A crew of three and five passengers were on board a British Aerospace BAe-125-800B was on a domestic executive flight in Russia between Tyumen-Roschino International Airport and Neryungri/Chulman Airport on this day in aviation history in 2016.
Damage to the wing and engine inlet (Source; aviation-safety.net © MAK)
The flight was operated during the night and had been uneventful from take-off till the approach. The weather at the time was recorded as;
Visibility 10+ km
Wind 350º / 2 m/s (4 kts)
Clouds Broken at 190 meters (620 feet) Overcast with cumulonimbus at 510 meters (1670 feet)
Temperature / Dewpoint +4ºC
QFE 685 mm Hg (913 hPa /913 mb)
While the aircraft was descending towards the airport ATC informed the crew about the current altimeter settings;
QNH 1012 hPa
QFE 685 mm Hg
The crew radioed back: "I confirm 685, [...] is 1012 hPa do we understand it correctly?" To which the controller responded, "...QNH 1012, for information the height of the threshold is 08, 857 meters." (airport elevation at Neryungri/Chulman Airport is 2812 feet / 857 meters)
The crew misunderstood this interchange. They set the pressure on the altimeters at 1012 hPa in error. This should have been 685 mm Hg (913 hPa)
The damaged wing with the missing winglet (Source; aviation-safety.net © MAK)
In the dark of the night over featureless terrain, the aircraft descended below the safe sector altitude with the altimeter setting incorrect. Resulting in a two Enhanced Ground Proximity Warning System (EGPWS) aural warnings; "SINK RATE" three-second later followed by a "PULL UP" warning.
A short while later, 18 kilometers (10 nm) from the threshold of runway 08 the aircraft hit tree tops. The crew managed to keep the aircraft flying and regain some height and continued for a safe landing at runway 08 of Neryungri/Chulman Airport. A post-flight inspection revealed extensive damage to;
Wing leading edges (dents)
Winglets (Left winglet missing)
Right-hand engine inlet (dents)
Right-hand engine compressor
Right-hand horizontal stabiliser
The incident was reported to the Russian Interstate Aviation Committee Damaged engine (MAK)
(MAK) who launched an investigation (Source; aviation-safety.net © MAK) into the incident. Their report (in Russian) is available by clicking here. They identified the following contributing factors;
- Lack of flight preparation by the crew.
- Lack of knowledge by the crew to obtain the aerodrome pressure in hPa.
- Inattention by the crew when interpreting the QNH and QFE
- ATC Standard Operating Procedures were insufficient