MH370 Timeline - Pre-Flight/1554:31 UTC

23:54:31 MYT Friday, 7 March 2014

This page provides details for events related to Malaysia Airlines Flight MH370 which occurred at or near the time of 23:54:31 MYT Friday, 7 March 2014.
Note: Malaysian Time (MYT) is Coordinated Universal Time (UTC) plus 8 hours. Return to Timeline

Summary

Malaysia Airlines Operations Centre contacted MH370 by sending an ACARS message (over VHF) suggesting that VHF3 be switched (from data) to voice if the SATCOM system was operational (serviceable). Future communications to and from the aircraft by ACARS would then be (automatically) sent via the SATCOM system.

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Event Details

1. Safety Investigation Report MH370/01/2018 Appendix 1.9A

   
   

   Time 15:54:31	Trans 46817955	Direction Outgoing Uplink	AN 9M-MRO	FI MH0370	Medium KUL	Machine MHKULKJACM001	Raw DTG 071554	SMI CMD	Application RELAY
   Status Uplink Sent		Message Type Frequency Auto-tune -- Frequency Auto-tune B777			Source/Destination BKKXCXA

   QU BKKXCXA
   .DPCCAMH 071554
   CMD
   AN 9M-MRO/FI MH0370/GL KUL/MA 988I
   - QUDPCCAMH~1RA101071554
   Message:
   SWITCH VHF3 TO VOICE
   (131.550)
   IF SATCOM SERVICABLE
   FROM MH OPS

   
   

   Time 15:54:31	Trans 46817955	Direction Outgoing Ground	AN 9M-MRO	FI MH0370	Medium KUL	Machine MHKULKJACM001	Raw DTG 071554	SMI CMD	Application BATAPCNX
   Status Routed		Message Type			Source/Destination BATAP_TO_MSW

   QU BKKXCXA
   .DPCCAMH 071554
   CMD
   AN 9M-MRO/FI MH0370/GL KUL/MA 988I
   - QUDPCCAMH~1RA101071554
   Message:
   SWITCH VHF3 TO VOICE
   (131.550)
   IF SATCOM SERVICABLE
   FROM MH OPS

   
   

   Time 15:54:36	Trans 46817955	Direction Incoming Downlink	AN 9M-MRO	FI MH0370	Medium KUL	Machine MHKULKJACM001	Raw DTG 071554	SMI MAS	Application RELAY
   Status Normal		Message Type MAS-S (successful)			Source/Destination BKKXCXA

   QU DPCCAMH
   .BKKXCXA 071554
   MAS
   AN 9M-MRO/FI MH0/MA 988S
   DT BKK KUL 071554 S05A

   
   

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Notes

1. ACARS can send data via the satellite communications system (SATCOM) or over a VHF data-link. The VHF radio must be switched from voice to data for this to occur.
2. VHF is commonly used at or near an airport, where the service provider has a transceiver to provide the ACARS service.
3. It seems that for flight MH370, ACARS was initially communicating via VHF.
4. This message from Malaysia Airlines Operations Centre suggests that the VHF radio be switched to voice-only, using channel 131.550 MHz - if the SATCOM is serviceable, meaning that the SATCOM could transmit and receive future ACARS messages.
5. This ACARS message was included in the Safety Investigation Report MH370/01/2018 Appendix 1.9A but not in the previous version Factual Information MH370/01/15 Appendix 1.9A.

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Documents and Related Articles

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Malaysian Time (MYT) is Coordinated Universal Time (UTC) + 8 hours

Aircraft Communication and Reporting System

Very High Frequency

satellite communications from ground to the aircraft earth station

Aircraft Number

Aircraft Registration Number for the Boeing 777 used for Flight MH370. More Info

Flight ID

Flight ID MH370

Kuala Lumpur

Unique hardware (machine) ID

Date and Time (UTC) in DD/HH/MM format

Date and Time (UTC) in DD/HH/MM format

Standard Message Identifier

Boeing 777 aircraft

Aircraft Number (Registration) 9M-MRO

Valid Flight ID: MH370

Operations

satellite communication from the aircraft to the ground earth station

Malaysia Airline Systems

Invalid Flight ID: MH for Malaysia Airlines but no flight number

Satellite Communications

Megahertz