Throughout the history of navigation and shipbuilding, which historians estimate to be almost 9,000 years old, people have always wanted to travel faster on water. However, the speed of water transport has always lagged behind other modes of transportation. Consider the fact that it takes a satellite 1.5 hours to orbit the Earth. Supersonic aircraft have become commonplace. Trains have surpassed speeds of 300 kilometers per hour. But what about on water? Today's maritime and river transport vessels still move at a speed not much faster than a sailing clipper from the mid-20th century.

Rostislav Evgenievich Alekseyev (1916-1980), a Doctor of Technical Sciences and a recipient of the Lenin and State Prizes, was one of those who managed to solve the problem of accelerating the movement of ships. Viktor Vasilyevich SOKOLOV, who worked under Alekseyev's direct supervision for many years and became the Chief Designer of the ekranoplan program and the Chief Designer of several ekranoplan models, shares his insights on this topic.

The widespread introduction of hydrofoils in the 1960s significantly changed the parameters of passenger transportation by water transport. In the future, SECS were also used in the Armed Forces as small anti-submarine ships and patrol boats.

Static air cushion vessels (SACVs) allowed for a slight increase in top speed compared to SCVs, but they also faced an insurmountable speed barrier of 150-180 km/h due to loss of stability.

Unlike SSVP, ekranoplanes are supported above the surface not by a static (artificially created by special superchargers with corresponding power consumption), but by a natural dynamic air cushion, arising from the speed pressure of the incoming air flow. In this case, there is a so-called screen effect, which consists in increasing the aerodynamic quality of the air wing when it moves near the shielding surface, as well as in its self-stabilization in terms of the height of movement relative to the screen.

The effective movement height of a ekranoplan above the surface is commensurate with the geometric dimensions of the air wing, and the positive effect of the ekran effect increases with decreasing movement height.

Shipbuilders and aircraft manufacturers were working on the practical application of the screen effect. The former were interested in it as a means of increasing the speed of ships, while the latter were interested in it as a means of increasing the fuel efficiency of civilian aircraft and enabling low-altitude flights for military tactical purposes.

The first practical developments of ekranoplanes in our country were carried out by the famous aviation engineer and inventor P.I. Grokhovsky in the second half of the 1930s. However, the main work fell to R.E. Alekseev. Together with the team of the Central Design Bureau for Surface-to-Air Craft, he significantly contributed to the acceleration of scientific and technical progress in the field of high-speed shipbuilding, first by creating hydrofoil vessels and then by developing ekranoplanes. The work on ekranoplanes is the most significant and vivid page of Alekseyev's and the Central Design Bureau for Surface-to-Air Vehicles' creative biography, which is being revealed today.

The aircraft-building organizations and aviation institutes of the Soviet Union made a significant contribution to this new field. The search for a layout solution for the ekranoplan led to the use of a classic aircraft design (single-wing monoplane with a single-point configuration and a tail fin), which was modified to ensure stability and controllability when moving near the shielding surface.

The essence of this modernization was reduced to two main aspects:

- selecting the parameters of the main carrier wing and optimizing its position relative to other layout elements:

- the use of a developed (enlarged) horizontal stabilizer and its positioning in terms of height and length relative to the main wing in such a way that it is least sensitive to changes in the air flow induced by the wing, depending on the altitude of flight and the angle of pitch.

These aspects formed the basis of the concept that determined the final choice of the basic layout of the ekranoplanes, which was adopted for implementation in the early 1970s. Based on this layout, ten experimental ekranoplanes were created, with their size and weight gradually increasing.

The ekranoplan ship-model (KM) in this series was the most significant creation of Alexeyev. Created in the 60s, it had a length of more than 100 meters, a wingspan of about 40 meters, and in a record flight its mass reached 540 tons, which represented at that time an unofficial world record among aircraft, which was broken only by the An-225 "Mriya" aircraft.

