Going with the best-current-ferry flow

Contents
author Cimino
first published 20230628
second edition 20240810

Full Circle: Having instantly won hearts and minds, the design for a purpose-built scow, provisionally named the Mahu, was set aside when what seemed to be a ready-made, built-to-survey vessel became surplus to regional park operations. Now, serious consideration is being given to the above design being realised, sans scuppers, as a purpose-built J Barry Ferguson. design Mahurangi Magazine

Do they know those days are golden?
Build a rocket boys! Build a rocket boys!
Lippy Kids, Guy Garvey

This article began life a year ago, as a best-current-thinking footnote to It’s a barge! It’s a boat! It’s the J Barry Ferguson . Titled Purpose-Designed Flat-Bottomed, the footnote suggested that work-to-date estimating the probable cost of extending the J Barry Ferguson  to 8 metres was tending to confirm the intuition that it could cost as much again as the purchase price. For some time, one member of the team was already of the we-can’t-get-there-from-here persuasion. Then another admitted that he was of increasingly of that view. Consequently, this writer revisited the pre-Park Ranger  concept published in May 2019, pictured here, and rapidly formed the opinion that it would be a far better use of resources.

With any conversion of the Park Ranger , the main design compromise is its greater-than-ultra-shallow draft, and its sticky bottom. For the Mahurangi Coastal Path to be a Mahurangi  Coastal Path, it needs to cross the Mahurangi Harbour. That means embarkation /disembarkationsurely we should have a less cumbersome word—’mbarkation?—for embarking and alighting a vessel or vehicle? in the famously shoal Lagoon Bay, on the remote Mahurangi Peninsula. For most craft, embarkation on a falling tide is impracticable—the combination of extra weight aboard, and less water in which to float. Unsurprisingly, this is not an insurmountable challenge for oyster farmers. Barges with flat bottoms uncompromised by runnersbottom runners, longitudinal strakes to provide directional stability and/or to protect the hull from wear when grounding can be refloated after inadvertent partial—or calculated—groundings with alacrity, while harvesting oysters. With a bit of skill and muscle, some can even be slid back into the tide after being fully stranded, fully laden.

Key attributes, for a barge to be stranding-resistant, are threefold. The bottom must be predominantly flat, to spread the weight over as much mudflat as possible. There must be no protrusions such as keelsons, runners, or rivets. The bottom surface must be of a hard and non-binding material—unlike aluminium, regarding the latter attribute—and preferably self-lubricating. As luck would have it, such a surface exists and can readily be applied to plywood, in the form of epoxy-graphite. And a good amount of plywood is already to hand, purchased to build a shelter for the corrosion-prone aluminium Park Ranger .

A purpose-built J Barry Ferguson  would also have a vastly different bow-ramp configuration. Designed for the embarkation/disembarkation of people, with or without wheelchairs—as opposed to vehiclesmowers, in particular—and where there may be stiff current flowing, bow ramps, plural, are deployed, which allow the craft to be angled to the shore with the shoreward ramp deployed. The raised ramps, meantime, provide a pointy end, rather than a square one. This—New Zealand-scow type, but pointier—allows the craft to steam head on into large seas, safely parting their impact—something that square-bow barges are brutes at doing. Although the largest waves the purpose-built scow would be designed to encounter would be swell-against-tide when exiting the Pūhoi Rivermouth, there would also be many occasions crossing the Mahurangi Harbour where having a sharp scow bow would hugely improve the comfort of those aboard—those who can famously feel motion-sick, at the mere sight of a travel poster.

Importantly, the design of the purpose-built J Barry Ferguson  would incorporate the learnings from the Park Ranger  experience. Rather than the liberally self-draining deck of the 2019 Mahu  design, above, the deck would be set low, à la lca, and its outer edges brought well inboard by built-in seating—to mitigate free-surface-effect. The benches, forming part of liberally buoyant bulwarks, would guarantee great swamped-vessel stability. The net result, in respect to the lower, built-in seating, would be more stability, and less exposure of those seated to windchill. Although the seats would be richly upholstered, to make it abundantly clear they were not to be stood on, the bulwarks would be topped with wire guardrails set so as to discourage sitting atop the otherwise-all-too-appealing bulwarks.

Another feature that the purpose-built J Barry Ferguson  would incorporate, from the extant J Barry Ferguson, would be the side-boarding ports created more recently in to enable rapid, level embarkation/disembarkation from floating docks such as at the Wenderholm Jetty. These would also tick, very decisively, the possibly soon-to-be-regulatory requirement that an unresponsive person be readily recovered from the water.

Myriad other benefits arise from the purpose-design-and-build approach, not least of all a toilet. Although not  required by maritime authorities for short voyages, in the Mahurangi Coastal Path setting, the person embarking may have already been deprived of a toileting opportunity for some time—not to mention the selfless volunteer crew, who will also benefit from more protection from the elements than a mere bimini. Scale, though, is important. The purpose-built J Barry Ferguson could be 12 metres by 3.6 on deck—about two and a half times the sum of those dimensions of the extant craft. This means that the weight of half a dozen—or even a dozen—persons-in-the-wrong-place is not nearly as problematic.

Inherently, and unavoidably, a purpose-built J Barry Ferguson  would be a prototype—a vessel on which to make mistakes and iron out defects. But if it performed as well as it might, during heeling tests and swamped-stability tests, it could lead to a small fleet of such craft being built. A sailing scow along such lines would be make a marvellous, affordable, latter-day mullet boat—one that could be owned, or hired, by a group of young people, with the deck and bench-seat space needed for summer nights slept under boom tents.

 

 

Open-boat speaks volumes That the current regulations use the term open boat  to differentiate between craft such as the J Barry Ferguson  and most decked vessels, speaks volumes. It reflects the fact that, aside from the likes of specialist open vessels such as hopper barges, if a vessel is undecked, the chances are it will be of a size that most people would immediately think boat  rather than vessel  or ship. Boats, however, can be big. Steamboats, such as those that serviced the Mahurangi until the 1930s, can be the size of small ships, and they were very definitely decked. Somewhat more helpfully, it is likely that new regulations will refer to vessels without—or with marginally above-waterline—decks as open vessels, rather than open boats.

 

 

 

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