@ThomasDoubting
According to this report they descended
to 1000m.
The daily also reported that a Singaporean air traffic surveillance and control unit had also picked up the signal to show MH370 "made a turn back before its altitude suddenly dropped from 10,000m to 1,000m".
Maritime agency says no information about signals from missing plane - The Malaysian Insider
But then again...
It was also reported that a Singaporean air traffic surveillance and control unit also picked up the signal that MH370 "made a turn back before it was reported to have climbed 1,000 metres from its original altitude at 10,000 metres”.
http://www.themalaysianinsider.com/m...alacca-straits
Which report is correct? Take your pick...