What would happen if you crossed a boat with a plane?

If you are looking for a fast and fun way to travel over water … If you ever wondered what would happen if you crossed a boat with a plane, you might be interested in wing-in-ground (WIG) craft/ vessel (I will use them interchangeably as per the context in this paper). A WIG craft is a vehicle that flies close to the surface of the water (or any other flat surface) by using the aerodynamic lift generated by its wing, hull, or both … a phenomenon called ground effect. Ground effect is when the air pressure under a wing increases as it gets closer to the ground, reducing the drag and increasing the lift. This means that a WIG can fly faster and more efficiently than a normal aircraft, but only at low altitudes. It is like a hybrid between a plane and a boat, but much cooler. Think of it as a plane that hugs the water like a dolphin.

Sounds cool, right? Well, not everyone thinks so. The Soviets (those who are newborns :-) may like to read history of Russia and search USSR) experimented with these sea monsters for decades, but they never really caught on. Maybe because they looked like giant ducks or flying whales. Or maybe because they were too big, too noisy, or too scary for the rest of the world. WIG crafts have been around for decades, mostly in experimental military use, but they are becoming more popular and accessible thanks to the guidelines issued by the International Maritime Organization (IMO) in 2018. There are different types of WIG crafts, depending on how high they can fly above the ground effect. Ground effect is the phenomenon that reduces the drag on a wing when it is close to a surface, such as water.

The history of WIG crafts is fascinating and full of innovation. The concept of WIG craft was first explored by German engineer Alexander Lippisch in the 1920s and 1930s. He designed several experimental models, such as the X-112 and the X-113, that demonstrated the feasibility of WIG flight. The first WIG craft was designed by Finnish engineer Toivo Kaario in 1935, but it never flew. The most famous WIG craft was the Soviet ekranoplan, which means “screen gliders” in Russian. One of them was so huge that it was nicknamed the Caspian Sea Monster by CIA analysts who saw it on satellite photos. It was larger than any plane they knew of, and could carry up to 500 tons of cargo or weapons. It was also nuclear powered, because why not? Caspian Sea Monster was a huge vehicle that could carry up to 544 passengers and reach speeds of up to 500 km/h. It was built in 1966 and crashed in 1980. Other countries that have developed WIG crafts include Germany, China, Japan, South Korea, Australia, and the United States.

cnn.com

Despite their dubious past, WIG vessels may have a bright future. I believe that they could be used for efficient and fast freight transport, especially in remote areas where infrastructure is lacking. They could also be used for tourism, recreation, search and rescue, or military applications. Imagine flying over the ocean at 200 km/h, enjoying the scenery and the breeze, while avoiding pirates, storms and traffic jams. Sounds like a dream come true, right? Well, maybe not for everyone. Some people might find them too risky, too expensive, or too ugly to ride. But hey, beauty is in the eye of the beholder! There is a potential for WIG vessels to become a more common mode of sustainable transportation of the future. For example: WIG craft have the potential to revolutionize the transportation industry by offering faster delivery than a container ship and at a fraction of the price of commercial airfreight, where fuel cost is a very dominant factor. WIG vessel carrying freight could operate between networks of coastal airports spread across the Asia-Pacific region . Despite the challenges associated with WIG vessels, such as the requirement for a relatively flat surface to operate, there are several advantages to using WIG vessels for certain types of cargo. As the technology continues to develop and the regulatory framework evolves, I see a definite possiblity that WIG vessels will become a more common sight on the world’s waterways.

WIG vessels have a unique architecture that combines elements of maritime and aviation design. WIGs can vary in size and shape, from small recreational vehicles to massive military machines. They have wings, but they are short and stubby compared to normal planes. They have hulls, but they are shaped to create stagnation air underneath them when flying close to the surface. They may also have pontoons, water skis or hydrofoils to help them take off and land on water. Some of them even have auxiliary engines to blow air under the wing and create more lift. Talk about overkill! :-)

Typical architecture of a wing-in-ground effect vessel is based on the following principles:

· Wing-in-ground effect: The phenomenon of increased lift and reduced drag when a wing operates close to a surface, such as water or land. This allows the vessel to fly at low altitude with high efficiency and speed.

· Wing configuration: The shape and arrangement of the wings that generate the lift and control the stability of the vessel. There are different types of wing configurations, such as tandem, canard, box-wing, blended-wing-body, etc.

· Hull design: The shape and structure of the main body of the vessel that houses the payload, crew, engines, and other systems. The hull design should be compatible with the wing configuration and the operational mode of the vessel. The hull may also have a boat-like shape to provide buoyancy and water displacement.

· Propulsion system: The type and location of the engines that provide the thrust and power for the vessel. The propulsion system should be suitable for the performance and maneuverability requirements of the vessel. The propulsion system may also include auxiliary engines or fans to assist the take-off and landing of the vessel.

· Landing gear: The devices that enable the vessel to take-off and land on different surfaces, such as water, land, or ice. The landing gear may include skis, wheels, floats, or hydrofoils. The landing gear should be retractable or detachable to reduce drag and weight during flight.

Beauty of WIG vessel is that it is a type of craft which is supported in its main operational mode solely by aerodynamic forces which enable it to operate at low altitude above the sea surface but out of direct contact with that surface . They are multimodal i.e. in their main operational mode, fly by using ground effect above the water or some other surface, without constant contact with such a surface and supported in the air, mainly, by an aerodynamic lift generated on a wing (wings), hull, or their parts, which are intended to utilize the ground effect action . The arrangement, engineering characteristics, design, construction and operation of WIG vessels have a high degree of commonality with those characteristics of aircraft . A WIG uses the aerodynamic effect of ground effect to achieve high speed and fuel efficiency.

The design of a WIG vessel involves several challenges, such as stability, control, propulsion, and safety. I will briefly describe some of the main aspects of WIG design:

1. One of the most important factors in WIG design is the shape and size of the wing. The wing should have a high aspect ratio, meaning that it is long and narrow, to reduce drag and increase lift. The wing should also have a low angle of attack, meaning that it is slightly tilted upward from the horizontal, to avoid stalling and maintain ground effect. The wing should be positioned close to the water surface, but not too close to avoid splashing and wave interference.

2. Another factor in WIG design is the control system. The control system should provide adequate maneuverability and stability for the WIG vessel, especially at low speeds and during take-off and landing. The control system may include flaps, ailerons, elevators, rudders, or canards, depending on the configuration of the WIG vessel. The control system should also be able to adjust the height of the WIG vessel above the water surface, to optimize the ground effect and avoid obstacles.

3. A third factor in WIG design is the propulsion system. The propulsion system should provide sufficient thrust and power for the WIG vessel to achieve its desired speed and range. The propulsion system may consist of propellers, jet engines, or ducted fans, depending on the performance requirements and noise constraints of the WIG vessel. The propulsion system should also be integrated with the wing structure, to minimize drag and interference.

4. A final factor in WIG design is the safety system. The safety system should ensure that the WIG vessel can operate safely in various weather conditions and emergency situations. The safety system may include flotation devices, parachutes, fire extinguishers, or ejector seats, depending on the size and type of the WIG vessel. The safety system should also comply with the relevant regulations and standards for watercraft and aircraft.

Designing WIG vessel involves several steps. Here are some of them:

1. Define the mission profile: This includes determining the payload, range, speed, and operating height of the vessel.

2. Select an appropriate wing configuration: This could be a tandem wing, a canard wing, or a delta wing, that can provide sufficient lift and stability in ground effect.

3. Choose an aerofoil shape: This could be a Clark Y or a NACA 4-digit series, that can optimize the lift-to-drag ratio and reduce the induced drag in ground effect.

4. Estimate the weight and balance of the vessel, taking into account the structural, propulsion, and payload components.

5. Calculate the wing loading, wing area, wing span, and aspect ratio of the vessel, based on the desired take-off and cruise performance.

6. Design the fuselage, empennage, and control surfaces of the vessel, considering the aerodynamic, hydrodynamic, and structural aspects.

7. Select a suitable propulsion system, such as a propeller, a jet engine, or a ducted fan, that can provide enough thrust and efficiency for the vessel.

8. Perform a safety assessment and a stability analysis of the vessel, using analytical, numerical, or experimental methods, to ensure that the vessel can operate safely and reliably in various conditions.

WIG craft are categorized according to the following types :

A. Type A: a craft which is certified for operation only in ground effect. Within prescribed operational limitations, the structure and/or the equipment of such a craft should exclude any technical possibility to exceed the flight altitude over the maximum vertical extent of ground effect.

B. Type B: a craft which is certified for main operation in ground effect and to temporarily increase its altitude outside ground effect to a limited height, but not exceeding 150 m above the surface, in case of emergency and for overcoming obstacles.

C. Type C: a craft which is certified for the same operation as type B; and also for limited operation at altitude exceeding 150 m above the surface, in case of emergency and for overcoming obstacles.

WIG crafts have many advantages over conventional planes and boats. They are more fuel-efficient, faster, safer, and environmentally friendly. They can also operate over any flat area such as frozen lakes or flat plains similar to a hovercraft. Wing-In-Ground vessels could potentially revolutionize the future of transportation in several ways:

· Fast Freight Transportation: WIG vessels could offer faster delivery than a container ship and at a fraction of the price of commercial airfreight. This is particularly beneficial for a segment of the freight transportation market that seeks fast delivery even at premium transportation tariffs.

· Increased Payloads: WIG vessels could potentially carry much greater payloads at lower cost per weight unit or per unit of freight. For instance, high-speed mono-hull hydrofoil vessels are restricted to a maximum weight of 400-tons, which could also be the maximum weight of a hybrid hydrofoil — WIG effect vessel. However, innovation might increase the lift-off weight of WIG vessels.

· Maritime Structural Standards: WIG craft are maritime vessels that would be built to maritime structural standards. The design would include pontoons, water skis, and possibly hydrofoils to allow for touch down on and lift-off from a water surface.

· Operation Between Coastal Airports: WIG craft could operate between networks of coastal airports spread across various regions. This would provide a fast and efficient mode of transportation, particularly for freight services.

· Fuel Efficiency: WIG vessels can cruise close to the ocean surface, which can minimize fuel consumption.

These potential benefits definitely suggest that WIG vessels will play a significant role in the future of transportation, particularly in the freight industry. However, it’s important to note that these are potential benefits and the actual impact will depend on various factors including technological advancements, regulatory frameworks, and market acceptance.

WIG crafts are an exciting and promising mode of transportation that could revolutionize the way we travel over water and air :-). They are not just science fiction, they are real and they are here to stay.