Ukraine Air Alliance — Flight UKL4050

A cargo-configured Antonov An-12BK crashed into a forest 1,359 meters short of the runway at Lviv International Airport during a low-visibility instrument approach. The aircraft was performing a scheduled refueling stop on a flight from Vigo, Spain, to Bursa, Turkey, when it descended significantly below the glide path without crew correction. Investigators determined that the crew was suffering from excessive physical fatigue, likely exacerbated by a long duty day and a late-notice change in the flight schedule. The impact destroyed the cockpit and caused the 10-ton cargo of automobile parts to shift forward, crushing the flight deck and killing five of the seven crew members. The remaining two crew members and one passenger (a cargo escort) survived with serious injuries.

Aircraft

Antonov An-12BK

Registration

UR-CAH

Phase

Cause

Souls on Board

Fatalities

Origin → Dest

Vigo-Peinador Airport (VGO), Spain → Bursa Yenişehir Airport (YEI), Turkey

Report

Investigation Summary

The flight originated in Vigo, Spain, carrying approximately 13,000 kg of automobile spare parts. During the approach to Lviv, the airport was experiencing dense fog with a vertical visibility of only 60 meters. Despite the challenging conditions, the aircraft was serviceable and the crew had captured the localizer for Runway 31. However, the aircraft began a premature and unconscious descent. At 3.3 km from the runway, the aircraft was already at 100 meters altitude. When the decision height alarm sounded at 60 meters, the crew failed to respond or initiate a go-around. The aircraft eventually struck trees at an altitude of only 5 to 7 meters above ground level. A contributing factor noted by investigators was a probable exceedance of the maximum takeoff weight at Vigo, which increased fuel consumption and limited the crew's options for diverting to an alternate airport like Boryspil.

Final Conclusions

The National Bureau of Air Accidents Investigation of Ukraine (NBAAI) concluded in its final report, published on 8 October 2021, that the most probable cause was the crew's failure to maintain the flight path in instrument conditions due to excessive physical fatigue. This fatigue led to an unconscious descent below the glide path and subsequent controlled flight into terrain (CFIT).

Photographic Evidence (1)

Ukraine Air Alliance, UR-CAH, Antonov An-12BK

Video Analysis

No video analysis linked for this case file yet.

Airframe & Maintenance

Airframe Hours

12,922

Cycles

6,616

Engines

Ivchenko AI-20M

Crew Experience

Captain

Total hours

6,750

On type

6,570

Fatal

First Officer

Total hours

14,670

On type

9,620

Fatal

Systems & Failure Modes

Instrument Landing System (ILS)

The aircraft was performing an ILS approach to Runway 31; investigators found the aircraft descended below the electronic glide path without crew intervention.

Radio Altimeter / Decision Height Warning

An audible alarm triggered when the aircraft reached the preset decision height of 60 meters, but the fatigued crew failed to react.

Interesting Facts

01The aircraft was built in 1968 and had accumulated 12,922 airframe hours.
02The cargo consisted of approximately 13,000 kg of automobile spare parts.
03There were 8 people on board: 7 crew members and 1 passenger (cargo escort).
04Five crew members were killed; two crew members and the passenger survived with serious injuries.
05The aircraft struck trees 1,359 meters from the runway threshold at an altitude of 5 to 7 meters.
06Ukraine Air Alliance had its air operator's certificate terminated the day after the accident.
07Investigators found a probable exceedance of the maximum takeoff weight (MTOW) at Vigo, which increased fuel consumption and limited diversion options.