Accident An-24 near Mukachevo

An-24B with tail number CCCP-46357 (serial number 07305807, serial number 058-07) was launched by the Kiev Aviation Plant on January 23, 1970 . The airliner was handed over to the Ministry of Civil Aviation , which sent it to the Kiev Joint Aviation Squad (86th Flight Detachment) of the Ukrainian Civil Aviation Authority by February 2 . The total operating time of the board 46357 was 9280 flight hours and 8083 take-off-landing cycles ^[3] .

• The aircraft commander - Komissarov Pavel Dmitrievich
• Co - pilot - Gennady Vasilyevich Evnitsky
• Navigator - Grisyuk Alexander Petrovich
• Bortmekhanik - Borovkov Victor Pavlovich
• Stewardess - Slepukhina Zinaida N.
• Accompanying policeman - Oleg Lazarets

The aircraft was supposed to perform an internal passenger flight N-75 along the route Kiev - Ivano-Frankivsk - Uzhgorod . However, that day , the Uzhgorod airport could not receive airplanes, since the surface of its airfield was in unsatisfactory technical condition, so the planes landed in the neighboring military airfield Mukachevo . But Mukachevo was also closed due to bad weather conditions, which is why flight N-75 had to delay with a departure at Ivano-Frankivsk airport ^[4] .

After the weather improved, along the route, according to the existing forecast, a large number of cumulus clouds were expected with a lower boundary of 100-150 meters and an upper boundary of 500-1000 meters, visibility of 1000-1500 meters, haze, icing in the clouds. At 14:51, the N-75 flight took off from Ivanovo-Frankivsk and after climbing at 14:57 it took the echelon of 3,000 meters, but at 15:04 the dispatcher in Lviv ordered to drop to the echelon of 2,400 meters due to the air situation. At 15:09, the plane reported the passage of the intermediate point of the Vysokoye route at an altitude of 2400 meters, after which the crew switched to communication with the manager of the Mukachevo airfield and continued flying at a speed of about 400 km / h ^[4] .

At around 15:14, 4 minutes before the passage of the Sredniy point, the crew began to descend to a height of 2100 meters with a vertical speed of 7.5 m / s, and then reduced the speed to 300 km / h. Further, the crew continued to decline to a height of 400 meters, probably having previously released the chassis. In the process of decline, the An-24 went into cloud cover, from which it emerged after 6 minutes. At that time, the sky over Mukachevo was covered by cumulonimbus clouds 120 meters high, air temperature −1 ° С, calm and a haze hung in the air, and visibility was 1100 meters ^[4] .

The dispatcher indicated that the landing would be carried out at a magnetic course of 22 °, after which, according to his instructions, the crew lay down on the reverse course to the landing, and began to make a third turn 11 kilometers from the runway . Then, heading for the fourth turn at a speed of 310 km / h, the pilots released the flaps into the pre-landing position, after which the speed dropped by 45 km / h in 50 seconds, therefore, at a speed of 260 km / h, the engine mode was increased. When, at about 3:24 p.m., the aircraft completed its fourth turn and entered the landing course, the engine operating mode was reduced, and the flaps were fully released. After 16 seconds, the speed dropped to 240 km / h and the crew again increased engine mode. The speed first fell to 220 km / h, and then increased to 230 km / h, so the engine mode was again slightly reduced ^[4] .

The plane was 200 meters above the ground, when the pilots, in an attempt to level it, first turned the elevator down. The plane steeply bent its nose down, so the elevator was tilted up to raise its nose, but the airliner rushed to the ground entering the left bank to 30 °. The pilots tried to level the car, but at 15:25 the inverted An-24, falling at an angle of 70 °, 100 meters behind the DPRM cut off wires on wooden poles, then crashed into a dirt road on the field, completely collapsed and burned down. All 24 people on board died ^[4] .

After studying the flight data and examining the wreckage of the aircraft, the technical commission concluded that the de-icing system did not turn on.

The cause of the flight accident is the loss of longitudinal controllability on the pre-landing straight line due to a possible insufficient margin at the angles of attack of the horizontal tail in the landing configuration with flaps 38 ° released when flying under conditions of weak icing.
Related reasons:

1. Lack of warning information to the crew about the stabilizer reaching angles close to critical.
2. Failure to turn on or off the PIC of the wing and stabilizer in the presence of weak icing (2-3 mm).
3. Lack of reliable on-board information about the presence of aircraft icing.

- ^[4]

Also in the final report, representatives of the Ministry of Aviation Industry recorded the following wording:

• Description of the incident on the Aviation Safety Network
• Crash of an Antonov AN-24 in Mukachevo: 24 killed (inaccessible link) . B3A Aircraft Accidents Archives. Date of treatment March 31, 2015. Archived April 2, 2015.