Altimeter Error Blamed for Fatal Angara An-24 Crash

Post by : Amit

Photo : X / FlightGlobal

A Tragic Loss in Russia’s Far East

Angara Airlines Flight 2311, operating an Antonov An-24 aircraft, tragically crashed near Tynda in Russia’s Amur region, claiming the lives of all 48 people on board, including 42 passengers and six crew members. The flight had originated from Blagoveshchensk and was approaching Tynda Airport when it disappeared from radar during its final descent. The crash site, deep within a remote and forested area, posed significant challenges for rescue and recovery teams, delaying initial operations and complicating early investigation efforts.

This catastrophic accident has sent shockwaves through Russia’s aviation industry, local communities, and international observers. In addition to the immediate human toll, the crash has raised urgent questions about procedural compliance, operational safety, and the risks associated with aircraft navigation in remote regions. The preliminary investigation suggests a key role for an altimeter pressure error, a factor that underscores the critical importance of instrument accuracy and crew training in aviation safety.

Preliminary Findings: Altimeter Pressure-Setting Error

Russian investigators, led by the Interstate Aviation Committee (IAC), have pinpointed an altimeter pressure error as a central factor contributing to the crash. The aircraft was executing the non-precision BELIM 2A approach to runway 06 at Tynda Airport. During its descent, the flight crew incorrectly set the aircraft altimeter to the sea-level QNH figure of 751 mmHg (1002 mb), instead of the airfield-specific QFE pressure reference, which provides altitude relative to the airport elevation.

This missetting caused a substantial discrepancy between the aircraft’s indicated altitude and its actual height above terrain. According to Tynda Airport approach charts, the NDB navigation aid should have been crossed at 1,105 meters relative to the QFE pressure. With the QNH setting, the aircraft’s true altitude was over 600 meters lower than indicated, ultimately resulting in the aircraft striking trees approximately 15 kilometers from the runway at an elevation of 765 meters above sea level.

The incident highlights how even experienced flight crews can fall victim to a single procedural oversight, with catastrophic consequences. It also emphasizes the need for rigorous adherence to standard operating procedures and precise instrument interpretation to ensure aviation safety.

Environmental and Operational Factors

Although the weather conditions at the time were relatively moderate, they contributed to the crash’s complexity. Visibility was around 9 kilometers, with light rain and scattered clouds. Despite these favorable conditions, Tynda Airport is surrounded by hilly and forested terrain, with elevations rising to 850 meters within a five-kilometer radius of the airfield.

The combination of the misset altimeter and challenging topography created a hazardous environment for the approaching aircraft. The trees and uneven landscape made the consequences of the altimeter pressure error even more severe, leaving the crew with insufficient time to correct their descent path.

Remote and forested approaches like Tynda are particularly unforgiving. Pilots must rely heavily on instruments for terrain awareness, particularly during non-precision approaches without glide path guidance. This incident underscores how critical it is for aviation crews to maintain accurate instrument settings in regions with limited navigational aids.

Crew Experience and Aircraft Details

The flight crew aboard Flight 2311 were experienced professionals. The captain had accumulated nearly 6,000 hours on An-24 and An-26 aircraft, with a total of 11,200 flight hours across multiple types. The first officer had logged over 1,900 hours on the An-24 type alone.

Despite this extensive experience, the crew’s misinterpretation of the altimeter setting contributed to the tragic outcome. This underscores the broader lesson that even veteran pilots are vulnerable to procedural errors under complex operational conditions.

The aircraft itself, a 1976-model Antonov An-24 with registration RA-47315, had been maintained according to Russian aviation standards. While older than most modern regional aircraft, the An-24 has a long operational history and is known for reliability when maintained properly. Authorities are currently evaluating maintenance records, previous inspections, and operational history to determine if aircraft factors also played a role in the crash.

Regulatory Oversight and Immediate Safety Measures

Following the crash, Russian aviation authorities, led by Rosaviatsia, initiated a detailed review of altimeter-related procedures. The regulator has directed regional aviation bodies to enhance pilot and air traffic controller training on correct QNH and QFE pressure usage. Airports that recently transitioned to QNH procedures are receiving particular scrutiny.

Flight operations manuals are being revised to clarify altimeter use during approach and landing. Enhanced procedural guidance now emphasizes mandatory cross-checks and verification protocols, aiming to reduce the risk of errors similar to the altimeter pressure error that caused Flight 2311’s crash.

