He and two other instructors teach 70 to 90 people a year. The courses cost between $2,000 and $3,600 for multiple days of instruction, including time on the water on a customer’s own boat. One of the most difficult parts of the job, Martin said, is telling a student that he or she had failed the course and they would not be getting the certificate needed to obtain insurance coverage for a boat already bought.

“There’s a lot of boats out there that are stepped bottoms developed by trial and error, not even involving a naval architect,” Martin said, acknowledging that some designs are still potentially dangerous. “All I’m here to do is keep people safe. Stepped bottoms are here to stay,” he said.

© 2025 Rio Charters
411 Walnut St. No. 1944, Green Cove Springs, FL 32043
Unsubscribe