Descent below the decision height and failure to execute a go-around in bad weather resulted in the crew of an IrAero Antonov An-24 flying the aircraft into trees at Blagoveshchensk.
Russia's Interstate Aviation Committee (MAK) concluded that the crew made an "erroneous decision" to attempt the approach in a turbulent thunderstorm and heavy rain, which greatly reduced visibility.
The landing runway had already been switched from 18 to 36, owing to the poor weather - introducing a tailwind component for the approaching aircraft.
On approach to runway 36 the aircraft (RA-46561) was still 350m (1,150ft) above the ground while just 3km (1.6nm) from the threshold - twice the height of the normal glidepath.
It subsequently descended rapidly, reaching a descent rate of 1,970ft/min (10m/s), prompting a warning from on-board systems.
Despite the runway switch, the visibility remained below minima. IrAero procedures required the captain to abort the landing if dangerous weather was present, but the crew continued to descend on the approach, MAK stated in its report on the 8 August 2011 incident.
Inadequate meteorological data and poor communication to the pilots about the actual weather conditions contributed to the crash.
The inquiry primarily attributes responsibility to the crew for failing to abort the approach despite the turbulence and rain, and visibility of just 400m - far below minima. Poor vertical visibility also meant there was no visual contact with ground references, and MAK says the crew was "obliged" to execute a go-around under such circumstances.
The aircraft drifted 210m to the right of the runway centreline at low altitude and hit a bank of trees at high speed. It skidded for 350m, suffering substantial damage, but all 37 occupants survived.
Russian authorities recently cited descent below minima in poor conditions as being a particular concern regarding aviation safety in the country.
Source: Flight International
