Evaluation of Publicly Known Facts

This page presents various facts which have been made known to the public and lists explanations, reasons or causes as suggested by officials, experts or other sources.

Some examples to start this page:-

Description

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MH370 did not make a distress call by radiotelephony

The aircraft was fitted with HF and VHF radios. Mayday is used for the highest level of distress signifying that 'an aircraft is threatened by grave and imminent danger and requests immediate assistance'. There was no Mayday call.

Possible reasons may include:-

• the aircraft was not threatened by grave or imminent danger
• none of the radios was functional
• the pilot(s) were maintaining a state of 'radio silence'
• the pilot(s) were unconscious or incapable of making the call
• the pilot(s) were not in control of the aircraft

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MH370 did not transmit an emergency signal by means other than radiotelephony

The aircraft was equipped with a transponder which can be programmed with a code to transmit in an emergency. The three emergency codes (known as squawk codes) are:

• 7500 indicates the aircraft has been hijacked
• 7600 advises communications have been lost (i.e. radio failure)
• 7700 is the highest level meaning an Emergency

These transmitted signals can be received by air traffic controllers and other aircraft.

MH370 did not transmit any of these codes.

Possible reasons may include:-

• the aircraft was not threatened by grave or imminent danger or had not been hijacked
• none of the transponder(s) was functional
• the pilot(s) were unconscious or incapable of programming the code(s)
• the pilot(s) were not in control of the aircraft

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High Frequency

Very High Frequency

International Civil Aviation Organisation

Department of Civil Aviation (Malaysia)

Greenwich Mean Time

Greenwich Mean Time. Superseded by Coordinated Universal Time (UTC)