Over the course of 15 years, the KM ekranoplan underwent comprehensive testing and completed a cycle of work related to testing the idea of ekranoplanes in general, as well as developing the scientific foundations for their design, construction, and testing. These results allowed for the creation of a theory and methodology for the design and construction of practical ekranoplanes. One of them was the Erlonok transport ekranoplan with a take-off weight of up to 140 tons, capable of carrying 20 tons of cargo at a speed of 400 km/h for a distance of up to 1500 km. This ekranoplan can take off and land on water with waves up to 2 meters high. It is amphibious, meaning that it can independently land on a relatively flat shore with natural cover, as well as on a special shallow pontoon cushion or on a prepared shore platform, which is necessary for the base of ekranoplanes.

The "Eaglet" is a free-flying monoplane that includes a streamlined fuselage with hydrodynamic and amphibious elements in the lower part and a well-developed tail section. The fuselage includes a crew cabin, a crew rest area, compartments for electronic and radio communication equipment, a cargo hold, and a separate compartment for the auxiliary power plant and onboard units that provide starting the main power plant engines and operating the screenplane's hydraulic and electrical systems.

The cargo hold occupies the main part of the fuselage and has a reinforced floor equipped with mooring devices with special sockets that allow for several options for securing cargo and wheeled vehicles, as well as seating blocks for transporting people.

A special cargo connector is provided in the nose of the ekranoplan for loading and unloading large-sized cargo and wheeled vehicles. This is a unique device that has no analogues in domestic or foreign practice.

The main power plant consists of one NK-12 cruise turboprop engine and two NK-8 launch turbofan engines designed by N.D. Kuznetsov and modified for marine operations.

The NK-12 turboprop engine provides economical cruising flight and is located on the vertical tail of the ekranoplan in the area of the stabilizer installation. This engine location is due to the need to remove it from sea water splashes during the start, landing and run of the ekranoplan, as well as to reduce its possible salting in flight from aerosols of the marine atmosphere, the saturation of which, as is known, depends on the altitude above the sea.

The starting engines operate only during the aircraft's takeoff and are equipped with swivel nozzles designed to change the direction of the engine jets during takeoff, under the wing to create an air cushion (blow-down mode), and during transition to cruising mode, to provide horizontal thrust to accelerate the ekranoplan to its cruising speed. The need for these operating modes of the starting engines, with the change in the direction of the gas jets, necessitated their placement in the nose of the fuselage at a specific angle relative to the longitudinal axis of the ekranoplan. The air intakes of the starting engines, as well as the engines themselves, are integrated into the overall shape of the ekranoplan's nose section to reduce aerodynamic drag during cruising.

The gas jets are blown under the wing during takeoff, which reduces the hydrodynamic loads, which is especially important when taking off in rough seas. The same purpose is achieved during landing and taxiing. In addition, the gas jets are used to provide amphibious properties to the ekranoplan.

The main control, hydraulic, power supply, and life support systems are designed to be similar to those used in aircraft. The systems and equipment are designed to be duplicated and redundant, ensuring the necessary safety during operation. When designing the Erlokk ground-effect aircraft, special attention was paid to the performance of the structures and equipment in marine environments.

It should be noted that in terms of survivability and traffic safety, ekranoplanes have significant advantages over aircraft, due to the fact that in emergency situations, including failures of the material part, an ekranoplane always has the opportunity to land on a water surface as a kind of airfield. This is what happened to the "Orlenok" and KM in difficult meteorological conditions.

Today, on the basis of the built samples, there are projects of ekranoplanes for various purposes and a much larger take-off weight compared to the "Eaglet". They can be used on the high seas and in certain ocean zones to solve various tasks for peaceful and military purposes.

In some modifications of marine ekranoplanes, it is possible to maneuver in terms of the height of movement up to purely aircraft modes, which is often necessary to ensure safety in the event of unexpected obstacles on the course of movement, as well as to reduce the path by flying over natural or artificial barriers that separate individual areas of marine water areas. Ekranoplanes of such modifications are called ekranolets.

