Aeroflot Flight 8641
Yakovlev Yak-42 · Jackscrew failure due to metal fatigue; design flaw
From Pulkovo Airport (LED) to Igor Sikorsky Kyiv International Airport (Zhuliany) (IEV)
Event
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- Event fatalities
- 132 · all aircraft and ground
- Ground fatalities
- Unknown
- Occupants
- 132
- Survivors
- 0
- InjuriesFatal: death within 30 days. Serious: over 48 hours in hospital within a week, most broken bones, severe bleeding, nerve or organ damage, or serious burns. Minor: anything less. Glossary
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Airline
Yakovlev Yak-42
- Flight
- SU8641
- Aircraft type
- Yakovlev YAK-42
- Category
- Airplane · from aircraft type
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- СССР-42529
- Operator
- Aeroflot
- Onboard fatalities
- 132
- Route
- From Pulkovo Airport (LED)To Igor Sikorsky Kyiv International Airport (Zhuliany) (IEV)
Cause areas
- Aircraft › Aircraft systems
- Organizational issues › Development
- Aircraft › Aircraft handling/service
From the investigation findings the Wikipedia article reports, sorted into the NTSB's cause areas with AI assistance.
Approximate · Coordinates from the Wikipedia article; not checked against an investigation report.
From the Wikipedia article
Aeroflot Flight 8641 was a Yakovlev Yak-42 airliner on a domestic scheduled passenger flight from Leningrad (now Saint Petersburg) to Kiev (now Kyiv). On 28 June 1982, the flight crashed south of Mazyr, Byelorussian SSR, killing all 132 people on board. The accident was both the first and deadliest crash of a Yakovlev Yak-42, and remains the deadliest aviation accident in Belarus.
The cause was a failure of the jackscrew controlling the horizontal stabilizer due to a design flaw.
Sequence of events
The aircraft took off from Pulkovo Airport at 9:01 MSK - Moscow Time, having been delayed one minute because of a late passenger. At 10:45 MSK it entered the zone of Kiev/Boryspil air traffic control Center. The crew started the landing checklist at 10:48:01. At 10:48:58 the crew informed the air traffic controller they reached the planned top of descent point, the controller clearing them for descent to 7800 m. The crew confirmed the flight path; no further communications were heard from Flight 8641.
At 10:51:20 MSK the autopilot gradually brought about a horizontal stabilizer angle of up 0.3° to begin descent. At 10:51:30 the stabilizer angle sharply increased, exceeding the 2° limit within half a second. The sudden change resulted in a negative g-force of -1.5 g, but the autopilot adjusted the controls to lower it to -0.6 g. The stabilizer did not respond to commands and the plane continued diving, the autopilot switched off after 3 seconds. The pilots pulled back on the yoke trying to level out the airplane, but it continued in a steep dive; soon it rolled 35° left and the dive achieved 50° nose down. As it rolled counterclockwise with over -2 g of overload, the aircraft disintegrated at 10:51:50 at an altitude of 5700 m and an indicated speed of 810 km/h.
The wreckage was found on the outskirts of Verbavychi village, 10 km southeast of the district center Naroulia (itself being further 18 km south/west of the larger Mozyr which is often listed.) Fragments of the plane were scattered across an area of 6.5 by 3.5 km. All 132 people on board perished.
Investigation and cause
Cause
The cause was determined to be a failure of the jackscrew mechanism in the aircraft's tail due to metal fatigue, which resulted from flaws in the Yak-42's design. The investigation concluded that among the causes of the crash were poor maintenance, as well as the stabilizer not meeting aviation standards. Three engineers who signed the jackscrew drawings were convicted.
As for the official cause of the crash: "the spontaneous movement of the stabilizer was due to disconnection in flight of the jackscrew assembly due to the almost complete deterioration of the 42M5180-42 thread-nuts due to structural imperfections in the mechanism." Due to the accident, all Yak-42s were withdrawn from service until the design defect was rectified in October 1984.
Text from the Wikipedia article “Aeroflot Flight 8641” (revision 1339317716, retrieved 2026-09-18) by its authors, under CC BY-SA 4.0. Extracted as plain text: references, tables, images and some sections are left out. Read the article
Sources
Wikipedia article: Aeroflot Flight 8641
- Article
- Aeroflot Flight 8641
- Revision
- 1339317716 · 2026-02-19 · retrieved 2026-09-18
- Wikidata
- Q11737212
- Licence
- Text CC BY-SA 4.0, by the article's authors; Wikidata CC0; town positions GeoNames (CC BY 4.0)
Where each value comes from
- Record
- Wikipedia article "Aeroflot Flight 8641" (page 40019369, revision 1339317716)
- Date
- Wikipedia infobox: date
- Place and country
- Wikipedia infobox: site
- Map position
- Wikipedia article coordinates
- Aircraft, operator and route
- Wikipedia infobox: aircraft type, registration, operator, origin and destination; route airports from the linked airport articles' Wikidata codes (OurAirports)
- Operation
- airline flight number in the infobox
- Fatalities
- Wikipedia infobox: aircraft fatalities
- Ground fatalities
- not stated in the Wikipedia infobox
- Summary
- Wikipedia infobox: summary
Source notes (1)
- Wikipedia · Facts from the Wikipedia article's infobox and coordinates, not checked against an investigation report. Independent review pending.