The answers to your questions are compiled under the guidance of DiscoverHover founder and Chairman, Chris Fitzgerald, who is President of Neoteric Hovercraft, Inc., the world's original light hovercraft manufacturer. Mr. Fitzgerald also founded the Hoverclub of America and is a major organizer of hovercraft events. In addition, he was a participant in the World's First Hovercraft Race in 1960, served as judge in the Learning Channel's Junkyard Wars Hovercraft episode, and is co-author of two books about hovercraft.
What
is a hovercraft?
A hovercraft is one of the children of the air cushion vehicle (ACV) family that flies above the earth's surface on a cushion of air. It is powered by an engine that provides both the lift cushion and the thrust for forward or reverse movement. The hovercraft child is a true multi-terrain, year-round vehicle that can easily make the transition from land to water because it slides on a cushion of air with the hovercraft skirt and only slightly brushes the surface.
In its simplest form, a hovercraft is composed of a hull that can float in water and is carried on a cushion of air retained by a flexible 'skirt'. The air cushion (or bubble), trapped between the hull and the surface of the earth by the skirt, acts as a lubricant and provides the ability to fly or slide over a variety of surfaces.
Hovercraft are boat-like vehicles, but they are much more than just a boat, because they can travel over not only water, but grass, ice, mud, sand, snow and swamp as well.
Is the correct spelling hovercraft,
hovercrafts, hover craft
or hover crafts?
Even though you may see it spelled hovercrafts, hover craft, hover crafts, or even hoovercraft, there is only ONE correct spelling: hovercraft - whether singular or plural. You may have one hovercraft or you may have twelve hovercraft. It follows the same rule as the word aircraft: You may have one aircraft or twelve aircraft, but you never have any aircrafts, air craft or air crafts. Other names sometimes used for hovercraft are air cushion vehicles, ground effect machines/vehicles, surface skimmers, or skimmers.
Why do you believe hovercraft are necessary?
Their unique abilities make hovercraft extremely useful. Hovercraft can fly smoothly over land; still or swift water; shallow, flooded or frozen rivers; sandbars; swamps; snow; and thin or broken ice, giving us access to areas that can't be reached with other vehicles. Their high speed amphibious capabilities are little affected by the movement or the depth of water, or whether or not it is frozen. And hovercraft are safer and more fuel-efficient than boats. In search and rescue operations, hovercraft keep first responders above the danger – not in it - because they safely hover 9 inches above the surface, and can save victims that a boat or helicopter can't reach.
Who invented the hovercraft?
During the 1950s, an Englishman by the name of Christopher Cockerell developed and patented the first official hovercraft. For his contribution to the British people and the Queen, he was knighted and named "Sir" Christopher Cockerell. Soon after, British Hovercraft Corporation developed the first commercial hovercraft for passenger transport across the English Channel. With the ability to carry up to 400 passengers and 50 automobiles, these passenger hovercraft have operated since 1968 and have carried more than 30 million passengers.
The hovercraft concept, however, can be traced back to the early 1700's, and ideas for flying machines date back to ancient Greece. For a comprehensive history of the hovercraft, see History of the Hovercraft
How fast can a hovercraft go? Are they faster on land than on water, or does the surface affect the speed?
Both the terrain and the weather affect the speed of a hovercraft. There is less friction on smooth surfaces, such as ice, so a hovercraft is faster on ice than it is, for instance, on dense grass or rough surfaces. A hovercraft operating on water is affected by the roughness of the water - it will travel faster over smooth water than over waves. In addition, a hovercraft will travel faster when traveling downwind than it will when it faces a headwind. Depending upon the terrain and the weather, the average speed of a hovercraft is 35 mph (56 km/h). Today's light recreational hovercraft can reach speeds in excess of 70 mph (112 km/h).
What is the Hovercraft World Speed Record?
Bob Windt, a member of the DiscoverHover advisory board and designer of the DiscoverHover One hovercraft, holds the Guinness Hovercraft World Speed Record of 85.376 mph (137.40 km/h), which he achieved in 1995 on the Rio Douro River in Peso da Regua, Portugal. A former aeronautical engineer at McDonnell Douglas, Mr. Windt is considered by the Learning Channel's Junkyard Wars to be "the godfather of personal hovercraft."
In hovercraft racing, what is an "Entry Level" hovercraft?
