Malaysian Airlines MH370 contact lost

[felix505]

Visual horizon

Assuming the person on the "oil rig" had a viewing platform at an elevation of 30m above sea level, and he was observing a large light source at an elevation of 35,000 ft, then that light would be below the horizon at any distance greater than ~388.5km, that ignoring the effect of atmospheric refraction.
If he was at 40m above sea level then that light would be below the horizon at any distance greater than ~391.5km
He provides no time of the observation, that limits any projection of the aircraft along it's intended flight path.

So perhaps it would be informing to look toward IGARI at 6° 56' 12N 103° 35' 6E
If the observer was on a 40m elevated platform, viewing an aircraft on fire at 35,000ft, from his 40m elevated viewpoint at the cord position of at 08° 22' 30.23 N, 108° 42' 22.26 E as stated in his email, then IGARI is ~584km to the SW on a heading of ~254.7° from the oil rig, and the light would have been below his visible horizon (at ~391.5km).

Con Dao Airport (VCS) on Côn Sơn Island is ~230km to the west on a heading of 280⁰ from the oil rig position, it has a 1830m runway with a wet parking area at both ends.

The email indicates the light was seen high in the sky on a bearing of 265-275⁰ and it was "difficult" to determine distance, "50-70km" distance was approximated by the observer in his email.