The system is working well at Nyingchi airport in the Tibet autonomous region, which sits in a narrow valley between towering mountains. Without the navigation system, it's unlikely that planes would be able to land safely, according to a report by China Economic Weekly.

In May 2008, a devastating earthquake hit Wenchuan, Sichuan province, severing communication with the outside world. Rescue teams carried handheld navigation system terminals capable of sending or receiving 120 Chinese characters to communicate with the rescue headquarters.

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