An Entry Level hovercraft is a low cost vehicle constructed with the use of a set of hovercraft plans provided free by DiscoverHover to schools and youth organizations. It is powered by one or more unmodified 4-cycle engine(s) with a total output that does not exceed 12-1/2 hp (9.3 Kw) and can reach speeds of up to 40 mph. For complete DiscoverHover hovercraft engine requirements, see The Hovercraft Engine
Do you consider WIG (wing-in-ground effect) vehicles to be hovercraft?
Yes, the WIG is, in fact, a hovercraft. It is a member the family of air cushion vehicles, which also includes side wall hovercraft, surface effect ships, ram wings, air-bearings and levapads. Check the Air Cushion Vehicle Family Tree on the Neoteric Hovercraft web site.
Do hovercraft hurt the environment?
No. The unique characteristics of the hovercraft make it one of the most environmentally friendly vehicles in the world. One of these characteristics is the hovercraft's low "footprint pressure." The pressure a hovercraft exerts on its operating surface is conservatively 1/30th that of the human foot! The average human being standing on ground exerts a pressure of about 3 lb per square inch (20 KPa), and that increases to 25 lb per square inch (172 KPa) when walking. In contrast, the average hovercraft exerts a pressure of only 0.33 lb (2.2 KPa) per square inch - even less as speed increases. This "footprint pressure" is below that of a seagull standing on one leg! Hovercraft have literally flown over a pedestrian without inflicting harm.
What is a hovercraft hull made of?
A hovercraft hull is typically constructed from aluminum, fiberglass, plastic or plywood, or a combination thereof. Some racing hovercraft have been made from composite honeycomb sheet aluminum. It is important that a provision be made for buoyancy so the craft will float on water. This is usually done by installing urethane or styrene foam inside the hull.
What is the skirt made of?
A hovercraft skirt is made from a flexible waterproof material such as neoprene-coated nylon.
The skirt is one of the most important parts of a hovercraft because it allows the hovercraft to clear obstacles: the higher the skirt, the larger the obstacle that the hovercraft will clear. However, if the skirt is too tall, the hovercraft will 'slide off' the cushion and the cushion will deflate; the craft will become extremely unstable.
There are several types of hovercraft skirts, but the most common are the bag skirt, the segmented skirt and the jupe skirt. The bag skirt consists of a tube that encircles the hovercraft's perimeter. The segmented skirt, also called a 'finger skirt', consists of several separate nylon segments that press together when inflated. The jupe skirt, also called a 'cell skirt', consists of several cells that look like cones with their tops cut off, with their bases attached to the bottom of the hovercraft with breakaway plastic wire ties.
What is the lift system?
Fans generate air pressure that lifts a hovercraft. Fans inflate the cushion contained within the skirt beneath the hovercraft to provide lift and they also provide thrust, which propels the craft forward. Two types of lift systems can be used to provide the air for the lift cushion. Some hovercraft use a separate engine driven fan at the front of the craft, while many craft use some of the air from the propulsion fan, which is ducted under the craft. The latter method is called an integrated system.
A hovercraft can use as many fans as the designer wishes. Most recreational light hovercraft use the single fan or dual fan design. Many large military and commercial hovercraft often use as many as six lift fans and two thrust fans.
What is the propulsion system?
A hovercraft is propelled forward by fan(s) or propeller(s) running in specially shaped ducts. The fans are engine driven via a belt and pulley system or a gearbox.
What type of engines are used in hovercraft?
Many different engines have been tried over the years, but the main requirement has been to get a good horsepower to weight ratio – the engine must be powerful, but light. The 4-cycle lawn mower type engine works well for smaller hovercraft. Compared to a 2-stroke engine, they're quieter and don't require a special fuel-oil mix.
Larger commercial and military hovercraft may use as many as 6 or 8 engines, ranging from diesel engines to jet turbine engines that put out thousands of horsepower.
How big and heavy are hovercraft?
Small single engine craft are around 10 ft (3.048 m) long by 6 ft (1.828 m) wide, and can weigh as little as 100-200 lb (45.5-91 kg). Hovercraft designed for use in industrial, rescue, and military applications are often more than one hundred feet long and weigh many tons.
What is the gas mileage of a hovercraft?
As with most vehicles, the mileage is affected by climatic conditions and the way in which it is driven. On a small recreational hovercraft, you can expect the gas mileage to be as little as 2-3 gallons per hour (7.6-11.4 liters per hour).
How does the average fuel consumption of a hovercraft compare to that of a car and a boat?
