I received a call from NBC News on Monday about an interesting angle on the Malaysia Airlines flight MH370 mystery.
Relatives of passengers on the missing aircraft apparently said they had dialed the cellphone numbers of loved ones on the flight and reported that the phones rang — several times in fact. Then the calls were terminated. What could this mean?
Nineteen family representatives signed a statement affirming that when they dialed their loved ones, their phones rang rather than immediately going to voice mail, according to a report published in China.org.cn. That has raised quite a few questions.
We all know that sometimes a call goes directly to voice mail. Other times, the network says the party you are calling is unavailable. There are all sorts of possible responses or messages, depending on the network and the circumstances. There is no common way every network handles every different attempted call.
This has caused confusion among friends, family and others following this event. I am sorry to say that when you hear ringing, it means nothing.
The way the wireless industry works is that each cellphone carrier simply chooses what happens when a call is placed. It is often different depending whether the calling party and receiving party are on the same network, on two different networks, in the same town or in different countries.
The missing Malaysia Airlines plane was flying over open water, far from any towers transmitting cellular signals. Smartphone batteries typically don’t last several days — however, the batteries in ordinary cellphones can last up to a week or so.
Many cellphone carriers worldwide have set up their systems to start the ringing sound immediately after the caller dials the last number and presses send. The idea is to signal that the call is being connected.
What happens next is that the network tries to find the phone being called in order to complete the connection. This lasts several seconds, during which the phone may ring several times. If the party you are dialing is found, the call is completed. If not, the call is disconnected.
When my wife calls me, she says it rings several times before I answer. However, when my phone starts ringing, I pick it up on the first ring. That difference is the time is takes the two different networks to talk together and connect the call.
If the calling phone and the receiving phone are on the same network, the call can connect more quickly. If they are on two different networks, it can take a bit longer. If the two networks are in different countries, it often takes even longer to connect.
The reason I’m writing this is just to provide clarification about what can be a very confusing process. When you hear the sound of a phone ringing several times, that does not mean it is ringing at the other end.
This missing Malaysia flight is one of the biggest mysteries we have ever seen. How does an airplane simply vanish? My prayers are with the travelers and their families who are anxiously waiting to learn what happened and what happens next.