Flight MH370 Timeline/SoM-ANDS
Straits of Malacca to Andaman Sea
From 1:52 MYT to 2:22:12 MYT Template:Day 001
(17:52 UTC to 18:22:12 UTC Friday, 7 March 2014)
1. Last Primary Radar Observation at 1822:12 UTC (0222:12 MYT)
The last Military primary radar observation of MH370 is described in the Safety Investigation Report MH370/01/2018 as follows:-
At 1803:09 UTC [0203:09 MYT] the “blip” disappeared, only to reappear at 1815:25 UTC [0215:25 MYT] until 1822:12 UTC [0222:12 MYT], about 195 nm from Butterworth, on a heading of 285°, speed of 516 kt and at an altitude of 29,500 ft.
The radar track of MH370 is shown in Figure 2 opposite.
- The civilian Air Traffic Control radar track (secondary radar) is shown as the pale line from Kuala Lumpur to the last secondary radar observation at 1722 UTC (0122 MYT).
- The Military primary radar track is shown as a yellow line from the turnback near waypoint IGARI, across Malaysia and north-west along the Malacca Strait.
The exact latitude and longitude of MH370 at 0222:12 MYT is not provided, but from the graphic it can be seen that MH370 is located north-east of the tip of Sumatra and heading north-west towards the Andaman Sea.
2. SATCOM Log-on Request at 1825:27 UTC (0225:27 MYT)
At 0225:27 MYT the satellite data unit (SDU) on MH370 seems to have recovered from a power interruption and initiated a log-on sequence with the Inmarsat satellite communication system. The satellite data link was lost some time between 1707:48 and 1803:41 UTC, possibly due to a loss of electrical power. The reasons for these events is discussed in the Safety Investigation Report MH370/01/2018 and the extracts linked from each event in the Timeline.
Investigators have called this log-on event the first ‘handshake’ - because it was a successful communication between the aircraft and the ground station via the satellite.
The other benefit of this communication is the metadata associated with this transmission - the Burst Timing Offset (BTO) provides an indication of the distance of the aircraft from the satellite at that time. This is shown graphically (with other 'handshakes') as a series of concentric circles, or rings, in Figure 18 below. Since only part of the ring is technically feasible, the valid section is called an 'arc'.
In the diagram opposite, the position of MH370 is shown on this first, 1825 UTC arc.
It seems unlikely that the heading has changed significantly in the short period since the last primary radar observation.
Malaysian Military Radar
On this page the military radar observations provide a context and background for other events related to flight MH370 during the 'Air Turnback' - from the loss of contact to the last primary radar observation as MH370 was heading towards the Andaman Sea, west of Malaysia.
A 'blip' believed to be MH370 was observed from 1721:13 UTC [0121:13 MYT] to 1822:12 UTC [0222:12 MYT]
A 'blip' is a spot of light on a radar screen indicating the position of a detected aircraft.