Originally Posted by
AN2 Driver
That has been corrected.
The last transponder data were received from position N9.027 E39.153 about 21nm east of Addis Ababa at FL086. Terrain elevation at that point is 8130 feet MSL, FL086 reported by the Mode-S Altimeter (which always measures to standard pressure 1013 QNH) corrected for QNH indicates the aircraft was flying at 9027 feet MSL at that position.
Though it still isn't correct.
A pressure altitude of 8600' equates to approximately 9125' AMSL, so about 100' higher than the figure quoted by Avherald (they appear to have used the SL pressure lapse rate, which is greater than that at altitude).