Authorities have also recommended additional simulator training focused on terrain awareness and approach planning, particularly in airports with challenging surroundings. These safety measures are intended to prevent recurrence and improve overall aviation safety standards throughout Russia’s regional aviation network.

Broader Implications for Aviation Safety

The Angara Airlines An-24 crash highlights a critical aspect of flight operations: accurate altimeter settings are essential for safe navigation, particularly in hilly or mountainous regions. Even minor procedural errors can escalate rapidly into fatal incidents when combined with challenging environmental factors.

International aviation safety experts note that the incident serves as a cautionary example for airlines worldwide, particularly those operating older aircraft in terrain-intensive environments. Accurate instrument interpretation, rigorous adherence to approach procedures, and comprehensive crew training remain the foundation of effective aviation safety.

The lessons learned from this tragedy are likely to inform operational procedures and training programs, not only for Angara Airlines but also for other carriers operating regional flights in Russia and similar terrains globally.

Operational Challenges for Angara Airlines

Angara Airlines has been under heightened regulatory scrutiny in recent months. The airline had its maintenance and training certificates revoked following inspections that uncovered procedural lapses. These regulatory challenges were compounded by the fatal crash, raising serious questions about the airline’s operational and safety practices.

The loss of internal training certification now forces Angara Airlines to rely on certified third-party organizations for pilot and maintenance training. These operational dependencies may slow recovery and create additional compliance challenges. Ensuring robust training, precise maintenance, and strict adherence to procedural standards is now critical for the airline’s ability to continue operations safely.

Human Factors and Crew Decision-Making

Investigators emphasize the role of human factors in the crash. Even highly experienced pilots are susceptible to error if procedural clarity, environmental stressors, and operational pressures are not managed effectively. The misinterpretation of altimeter readings by Flight 2311’s crew underscores the importance of scenario-based training and continuous proficiency checks.

Aviation psychologists recommend incorporating human factors analysis into standard training programs, emphasizing decision-making under stress, error recognition, and procedural compliance. Redundant safety checks, including cross-verification of altimeter settings between crew members, are now recognized as critical safeguards against incidents like the Angara Airlines An-24 crash.

Impact on Regional Aviation Operations

The Angara Airlines An-24 crash has broad implications for regional aviation in Russia. Flights across Siberia often operate in areas with limited navigation aids, harsh weather, and challenging terrain. Errors in instrument settings can therefore have magnified consequences.

Regulatory bodies are now likely to implement stricter oversight of regional carriers, with enhanced monitoring of procedural compliance, instrument training, and approach planning. Airlines may need to invest in modern navigation aids, better cockpit instrumentation, and additional crew support to meet evolving safety standards.

International Aviation Perspective

From an international perspective, the Angara Airlines crash reinforces the need for globally consistent aviation safety protocols. Older aircraft types, like the An-24, remain in service in many countries, often in regions with difficult terrain. The lessons from Flight 2311 highlight the importance of continuous crew training, procedural clarity, and regulatory oversight, regardless of aircraft age or operational region.

Airlines worldwide can draw insights from the incident, particularly regarding the criticality of altimeter settings, terrain awareness, and procedural redundancy. Such measures are essential for enhancing aviation safety and reducing the risk of similar accidents globally.

Future Directions for Angara Airlines

Looking forward, Angara Airlines faces a long path to restore operational credibility. The airline must demonstrate compliance with safety standards, maintain rigorous training programs, and ensure strict adherence to operational procedures. Collaborating with third-party certified training and maintenance organizations will be crucial in rebuilding confidence among regulators, passengers, and the aviation community.

The investigation into the crash will continue to shape the airline’s future policies, operational reforms, and approach procedures. Successful implementation of safety measures could restore both trust and certification, ensuring safer operations for Angara Airlines’ regional flights.

Lessons in Vigilance and Compliance

The Angara Airlines An-24 crash near Tynda on July 24, 2025, serves as a sobering reminder of the importance of vigilance, compliance, and precision in aviation. The altimeter pressure error that contributed to the tragedy underscores the critical role of accurate instrument settings, thorough training, and robust procedural adherence in maintaining aviation safety.

As the investigation continues, lessons drawn from this incident are expected to influence regulatory actions, pilot training programs, and operational standards across Russia and beyond. For airlines operating in challenging terrains with older aircraft types, the Angara Airlines crash highlights the imperative of rigorous oversight, meticulous planning, and unwavering commitment to safety—a commitment that is ultimately vital to protecting the lives of passengers and crew alike.

Aviation