Mar Caspio, March 19, 1968. A American spy satellite takes photos of a gigantic Soviet production plane. Or, to say better, of what at first glance may seem like a plane, but that looks more carefully it has some details that do not return: the tail is much bigger than usual, unlike the wings that are very short. In addition, it is in water. Americans rename it “The monster of the Caspian”and it is easy to understand why. But what exactly was it about?
Ekranoplano: What is it about? And what is the soil effect?
The mysterious object was a ekranoplanoan experimental vehicle that combined aeronautical and naval characteristics. Its operating principle was based onsoil effectan aerodynamic phenomenon that occurs when a plane flies at low altitude, generating an air cushion between the wings and the surface below. This effect reduces induced resistance and increases lift, improving aerodynamic efficiency. A practical example is observed in the last moments before the landing of an airplane, when it seems almost “floating” above the track before touching the ground. The idea of exploiting this principle led to the design of the ekranoplani, and in particular to the work of Rostislav AlèxeyevRussian engineer considered the father of these vehicles. However, few know that a significant contribution to development also came from the Italian engineer Roberto Oros of Bartinigraduated in Aeronautical Engineering from the Polytechnic of Milan and subsequently moved to the Soviet Union for political reasons. Thanks to these two pioneers, the Ekranoplani experienced a golden era, becoming an element of strong strategic interest for the USSR and a source of concern for the United States, in the middle of the technological competition of the Cold War.
In order to continuously exploit the soil effect, it is essential to have a surface without obstacles. The ideal environment for such a means is therefore water, which offers a uniform expanse on which to keep the flight at low altitude without interference. Starting from this principle, Soviet engineers therefore designed a hybrid vehicle between a plane and a ship, capable of exploiting the characteristics of both means of transport. The original model weighed 540 tonsit was almost long 100 meters and could reach the extraordinary speed of 550 km/h. The propulsive system consisted of two main engines located on the tail, while eight additional enginespositioned on the front, provided the initial thrust necessary to enter the soil effect mode. Once the optimal speed has been reached, these auxiliary engines were deactivated, reducing fuel consumption.
Military use, speed and characteristics
During the Cold War Getting funding for innovative projects was simpler if they had a military application. In this sense, the ekranoplane lent itself perfectly for the purpose. Its characteristics made it a highly strategic means: high load capacityideal for the rapid shift of troops and materials from one coast to another; efficiency in consumptionthanks to the reduced aerodynamic resistance guaranteed by the soil effect; low radar detectabilityas it flew a few meters from the surface, below the enemy radar horizon. One of the best known models, belonging to the classrepresented an evolution of the original prototype. This ekranoplano, long 74 meterswas equipped exclusively with the eight front engines and had a tail radar system. What made it particularly fearful was the armament: you are launch Installed on the fuselage, operational even during the movement, they transformed it into an extremely mobile and difficult to intercepable attack platform. Despite its enormous potential, however, the Ekranoplano never exceeded the boundaries of Caspian Sea. But what were the reasons that prevented its large scale spread?
The technical limits of the AKranoplano
Despite the numerous advantages analyzed, Ekranoplano also had two significant critical issues, which compromised its large -scale spread. The first big limit was linked to his interaction with sea conditions. At such high speeds, even waves of 1-1.5 meters They could generate considerable impacts on the hull, compromising the stability and structural integrity of the vehicle. This problem was relatively contained in Caspian Seaa sea closed with conditions similar to those of a large lake, but was particularly critical in the ocean, where the wave motion is much more unpredictable and intense. The second problem concerned the poor maneuverability of the Kranoplane. The vehicle had a limited ability to change direction quickly, which represented a significant risk in busy maritime areas, increasing the danger of collisions with other boats if not promptly identified. These two factors made the employment of Kranoplane extremely complex outside of controlled environmentslike lakes or coast stretches characterized by particularly calm sea. To determine the definitive arrest of the program was the collapse of the Soviet Union in 1991which involved the cessation of funding for the development of this technology. Today the Ekranoplano lu stands abandoned to Derbent, on the banks of the Caspian Sea, in the Daghetan.
A possible future for Ekranoplani?
Despite the abandonment of the Soviet project, the interest in this technology has not disappeared. Several companies all over the world are exploring new Ekranoplani applicationsespecially in favorable contexts such as i large lakes or maritime areas characterized by favorable conditions. An example is Airfish 8an ekranoplano designed for the transport of about 10 passengerscurrently in the test phase in the eastern waters of Singapore. This shows how, despite the limitations, the concept of Ekranoplano can still find concrete applications in specific operational scenarios, exploiting the advantages of the land effect to reduce consumption and improve the efficiency of maritime transport.
