RuAviation

Modern civil aviation demands stringent flight safety standards. The MC-21 medium-range airliner showcases an innovative approach to addressing this challenge, combining an enhanced flight parameter monitoring system with an active sidestick controller. This combination provides a fundamentally new level of protection against hazardous situations.

According to Kirill Sypalo, Director General of TsAGI, a distinctive feature of the MC-21 is the monitoring of over ten critical flight parameters, significantly exceeding the capabilities of the previous generation of aircraft.

“If the Tu-204 was limited to four flight parameters (G-force, angle of attack, Mach number and speed), the MC-21 has limitations concerning over ten parameters, which has markedly improved flight safety. The introduction of sidestick controllers (both passive and active) has also had a significant impact on aircraft handling and cockpit ergonomics,” RIA Novosti quotes Kirill Sypalo as saying.

The parameters of the MC-21 integrated control system (ICS) mentioned by the TsAGI Director General, include, inter alia:

• Dynamic load factors – the system prevents the aircraft from exceeding safe limits of +2.5g/-1.0g,
• Critical angle of attack – prevents stalling,
• Flutter prevention – protection against exceeding Vmo/Mmo,
• Lateral stability – automatic correction in strong crosswinds,
• Bank and pitch – prevention of abrupt manoeuvring.

The MC-21’s active sidestick controller provides tactile feedback to the pilot. Unlike the passive systems used in the Airbus A320 or the Chinese C919, this Russian design not only transmits commands, but physically resists unsafe pilot inputs. As critical regimes are approached, the stick changes force or vibrates, alerting the crew to a potential hazard.

Additional parameters of the ICS, according to TsAGI data, include yaw control, prevention of excessive aileron or elevator deflections, automatic lateral trim in the event of engine failure (Automatic Thrust Asymmetry Compensation), as well as engine operating mode control to coordinate with aerodynamic limitations. This multi-faceted protection significantly reduces the probability of crew error.

Comparison with foreign designs highlights the advantages of the Russian approach. The Boeing 737 MAX, like the Tu-204, was initially limited to monitoring four basic parameters. This simplification of ICS algorithms was a contributing factor to the problems with the MCAS system, which led to two crashes of the advanced American airliner. The Airbus A320’s ICS, in turn, uses a passive sidestick control system and monitors 7-8 flight parameters. The MC-21 offers a more sophisticated solution: a combination of an extended set of limitations with active feedback via the sidestick creates a robust safety barrier.

The prospects for further development of the system look interesting and promising. Adaptive algorithms could be introduced in the future, which will tailor the handling characteristics to the individual piloting style. Integration with air traffic management systems is also being considered for automatic route adjustments in response to changing external conditions.

Furthermore, Kirill Sypalo stated that research is currently being conducted in a direction that will improve the aircraft’s handling characteristics in a number of flight regimes, including landing in crosswinds.

The MC-21 sets a new flight safety standard in civil aviation, demonstrating the benefits of a comprehensive approach. The combination of multi-faceted flight parameter monitoring with an intuitive control system via the active sidestick creates effective protection against the occurrence of hazardous situations, which could potentially serve as a benchmark for new generations of passenger airliners.

** Vmo – Maximum Operating Speed, Mmo – Maximum Operating Mach Number.