Incident Overview
Date: Sunday 31 January 1971
Aircraft Type: Antonov An-12B
Owner/operator: Aeroflot, Tyumen Civil Aviation Directorate
Registration Number: CCCP-12996
Location: 14 km N of Surgut Airport (SGC) –
ÿ Russia
Phase of Flight: Approach
Status: Destroyed, written off
Casualties: Fatalities: 7 / Occupants: 7
Component Affected: AileronsAilerons
Category: Accident
Aileron oscillations coincided with flap extension, leading to a left roll and undershot landing due to a hinge moment reversal caused by icing. The crew misinterpreted this as asymmetrical flap extension, resulting in a subsequent retraction of the flaps.Aileron oscillations coincided with flap extension, leading to a left roll and undershot landing due to a hinge moment reversal caused by icing. The crew misinterpreted this as asymmetrical flap extension, resulting in a subsequent retraction of the flaps.
Description
Aileron oscillations coincided with flap extension. The crew misunderstood this as asymmetrical flap extension and retracted the flaps again. The airspeed had dropped to 172 knots. The aileron suddenly deflected then , causing a left roll. The aircraft undershot the runway. The hinge moment reversal on the ailerons and subsequent loss of control was caused by icing.
Source of Information
https://www.airhistory.net/info/soviet.phphttps://www.airhistory.net/info/soviet.phpPrimary Cause
IcingIcingShare on:
