Rather than using a straightforward multi-engine configuration with engines mounted on the wings, the Slesarev Svyatogor was designed to use engines housed within the fuselage that drove external propellers via a belt system.
Difficulties with the transmission system delayed the project and it was abandoned in 1921 after the death of Slesarev. The Svyatogor never flew. https://www.destinationsjourney.com/historical-military-photographs/slesarev-svyatogor/ #aeroplane #airplane #aviation #bomber #SlesarevSvyatogor #Svyatogor