1953 Kemerovo mid-air collision

During the flight, the crew of Li-2 aircraft A4031 maintained communication with the Novosibirsk Aerodrome Dispatch Service and airfield dispatch service but did not contact the Kemerovo ADS. Meanwhile, the crew of Li-2 aircraft L4534 maintained communication with the Krasnoyarsk ADS, RDS, and Kemerovo ADS, but their communication with the Novosibirsk RDS was unsatisfactory. As a result, the exact location of the aircraft within their respective zones was unknown to the RDS. Numerous eyewitnesses on the ground saw the two aircraft heading toward each other at the same altitude, with neither crew taking any evasive action to avoid the collision.

It is worth noting that the 6th Air Survey Unit was originally part of the Main Directorate of Geodesy and Cartography and was transferred to the West Siberian Territorial Directorate of Civil Aviation in March 1953, just two months before the accident. When the unit was integrated, the command of the West Siberian TU GWF failed to adequately address the organization and safety of flights. Only flight training for the crews was conducted, with little attention given to aerial photography operations, which were entrusted to unit commander Klykov, who had only started working in the unit in March 1953 and was also unfamiliar with the specifics of aerial photography operations. Meanwhile, while civil and military aviation flights are stratified, meaning they operate at specific altitudes based on standard pressure settings, the situation is different for aerial survey aviation. These aircraft operate at altitudes dependent on the specified scale of the survey, which in turn is determined by the aerodrome elevation with adjustments for the terrain's relief in the survey area. However, requests for aerial survey operations at Novosibirsk Airport were submitted without specifying the boundaries of the area, and the actual flight altitudes over the survey area did not match the submitted requests. For example, the assignment for aircraft A4031 specified conducting a survey at a scale of 1:17,000. Simple calculations show that the actual flight altitude relative to the departure aerodrome should have been ${\displaystyle 1700+(290-162)=1828}$, where 1,700 is the true altitude above the survey area's terrain, 290 is the average terrain elevation of the survey area above sea level, and 162 is the elevation of Novosibirsk Airport. Based on this, at standard pressure (760 mm Hg), the flight altitude should have been ${\displaystyle 1828+(760-745,5)*11=1987,5}$, where 745.5 is the pressure at Novosibirsk Airport. Since the pressure at Kemerovo Airport was higher, at 747.1 mm Hg, the flight altitude at standard pressure should have been ${\displaystyle 1987,5-17,5=1970}$, where 17.5 is the correction for the higher pressure at Kemerovo Airport. From these calculations, it is clear that before beginning the survey, aircraft A4031 should have climbed to an altitude of not 1,800 meters but 1,970 meters, meaning it should have gained an additional 170 meters. However, according to the barogram data, the aircraft actually climbed an additional 250 meters. It is noteworthy that neither the command of the West Siberian TU GWF, nor the Novosibirsk RDS and ADS, were aware of the correct method for determining survey altitude.

As for CCCP-Л4534, its commander, Stanishevsky, grossly violated the flight route on the Krasnoyarsk—Novosibirsk track by cutting a portion of the route near Kemerovo and not maintaining the prescribed flight level. Previously, in July 1952, Stanishevsky had been demoted to co-pilot for indiscipline and loss of orientation. He was reinstated in February 1953, despite retaining significant deficiencies in piloting, as well as displaying arrogance, stubbornness, and a lack of understanding.^[3]

At the Novosibirsk RDS, a radio direction finder was installed, but during the entire 35 minutes that aircraft L4534 was in its zone, it did not determine its location, leaving the Novosibirsk dispatcher unaware of the air traffic situation in the aerial photography area. The Kemerovo ADS dispatcher, when allowing aircraft L4334 to fly through its zone, was unaware of the aircraft's actual route and did not ascertain its precise location, although in clear weather, he could have observed the aircraft flying over the Kemerovo aerodrome. However, there was no overflight, as Commander Stanishevsky had cut the route to bypass the aerodrome. The Novosibirsk RDS did not warn the passing crews or the Kemerovo and Krasnoyarsk airports about flights taking place within its zone 50 kilometers north of Kemerovo Airport. Finally, the crews of both aircraft, despite the clear weather, did not monitor the air traffic situation and took no action to prevent the collision.

The causes of the aircraft collision were:

1. Gross violation of the established flight route and criminal negligence in piloting the aircraft by PIC Stanishevsky;
2. Lack of caution by PICs Stanishevsky and Lomov during the flights;
3. Inadequate preparation for aerial photography flights, poor flight organization, and disregard for basic flight safety requirements by the command of the West Siberian TU GWF and the 6th Air Survey Unit, as well as by the Novosibirsk RDS.

Those responsible: both PICs and Klykov, who took a formal approach to ensuring flight safety.

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