Aviastar, a branch of PJSC IL, is one of the main participants in the co-operation programme for the construction of MC-21 aircraft. Until recently, Aviastar has been producing panel sets for fuselage compartments F1-F5, tail cone and airframe compartments, all 11 doors, as well as, together with AeroComposite, tailplane: keel and stabiliser complete with rudders and altitude rudders.
However, the main production task of Aviastar is the production of IL-76MD-90A heavy military transport aircraft in the interests of the Russian Ministry of Defence. In 2023, six such aircraft were manufactured in Ulyanovsk, and the plant plans to reach the annual production rate of 18 aircraft. For this purpose, the plant is modernising production and expanding the area for assembly shops.
In this regard, some of the work on the MS-21 programme is being transferred to other aircraft building enterprises. For example, the assembly of the airframe compartment will be performed by the Irkutsk aircraft plant, while the production of door parts and the tail cone has been transferred to the Sokol aircraft plant in Nizhny Novgorod.
The tail cone is one of the fuselage compartments in the tail section of the aircraft. The keel and horizontal plumage are installed on it. Sokol is now preparing a duplicate production of this unit for the MS-21 aircraft. The stamping, mechanical assembly, metallurgical, forging and pressing, foundry and assembly units will be involved in its production. Taking into account the planned volumes, the work on this topic allows to load the relevant workshops for a long time.
In order to organise the production of the MC-21 tail cone, Nizhny Novgorod aircraft builders have mastered the shot peening method of surface hardening. This specialised process makes it possible to increase tenfold the service life of parts that experience high loads during aircraft operation, which is one of the main parameters ensuring the safety of civil aviation.
In addition, Sokol produces parts of the MC-21 door opening mechanisms – these are mechanical components of locking systems, emergency opening systems and others. At the moment, the plant is finalising the mastering of this subject. The plant is also preparing for the production of a complex and critical unit: the stabiliser repositioning mechanism attachment (SRM) unit.
To reposition the stabiliser in the MC-21, a two-channel electromechanical system of Technodinamika Holding is used. The SRM operates from one channel, while the second one is in “hot standby”. This unit is one of the key elements of the aircraft control system, so special, highest requirements are imposed to reliability and quality of its connection with the fuselage.
Mastering the production of the MC-21’s tail cone and other components and assemblies allows Sokol Plant to significantly expand its production programme and, in addition to upgrading MiG-31 interceptors, to become a participant of cooperation in the construction of modern domestic civil aircraft.