The screen-planes and simplified modifications have been created for use on rivers, reservoirs, inland water bodies, as well as on relatively flat land areas, such as river floodplains or tundra, at any time of the year. They have a significantly lower speed range compared to marine vehicles (120-200 km/h instead of 320-500 km/h) and a lower altitude range (movement is mainly in the horizontal plane with minimal altitude variation), and are therefore referred to as dynamic air cushion vessels.

Unlike ekranoplanes and ekranoloty, no flight training is required to operate a dynamic air cushion vessel (DACV). Such vessels can be operated by crews of hydrofoil vessels (HFVs) who have received special training. DACVs do not have a rudder, and the main controls, like HFVs, are the engine controls for speed control and the rudder (or pedals) for course control.

R.E. Alekseyev developed the idea of a dynamic air cushion vessel in the late 1970s for the needs of the national economy. Under his leadership, the first design projects for passenger vessels of this type with a capacity of 8 to 250 people were completed, which are essentially a new generation of winged vessels. A characteristic feature of a dynamic air cushion vessel, as well as of an ekranoplan in general, is the presence of an air wing, but of a significantly smaller size. It is equipped with skegs on the sides, so that a dome-shaped bearing platform is formed, known as a "pressure wing". The dynamic air cushion in the pressure wing is formed by blowing, i.e. braking the air flow in it, created by a special air blower placed in front of the wing and forming part of the propulsion complex. Excessive pressure in the dynamic air cushion creates a lift force equal to or greater than the weight of the vessel, even when it is "on the ground" and moving at a minimum speed. As the speed increases, the lift force of the wing is assisted by the oncoming airflow and the increasing effect of the proximity of the support surface, i.e., the screen.

A few years ago, the concept of a dynamic air cushion vessel was tested on the first practical prototype of the nine-seater Volga-2 boat, which is a prototype for larger DAVPs. Based on the results of the Volga-2 boat, it is possible to create larger river gas turbine boats for 50, 90, and 120-150 passengers, such as the Raketa-2 and Meteor-2 boats. In principle, SDVPs can also be designed for marine use, such as the Vikhry-2 gas turbine vessel with 250 to 300 passenger seats. They can also be used for other purposes.

There is every reason to be proud of the country's scientific and technical achievements, as well as the construction and testing of individual models of various modifications and purposes, and the accumulation of sufficient operational experience for mass production.

Unfortunately, all promising work in this area has been suspended due to the country's difficult economic situation. There was hope for a Russian-American project to build a giant ekranoplan. It would have a total weight of 5,000 tons and a cargo capacity of 1,200 tons. The plan was to carry 3,000 passengers and travel at a speed of 800 km/h over a distance of 16,000 km. The business-minded Americans decided to see the "Caspian miracle" - the Erlenok-2 ekranoplan. They were taken to the base of the combat ekranoplanes and given a demonstration flight followed by a tour of the aircraft. The guests warmly thanked the military command and representatives of the Central Design Bureau for their hospitality and departed, taking with them technical information worth billions of rubles.

So far, there has been no mention of a "joint" project. There are rumors among experts that something is being done in the vicinity of San Francisco regarding the problems of the ekranoplan. It is possible that once we become rich, we will purchase the ekranoplan from the Americans. After all, the Nizhny Novgorod Central Design Bureau for Hydrofoil Boats named after R.E. Alekseyev is on its last legs. Only a third of the 1,500-strong team remains. In recent years, about a dozen firms and organizations have spun off from it. Such "firms" cannot create anything new, but they try to survive by selling used high-speed motor ships and, if possible, by stealing the creative legacy of the outstanding designer of winged ships, R.E. Alekseyev.

In connection with the celebration of the 300th anniversary of the Russian Navy, there were calls at the highest levels of government to revive it. However, the real challenge is not to revive, but to transform the fleet. In this regard, the first priority should be given to the high-speed vessels of the 21st century, such as the ekranoplanes designed by R.E. Alekseyev.