Using the example of the "Superjet", Yakovlev explained how increasing the size of an aircraft affects its fuel efficiency, noting the physical limitations of small aircraft. This was stated by Alexander Dolotovsky, Deputy Managing Director of PJSC Yakovlev — Director of the Regional Aircraft branch.
According to him, small aircraft are subject to physical limitations that cannot be circumvented by design solutions.
Firstly, in terms of weight perfection, the smaller the aircraft, the worse it always is, since there are constants that cannot be removed from consideration.
Dolotovsky attributed operational damage and the human factor to such constants. From a certain size, the thickness of the skin is determined not by the calculated strength, but by the impact of stones, birds, ice and sand.
In addition, human dimensions cannot be scaled with the aircraft, which means that small aircraft have a disproportionately large proportion of the fuselage, doors, service areas and cockpit, which ultimately worsens the weight perfection of the structure, he added.
The second factor is related to aerodynamics and atmospheric properties.
Increasing the linear dimensions of an object moving in the air leads to a decrease in friction resistance. If we double the "Superjet", its aerodynamic perfection will automatically increase due to the decrease in the proportion of friction resistance. Accordingly, fuel efficiency will increase.
It should be noted that certification tests of the import-substituted Superjet SJ-100 with PD-8 engines are in full swing. During the next flight on December 11, the aircraft with tail number 94024 climbed to a height of 12,276 meters. 41 enterprises were involved in the work on the aircraft, Yakovlev noted.