It is not very helpful trying to compare the amount of fuel various vehicles use in order to see which is the more efficient. There are efficiency formulas which can compare different transport vehicles, and one of the most famous compares "the amount of weight moved over a distance divided by time". Because distance divided by time is speed, the efficiency becomes weight moved by speed. Now, if you divide by the energy required to move the weight at a certain speed, you have one method for comparing various transportation means.
Just for kicks and giggles, the average car uses about 3.2 US gal/hour. A similar sized hovercraft uses about 2.8 US gal/hour and an equivalent boat uses about 5 US gal/hour. You can see, however, that when wind, waves and the weight carried change then everything becomes much more complicated. When we compare the car with the hovercraft we are doing the same thing as trying to compare chalk with cheese!
Is a hovercraft difficult to drive?
Learning to steer a hovercraft is more like learning to fly a helicopter than learning to drive a car or steer a boat. That's why a person operating a hovercraft is usually referred to as a "pilot" rather than a driver.
As with any motorized vehicle, it takes practice to maneuver a hovercraft. As Sir Christopher Cockerell, the inventor of the hovercraft, explained, "Driving a hovercraft is like driving a car with four flat tyres on ice!" Although at first it might seem impossible to point the craft in the direction you want to go, it doesn't take long to master the principles. The controls are very simple; throttle controls for engines and handlebar or joystick controlling the rudders for steering.
Can you make a hovercraft stop and back up?
Yes, although it requires some mechanical wizardry since no part of the craft is in contact with the ground. Currently, Neoteric Hovercraft, Inc. manufactures the only hovercraft on the market with effective brakes.
Do you need a license to pilot a hovercraft?
No. In the United States, hovercraft come under U.S. Coast Guard jurisdiction and are registered as boats. Some states in the USA may require an ATV license as well. Whether you live in the United States or another country, you should contact your nation's hovercraft federation or marine authority, or your local hovercraft club for current requirements. For links to hovercraft federations and clubs, see DiscoverHover Links.
Where can I use a hovercraft?
There are many areas a hovercraft can be used and enjoyed. Hours of fun can be had on lakes and rivers exploring where no other craft can go, as well as on snow covered fields, frozen lakes, on mud, marshes, and even on the ocean depending on the conditions. Check with local/county authorities on regulations in your area.
You can also participate in established hovercraft races, cruises and Hover Rallies sponsored by hovercraft clubs and the World Hovercraft Organization.
Can a hovercraft be driven on the road?
Road travel is possible, but it isn't recommended. Roads are designed for cars and have a 'camber' – the surface is slightly humped up in the middle to allow water to run off. This causes very unstable driving conditions for hovercraft. Also, the abrasiveness of the road's surface causes excess skirt wear.
What are hovercraft used for?
Hovercraft are so versatile that their applications are as diverse as the people who use them. They are used for recreation, education, racing, rescue, military and a multitude of commercial uses. The major value of hovercraft is they can reach areas that are inaccessible on foot or by conventional vehicles. A partial listing of present uses includes:
- Exploring the vast number of shallow and narrow waterways that cannot be reached by boat
- Rescue work on swift water, ice, snow, mud flats, deserts, in wetlands, shallow water, swamps, bogs, marshes and floodwaters.
- Affordable, safe way to fly without a pilot's license.
- Transport in environmentally sensitive areas where habitat, erosion and soil compaction are a concern
- Wildlife conservation and research
- Transportation or "island-hopping"
- Fishing anywhere ... including ice fishing
- Traveling from land to water where there is no boat dock
- Military services: Assault vehicles and transporting troops
- Dive recovery teams
- Retrieving birds from tailings ponds at mining sites
- Water management
- Border Patrol and Homeland Security
- Port authorities/drug enforcement
- TV and film companies (James Bond movies often use hovercraft)
- Entertainment at Disney World water shows
- Agricultural spraying; cranberry, rice and pecan farming.
- Survey work
- Forestry
- Heavy load movement across difficult surfaces
- Mosquito abatement
- Environmental testing; intertidal zone soil sampling
- Charter operations and passenger ferries
- Oil spill clean up
- "Bird hazing" – chasing geese from lakes in the vicinity of airports
When you were younger did you ever dream of hovercraft-like things?
Hovercraft have been the driving force throughout most of my life. I am old enough to say that I eagerly followed the development of the first fully-functioning hovercraft, invented by Sir Christopher Cockerell in 1958, and looked on from afar as his first passenger craft, the SRN1, flew across the English Channel from France to England in 1960. I was so inspired that, at the age of 14, I decided to try to invent a smaller, more personalized size of hovercraft that would make this mode of flight more accessible. After 13 years of development, my Neova 1 was born.
