How much time does it take to put together thousands of individual parts, assemblies, and systems into a complete MC-21?
The answer from the director of the Irkutsk Aviation Plant is currently around 11–12 months. But there’s a key condition that makes this figure much more interesting: the airplanes reaching the flight-test stage are not yet fitted with their passenger interiors.
This means that the 11-12 month manufacturing cycle should not be considered as the period required to manufacture a fully finished passenger aircraft, ready for an airline to put into commercial operation. The present production process involves a structural assembly, systems installation, and preparation for flight testing, with the cabin interior completed at a later stage.
That distinction provides a much clearer view of how the MC-21 production program is positioned today.
Eighteen aircraft are in manufacturing system
Andrey Soinov, general director of the Irkutsk Aviation Plant, told TASS that the plant is presently producing 18 MC-21 planes. They are not processed in the same configuration at the same time but are at different stages of completion.
Ten aircraft have now been assembled into complete airframes, with systems installation already underway. Other airplanes are still built from individual aggregates and components before going to the next phases of the production line.
And this is significant because airplane manufacture is not a process where you put an aircraft in an empty building and 12 months later it comes out. There are multiple planes at different points in the production cycle at once.
While one MC-21 is undergoing systems installation, another may still be at the structural assembly stage, and a third is being prepped for transfer to the flight-test organization.
The aim is to create a continuous rhythm, not just to minimize the calendar time of one aircraft.
What happens during those 11–12 months?
Soinov described the process as beginning much earlier than final assembly.
The production chain begins with metallurgy and the delivery of materials. Those materials are processed into individual parts, assemblies, and aircraft skins. The airplane then travels along the production line, and more components are added until the airframe becomes an aircraft.
Irkutsk is only a small part of the production network. A large part of the aircraft’s wing structure is produced in Ulyanovsk, and Kazan and Dubna are also involved. The result is a nationwide system of industrial cooperation feeding the production line of Irkutsk.
So boosting MC-21 output is not simply an issue of putting additional people in the final assembly hall. All upstream production stages should be capable of supplying parts and assemblies at the needed pace.
The surprising part: the first aircraft flies without interiors
One of the more crucial nuggets in the interview is what happens to an MC-21 as it rolls out of the factory for flight testing.
Soinov was asked what form the aircraft is submitted for flight testing. His answer was straightforward: the first airplanes are flown without the interior installed. In the future, the cabin will be mounted at the last stage.
That’s why an aircraft in the flight test stage can appear to be far more complete from the outside than it actually is from the perspective of an airline passenger aircraft.
The passenger cabin is not being abandoned or designed later. Soinov said that the requirements already exist and that the interiors themselves have already been manufactured. These will be mounted on the aircraft after flight testing.
The interior is made in Kazan by the business “Aviation Interiors.”
So the figure for 11-12 months has to be seen in that sequence of production. It depicts the current aircraft assembly cycle toward the flight-test stage, not necessarily the elapsed time until all the passenger-facing elements are fitted and the aircraft is equipped for airline operations.
Why leave the interior out initially?
There is a practical industrial logic in separating the flight-test aircraft from the final passenger configuration.
Those tasks would include adding equipment, furnishings, and cabin components to an aircraft that is still in the testing phase. The aircraft has to be flight tested and go through various acceptance procedures, including installing the full airline interior.
Thus, for the first serial aircraft, Irkutsk uses a technique in which the aircraft can be transferred to flight tests before the final assembly of the cabin.
But in the longer run, Soinov said the objective was to fit out interiors at the Irkutsk factory in the last stage. There, the factory will also paint planes for consumers.
This is another step in the transition from a production program that was approaching serial manufacturing to a mature production line that will deliver aircraft in a repeatable airline configuration.
Why demand matters
The current 11–12-month cycle is not being presented by Irkutsk as a fixed technological limit.
Soinov explicitly said that the assembly time depends on demand. As demand develops, the plant wants to speed up the aircraft movement down the production line and raise its production rate.
The goal is ambitious: Irkutsk intends to attain 36 MC-21 aircraft a year.
To do that, the firm would have to maintain a far more constant flow of aircraft through its production sites. The final assembly shop has already undergone major transformation and, according to Soinov, is equipped for increased production volumes. The next emphasis is on the upstream manufacturing stages, particularly blanking, stamping, and mechanical assembly.
The real challenge is production rhythm
The importance of the 11–12-month figure is therefore not simply the number.
The MC-21 is a long-cycle product, and a lot of time passes between the creation of basic materials and the appearance of the finished aircraft, the plant director said. Long-term contracts are regarded as crucial since they enable the manufacturer to maintain a steady, predictable flow of output, rather than having to start and stop the line regularly.
The current batch of 18 aircraft for Aeroflot is a case in point. The aircraft are being manufactured in tandem at varying levels of readiness, not one by one. The first aircraft has already undergone flight testing, while others are still being assembled. The firm intends to deliver four aircraft to the flight-test site by the end of 2026.
But even once an aircraft begins flight testing, the production narrative may not be over. Cabin interiors for the first series of MC-21s will still have to be installed following the flight-test phase.
From building airplanes to flying airliners
This is what eventually makes the current MC-21 production program important.
Now Irkutsk is showing more than its ability to assemble an aircraft. It is trying to build a repeatable production system that can turn out airplanes in greater quantities.
Thus the present 11–12 months must be seen as a picture of a production system that is still being speeded up and refined.
The next phase is to speed up the pace of the line, enhance the upstream manufacturing chain, and finally incorporate the final installation of the interior into the production process.
If the plant hits its aim of 36 aircraft a year, the big achievement won’t be just building one MC-21 faster. It will be a constant industrial flow where structures, systems, testing, interiors, and the final preparation of the aircraft will all be integrated.
The question for the MC-21 is no longer just “How long does it take to build one aircraft?”
It’s becoming a much bigger question: How quickly can Russia turn its 11-12 month production cycle into a steady supply of full passenger aircraft?