Post date: Mar 19, 2014 4:3:11 PM
Next Media Online - The current limitations of transmission technology made it virtually impossible for passengers of the missing Malaysia Airlines flight to use smartphones to make contact with the ground, according to a report by AFP.
Many have questioned why no one on the missing Malaysia Airlines jet made phone calls to family and friends, as passengers did during the attacks on 911. Phone calls were possible back then as passengers were aware of the unfolding events; and it was believed that most of them used seatback phones to make the calls.To make calls, signals must be exchanged between mobile phones and the network in a process known as a ‘handshake’.
The airliner reportedly climbed to 45,000 feet and descended to 23,000 feet before disappearing from civilian radar. In an interview with AFP, telecommunication consultant Koh Chee Koon said terrestrial mobile networks in theory can still emit signals to devices at such a range.
But Koh said it would “require some luck” for successful transmissions because of the limited transmission capabilities of regular mobile phones, which cannot be used to make calls at an altitude above around 1,640 feet. The aircraft body also presented another barrier for signal transmissions.
The fact that no one was able to make ground contact also indicates that the airliner might be flying over waters, or that all passengers fell into unconsciousness, likely due to sudden changes in cabin pressure.
SOURCES: AFP
http://sg.news.yahoo.com/why-didnt-missing-jet-passengers-cellphones-071216203.html
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