Environmental Impact Of Hovercraft
For any craft to operate in an economical fashion, it’s resistance to motion, or drag, must be kept down. With an automobile, this means having good tires that are properly inflated. With a boat or ship, this means having a good hull design and keeping it clean of growth. With trains, this means level and clear tracks to run on.
With a hovercraft, this means having a nice cushion of air to ride on.
That cushion of air is what makes the hovercraft actually the best choice for environmentally fragile areas. There is no rail, road or shipping channel that must permanently scar the environment and there is no wake from a hull cutting through the water.
Running a stretch of highway or rail would be totally devastating to a fragile ecosystem like most sounds and back water areas. Either of these things are often totally devastating to an ecological system like a sound or a marsh, as well as being financially ludicrous to achieve. Using boats as transportation is also as potentially devastating to an area due to the fact that the vessel has a hull that must usually go under the water requiring dredging of waterways and then the adverse effect of wakes causing changing water levels and erosion. Anyone familiar with boating knows what a “no wake zone” is and why it is there. Shore dwelling animals do not do well when their environment gets flooded and washed away by a boat’s wake.
Because a hovercraft rides on air, not water (or land) it can safely travel through some very environmentally fragile areas with minimal impact. Sure, the animals may not like a hovercraft going directly over head, but that is not in the same arena as a boat which will effect areas many thousands of yards away from their actual path of travel. A hovercraft only effects what is directly under it and then only with a wash of air. This makes it easier to have a negligible impact on an environment by making sure not to pilot the hovercraft directly over an estuary or other type breeding ground.
To put things into contrast, a human standing still exerts about 3 pounds of pressure per square inch, when walking this can go as high as 25 pounds per square inch. The average hovercraft exerts about 0.33 pounds per square inch on the surface, irregardless of whether it is standing still or traveling at full speed. There are birds that produce more pressure per square inch.
Another point to consider in an environmental impact of wetlands is the noise that is produced, both above the surface of the water as well as below. Because a hovercraft has no parts that go under water, there is no direct sound conduction into the water. There is no big noise to scare the fish. The above surface noise is far less than a train and about the same levels as a truck or a bus. Not only is this an obvious statement but it has also been tested by independent scientific methods. As for the above surface level noise, technology has come a long way in making the propeller blades work as efficiently as possible and keeping the noise down. Most of this noise is actually aimed behind the craft due to the nature of how propellers work.
A side benefit of hovercraft in an ecologically sensitive area is that by design necessity the hull of a hovercraft is a sealed unit. This means that should the engines have a leak of some sort, the leak would not escape the craft and “drip” into the environment. There is also no exhaust outlet below the surface like with most conventional water craft. This means that there are no emissions gases being pumped into the water and no change in water temperature.
Another factor with hovercraft is that the engines are very efficient and “clean” due to the nature of the vehicle. Hovercraft tend to use 4 stroke engines where as many conventional marine vehicles use the “dirtier” 2 stroke type of combustion. Conceivably, hovercraft could also use totally “green” propulsion methods and increase their fuel efficiency immeasurable.
As with dredging shipping channels, most marine vessels also require other environmentally impacting modifications to an area, for example: a dock. A hovercraft has not need for any formal docking area. In truth, the only thing a hovercraft needs is the ability for people to get to the craft. A hovercraft could effortlessly travel from open water over grass marsh and pull right on to an existing parking area. This would allow the passengers to embark/disembark without making ANY changes to an environment.
A couple of recent studies in the United Kingdom and Australia (where hovercraft have been used extensively for over 30 years) bear out the above. They found that the hovercraft caused NO damage to sea grasses or invertebrates in inter-tidal areas and that bird life rabidly adjusted to the hovercraft’s presence in their environment.
Hovercraft are without a doubt the most environmentally friendly way for humans to traverse fragile ecosystems.
This isn’t theory, but fact with hard evidence as has been briefly outlined here.