Russia Working On AN-124 Replacement: Dubbed ‘Slon’ or ‘Elephant’

For a few years now, Russia’s Central Aerohydrodynamic Institute has been working on an aircraft to fill the role of the Antonov An-124 heavy lifter. First unveiled as a model in 2019,  what can we expect from this aircraft named the ‘слон’ (slon) or ‘elephant’?

Russia Working On AN-124 Replacement: Dubbed ‘Slon’ or ‘Elephant’
The An-124 has been one of the main go-to aircraft for transporting extra large and heavy equipment. Photo: Getty Images

Replacing the An-124

It was back in November 2019 that we first saw a clear vision of Russia’s plan to replace the An-124. The Central Aerohydrodynamic Institute (TsAGI) showed off a model of their heavy-load transport aircraft named ‘Slon,’ Russian for ‘Elephant.’

Just like the An-124, Slon will be used to transport heavy and large-size cargo. Here’s what is planned for this new large aircraft:

  • Its range is targeted to be 7,000 km (4,350 miles)
  • The aircraft will have a speed of 850 km/h (528mph).
  • The maximum payload will be 50% more than the An-124, 180 tons compared to 120 tons.
  • Finally, the aircraft will require a runway of three kilometers.

“The work is carried out under a governmental contract with the Ministry of Industry and Trade of the Russian Federation within the framework of Magistral-technologies (Highway-technologies) R&D program.” -TsAGI

Like the An-124, the Slon will also be powered by four engines and have a ‘high wing’ design- with the wings mounted on the upper fuselage. Slon’s engines, however, are set to be Russian Aviadvigatel PD-35 advanced ducted-fan engines.

Russia Working On AN-124 Replacement: Dubbed ‘Slon’ or ‘Elephant’
An initial model of the Slon was released in 2019. Photo: TsAGI Press Service

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Aerodynamic testing during 2020

With the model made public in late 2019, TsAGI spent a good portion of 2020 conducting aerodynamic testing. In July 2020, the firm announced it was in the second stage of testing, where the scientists of the institute “analyzed the aerodynamic characteristics of the model at low flight speeds in the longitudinal and lateral channels in the wind tunnel T-102.”

“We were able to study the behavior of the aircraft model at different slip angles, determine the effectiveness of the elevators and rudders, and also evaluate the influence of the assembly elements on the lateral stability of the aircraft at low flight speeds. The results obtained have confirmed the stated design characteristics,” -Alexander Krutov, Junior Researcher, TsAGI

Russia Working On AN-124 Replacement: Dubbed ‘Slon’ or ‘Elephant’
Wind tunnel testing of the Slon model has been ongoing. Photo: TsAGI Press Service

TsAGI noted at the time that this stage of tests would be completed in 2020, with work in 2021 focused on improving the aerodynamic layout based on the test results. Design, take-off and landing mechanization of the aircraft wing and further wind tunnel research would also take place in 2021.

Filling an important niche

Alexander Krutov, a Junior Researcher at TsAGI, also notes that after the gradual decommissioning of the An-124 Ruslan, “a niche will be formed that can be filled with a new aircraft built on the basis of promising technologies.” Krutov believes that civilian cargo companies will become the main customer of the new aircraft. However, it is also expected that the military will be able to transport their cargo with this aircraft, complementing the operations of An-124s still in service.

When do you think this mammoth aircraft will finally become a reality? Let us know your thoughts in the comments.