#AeroAESA: Ekranoplan and Ekranolyot: The Bartini BerievVVA-14
- Umberto Minasola
- 1 giorno fa
- Tempo di lettura: 6 min
If you’ve ever had a quadcopter drone, you’ve probably experienced its strange behavior during the landing phase: you set a constant, low vertical speed to allow it to descend, but at a certain point, it starts bouncing up and down and stops in midair just a few centimeters from the ground. This forces you to further decrease the vertical speed to finally get it down.
How can this occurrence be explained? The answer lies in the phenomenon of “ground effect,” which highlights how the induced drag of a wing near the ground undergoes a slight reduction. This allows aerodynamic efficiency to increase without changing lift. Consequently, your drone finds it easier to stay in the air.
WIG vehicles, fundamentals
The ground effect was already well known more than 100 years ago when pilots noticed difficulties in landing their airplanes just before touching down, without applying an additional reduction of power. In the following decades, a new type of aircraft emerged based on this concept: the WIG (wing-in-ground effect) vehicle, also known as the ekranoplan. Thanks to the ground effect and increased aerodynamic efficiency, these machines were designed to be more fuel-efficient than regular jetpowered aircraft.
The Soviet Union was the world leader in the construction of these astonishing machines, indeed they recognized their huge potential in various applications—mostly military, but also for replacing passenger aircraft and ships on domestic travel routes. Their need to travel long distances at a speed comparable to a turbojet airplane required large, flat environments, available only over the water surfaces of seas. That’s why ekranoplans were essential hybrid machines capable of staying afloat and taking off from water. For this reason, the Caspian Sea became the main testing location for Soviet ekranoplans.
The Central Hydrofoil Design Bureau was significantly active in designing different types of ekranoplans. Among the most famous machines are the Orlyonok (Project 904—a 140-ton troop transport/assault ekranoplan), the Lun-class (Project 903—a 400-ton ekranoplan carrier armed with anti-ship missiles), and the legendary KM Caspian Sea Monster, the largest ekranoplan ever made, with a MTOW (Maximum Takeoff Weight) of 544 tons—100 tons more than the MTOW of a Boeing 747-8. All these ekranoplans were developed for testing and military purposes, with their key advantage being their ability to avoid radar detection thanks to their very low flight altitude.
Beyond these three classic machines, a large number of WIG vehicles were built in various types and dimensions—some even stranger than one might imagine.
A different pattern: the Bartini’s view
Robert Ludvigovich Bartini was an Italian aeronautical engineer who worked in the Soviet Union and contributed to the design of various aircraft. He was well known for his creativity in developing highly unconventional transport and combat flying machines, with a particular focus on ground-effect vehicles. The ekranoplan was itself an experimental machine under development for multi-role applications, but Bartini took this concept even further by coining the term “ekranolyot”—a vehicle capable of flying both within and outside the ground-effect phenomenon, depending on the situation and mission requirements. This would be physically possible by adjusting engine power.
The debut of Polaris submarine-launched missiles in the United States during the Cold War urged the Soviet Union to focus its efforts on building an innovative vehicle with multiple features, armed with anti-submarine warfare capabilities in response to the threat. A possible answer emerged in 1965 when Bartini proposed the construction of an amphibious VTOL aircraft named the VVA-14, which stands for Vertical Take-Off Amphibious Aircraft (in Russian). It was designed to be equipped with 14 engines and capable of taking off from land, water, or even snow-covered surfaces, with or without a runway. The aircraft was configured to fly close to the ground or water surface using ground effect, as well as at altitude like a conventional airplane, and could stay afloat indefinitely with its engines shut off.
The performance requirements aimed for a cruise speed between 650 and 750 km/h, a high service ceiling (10–12 km), and a range of 4,000 to 4,500 km, assuming an armament load of two tons. For its time, such a machine was remarkably pioneering. The design of the VVA-14 primarily prioritized range capabilities and aerodynamic efficiency rather than speed and altitude performance. The ground-effect flying configuration, in particular, was expected to provide significant fuel savings. The design project incorporated two D-30M turbofan cruise engines with thrust vectoring and twelve Kolesov RD36-35PR lift engines for vertical take-off.
The aircraft was intended for military, patrol, and search-and-rescue missions, but its aerodynamic performance was also an important area of study for the development of “Project T”—a series of passenger ekranolyots that unfortunately remained only at the preliminary design stage.