Why / what made you decide to go into the hovercraft business?
This is something that happened quite by accident. My original thought was that I would be able to sell my invention to an American company so that they could manufacture them, but as it turned out, no one was willing to making a product for which there was no proven market. Remember, this was at a time when no one knew what a hovercraft was or what it might be used for. Therefore, I decided to move from Australia to the United States and start my own hovercraft manufacturing business.
Are you proud of your work with hovercraft? Why or why not?
Yes, I am pleased that I have spent my life developing a product, a market for the product and a means of manufacturing it. It is also gratifying that what I manufacture is so useful, and will continue to grow in its usefulness.
How do you get into the hovercraft business?
This depends on what you wish your level of involvement to be. Do you want to design them, build them, or market them? The best thing you can do is to imagine which part of the business you find most interesting and get a college degree in that. My degree is in engineering since I am the designer. Knowledge is essential.
Also, I would suggest that if you are truly interested in hovercraft, you should join the Hoverclub of America or a hoverclub near you to find out what is happening in the field. There you will read about the latest developments, various types and styles of hovercraft, the experiences of the club’s members, as well as the dates and locations of hover rallies … events that you would find to be both fun and educational.
What would be your advice to someone who would like to get into the hovercraft business?
First, learn everything you can about hovercraft first, including how to pilot one. Immerse yourself. Hopefully this will help you acquire a vision of what it is that you want to do with the business. One warning: many have come and gone in the world of hovercraft manufacturing and sales. Hovercraft are still in their infancy as far as public awareness goes, and so you must be prepared with a long-term goal and the perseverance to make it happen.
Do you consider your job to be work or fun?
This is a difficult question to answer. Sometimes I wonder myself! Having worked incredible hours over the 50 years that I have been at this, I am finally seeing my dream materialize. “Fun” may not be the most accurate word to use … perhaps "satisfying" would be more appropriate. It pleases me greatly to know that what I have believed in all these years is now gaining acceptance, and that people are able to put hovercraft to such good use … even for saving lives.
What do you have to figure out to design a hovercraft?
First of all, you must have a good understanding of engineering. There are various publications and technical papers written on the subject, one of which, Light Hovercraft Design, was co-authored by my partner and me and is available for $30 from the Hoverclub of America.
Do you have a favorite hovercraft? What is it and why?
My favorite hovercraft is the SRN4, due to its brilliant engineering. This hovercraft was the brainchild of a large team of exceptionally bright and unusual engineers. The SRN4 was a true performance machine that could carry nearly 500 passengers at speeds of 65 mph over water. It was quite exhilarating to see the SRN4 raise nine feet off the ground and watch as it slid along the concrete hoverport then out to sea. The SRN4 was a leviathan of the sea.
Did / do you like to watch Star Trek and other sci-fi movies?
Sorry! Star Trek and other sci-fi movies have never interested me. I guess I have spent so much time involved with “Mrs. Hovercraft” that I have created my own universe.
What do you think of the Star Wars hovercraft-like vehicles? Pretty accurate? Possible?
Although the concept of the Star Wars hovercraft may seem nifty, in reality, they are not possible. Without getting overly technical (see the website), the higher off the ground the craft is, the more unstable and difficult to control it becomes. If it gets high enough, it will actually fall over (off-cushion).
In what ways can hovercraft be improved?
The hovercraft industry is still a wide-open area for research and potential breakthroughs. The most important improvements are needed in reduction of necessary maintenance, as well as reduction of noise, spray and dust. Improvements could also be made to help the hovercraft more pilot-friendly.
What do you foresee in the future of hovercraft?
The future of hovercraft is limited only by man’s imagination. I would refer you to our Neoteric Hovercraft, Inc. web site for lists of rescue, commercial and recreational hovercraft uses. Overall, though, the more awareness increases, the bigger and brighter the future of hovercraft will be. At present, the largest number of orders for the Neoteric Hovertrek™ is for rescue hovercraft. Although they are used for everything from border patrol to rescuing flood victims, hovercraft are finally beginning to be recognized as the safest way to rescue someone who has fallen through ice. When you think of how many cities there are, and the need for each to have rescue vehicles, this alone makes the future of hovercraft seem bright, indeed. For more detail, see "The Future of Hovercraft" at the bottom of History of the Hovercraft.
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