The Hovercraft Revolution and Finding the Right Niche for a Technology
In the world of transportation, some technologies may seem to make everything else appear obsolete, whether it concerns airplanes, magnetic levitation or propelling vehicles and craft over a cushion of air. This too seemed to be the case with hovercraft when they exploded onto the scene in the 1950s and 1960s, seemingly providing the ideal solution for both commercial and military applications. Freed from the hindrances of needing a solid surface to travel upon, or a deep enough body of water to rest in, hovercraft gave all the impressions of combining the advantages of aircraft, ships and wheeled vehicles.
Yet even though for decades massive passenger and car-carrying hovercraft roared across busy waterways like the Channel between England & mainland Europe, they would quietly vanish again, along with their main competition in the form of super fast passenger catamarans. Along the English Channel the construction of the Channel Tunnel was a major factor here, along with economical considerations that meant a return to conventional ferries. Yet even though one might think that the age of hovercraft has ended before it ever truly began, the truth may be that hovercraft merely had to find its right niches after a boisterous youth.
An example of this can be found in a recent BBC article, which covers the British Griffon Hoverwork company, which notes more interest in new hovercraft than ever, as well as the continued military interest, and from rescue workers.
Why Hovercraft Were Terrible
Although we often think of hovercraft as something like something modern, they have been something that people have been tinkering around with for hundreds of years, much like airplanes, maglev and so on. These were all rather small-scale, however, and it took until the 20th century for some of the fundamentals got worked out. The addition of the flexible skirt to contain the air in a so-called momentum curtain to raise the hovercraft further off the ground and add robustness when traveling over less gentle terrain proved fundamental, and within a few decades passenger behemoths were making their way across the English Channel, gently carried on cushions of air:
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Yet not all was well. As can be ascertained by the above video, the noise levels were very high, and so was the fuel usage for these large hovercraft. The skirts ended up wearing down much faster than expected, resulting in a need for daily maintenance and replacement of skirt sections. By the 1990s catamaran ferries offered a similar experience as the clunky SR-N4s, while requiring much less maintenance. When the Channel Tunnel opened in 1994, the writing was on the wall for Britain’s passenger hovercraft.
Years before, the high fuel usage and a range of other issues had already ended the dream of hovertrains. These would have done much the same as maglev trains, only without the expensive tracks. Unfortunately these hovertrains uncovered another issue with the air cushion concept. Especially at higher velocities the loss of air from this cushion would increase significantly, while using the environmental air to keep the cushion on pressure becomes harder, not unlike with the air intakes of airplanes.
Ultimately these issues caught up, with the hovertrain’s swansong occurring in the 1970s with the Aérotrain I-80 and UTACV already. The world’s largest commercial hovercraft – the SR.N4 – made its final trip in 2000 when its operator coasted on for a few more years with its catamaran ferries before closing up shop. These days the only way you can see these artefacts from the Age of Hover is in museums, with the GH-2007 Princess Anne SR.N4 as the last remaining example of its kind at the Hovercraft Museum in Lee-on-the-Solent in Hampshire.
Recently the Tim Traveller YouTube channel went over to this museum to have a gander:
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Why Hovercraft Are Great
So with that said, obviously hovercraft and its kin were all investigated, prodded & poked and found to be clearly wanting by the 1990s, before the whole idea was binned as clearly daft and bereft of reason. While this might be true for massive passenger hovercraft and hovertrains, the reality for other niches is far less bleak. Especially with the shift from the old-school, inefficient engines to modern-day engines, and more of a need for smaller craft.
Currently passenger hovercraft services are quite limited, with the Japanese city of Oita having a hovercraft service between the city center and the airport. Here hovercraft make sense as they are over twice as fast on the 33 kilometer route as the bus service. These hovercraft are built by British hovercraft company Griffon Hoverwork Ltd., as currently the only company building such craft in the world. Similarly, the Isle of Wight’s Hovertravel is a hovercraft passenger service between the island and the mainland, with two Griffon 12000TD hovercraft providing the fastest possible way for people (including many tourists) to travel. Hovertravel’s services are also chartered on occasion with events.
For these tourism-oriented applications the benefits of hovercraft are clear: they are the fastest way to travel especially across water (74 km/h for the 12000TD) and are rather flexible so that they can be used ad-hoc with events that do not have more than a patch of concrete or grass bordering the water. Noise levels with modern engines and with smaller craft are also significantly more manageable.
As addressed in the earlier referenced BBC article, there are three other niches where hovercraft have found a warm home. These include hobbyists who enjoy racing with small hovercraft, as well as rescuers who benefit from having a way to reach people no matter whether they’re stuck on a frozen pond, in a muddy area, in the middle of a swamp or somewhere else that’s hostile to any wheeled or tracked vehicle, never mind rescuers trying to reach someone by foot. Here the property of a hovercraft of not caring much about what exactly its air cushion is pushing against is incomparable and saves many lives.
To Land Where Nobody Has Landed Before
Naturally, the other niche where a hovercraft’s disregard for things like mud, wet sand and rocks is useful is when you are a (military) force trying to carry lots of people, gear and heavy equipment onshore, without such minor details like finding a friendly harbor getting in the way. Although the US Navy and Army had tried to use hovercraft in a more direct role before, such as the unsuccessful SR.N5-derived PACV in Vietnam, their best role was found to be as landing craft: the Landing Craft Air Cushion, or LCAC.
A total of 97 have been built of these LCACs since their introduction in 1986 and they see continuous use as transport of cargo and personnel from ship to shore, across beaches and so on. Due to increasing (weight) demands they are now slated to be replaced by the Ship-to-Shore Connector (SSC). These are very similar to the LCACs, but offer more capacity (~20 ton more), while offering improvements to the engines, the skirt design and a two-person cockpit with fly-by-wire joystick controls.
Similarly, the Chinese Navy (PLAN) also has an LCAC in service (the Jinsha II-class type 726), and both Russia and Hellenic Navy operate formerly Soviet Zubr-class LCACs, which is the largest currently active hovercraft. A few more Zubrs were constructed by Ukraine for both Greece and China, with the latter also building them under license as the Type 958 LCAC.
Happy Niche
Because physics and economics are relentless, hovercraft, maglev and catamarans never made us bid farewell to wheels, tracks, hulls and simple train tracks, but each of these have found their own happy niches to live in. Meanwhile economics change and so does our understanding of materials, propulsion methods and other factors that are relevant to these technologies as they compete with transportation methods that have been a part of human history for much longer already.
For now at least hovercraft seem to have found a couple of niches where their properties provide benefits that are unmatched, whether it’s in simply being the fastest way to move over water, mud and concrete all in one trip, or for the most fun to be had while racing over such a track, or for providing life-saving aid, or to carry heavy loads from ship-to-shore when said shore is muddy marshes, a beach or similar.
Even if we will never see the likes of the Princess Anne again crossing the Channel, the hovercraft is definitely here to stay.
Featured image: Photo of the Solent Flyer hovercraft operated by Hovertravel approaching Ryde (Credit: Geni, Wikimedia)