The airframe layout featured two large pontoons linked to a very thick, low-aspect-ratio wing, which would have generated a “cushion of air” by leveraging ground effect. The main fuselage was designed to be fixed at the center beneath the wing, between the two pontoons. Two additional low-aspect-ratio wings were installed externally to the pontoons, outside the ground-effect region.
This unusual configuration—somewhat resembling a flying catamaran—was devised to house the 12 lift engines in the main fuselage while integrating inflatable pontoons into both pontoons, providing buoyancy for water operations. The aircraft measured 25.95 meters in length, 6.79 meters in height (including pontoons), and had a wingspan of 30 meters.
The planned crew consisted of a pilot, a navigator, and a weapon-system operator, with all three seats designed to include ejection capability. The aircraft was also expected to feature an auxiliary power unit (APU), early-stage fly-by-wire flight controls, and advanced military navigation and weapon-delivery systems.
From paper to reality
The construction of the ekranolyot was carried out by the TANTK Beriev factory. Three prototypes were ordered, with the first intended as a testbed for aerodynamic and stability studies.
The first VVA-14 prototype, designated M1 and registered as CCCP-19172, was built without the twelve Kolesov lift engines, as they were still under development at the time. As a result, the main undercarriage was modified. The ekranolyot took to the skies for the first time in 1972, performing its maiden flight by taking off from a concrete runway like a conventional airplane. It demonstrated good stability and controllability, with the only issue being a severe vibration in a hydraulic pipe that caused a complete loss of fluid in one of the two hydraulic systems.
In 1974, the aircraft was equipped with inflatable rubber/fabric pontoons in preparation for future water tests. However, Bartini passed away in the same year, and the program began facing funding difficulties due to the TANTK’s increasing focus on three other aircraft projects: the A-40 (a jet-powered hydroplane), the A-50 (a modified version of the Il-76 with AWACS capabilities), and the Il-78 (the successor to the Il76).
Despite these obstacles, the project continued, and the M1 completed more than 100 test flights by mid-1975. In 1976, engineers realized that two of Bartini’s projections had become reality, leading to several significant modifications to the VVA-14 experimental airframe: the inflatable pontoons proved unreliable at high speeds and were replaced with rigid ones. The Lotaved bureau never delivered the lift engines, so the decision was made to eliminate them entirely. In their place, two additional D-30V booster engines were installed on either side of the cockpit, requiring the fuselage to be stretched. As a result, the ekranolyot was renamed 14M1P, and it was no longer designed for vertical takeoff. Additionally, the landing gear was reconfigured for a third time.
Engineers believed that the strategic placement of the boosters would create a powerful airflow beneath the low-aspect-ratio wing and between the main fuselage and the pontoons, reinforcing the ground-effect phenomenon and helping overcome water drag during takeoff. However, subsequent tests were disappointing, as the aircraft failed to lift off both from a concrete runway and from water. Further modifications were planned, but the Soviet Navy gradually lost interest in the project. Ultimately, the ekranolyot program was permanently discontinued, with the aircraft accumulating over 100 flight hours before its retirement.
The only prototype to have flown is now the sole example displayed worldwide at the Monino museum in Moscow—in very bad conditions and without its large external wings.
Conclusions: the past and the present
We cannot overlook that the Soviet Union was an empire of aerospace experimental vehicles. A vast number of unconventional flying machines—from ekranoplans to Roscosmos spacecraft—were built, though most ended their careers only as prototypes. Additionally, many civil aviation airliners met the same fate, stalled in their early testing stages without ever entering the commercial market.
Today, ekranolyot machines no longer exist, but in the decades following the collapse of the USSR, ekranoplans saw renewed interest in certain applications around the world. Currently, small WIG vehicles are available on the market, such as the German AirFish 8 and the Singaporean SeaWig SW-12. This niche industry keeps the myth of ekranoplans alive, though on a much smaller scale compared to the majestic Soviet vehicles we often envision.
A CURA DI
Umberto Minasola
Fonti
Russia’s Ekranoplans – Red Star Volume 8 – Sergey Komissarov https://www.militaryfactory.com/aircraft/detail.php?aircraft_id=1499 https://www.testpilot.ru/russia/bartini/vva/vva_e.htm
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