The flight path from Taipei, Taiwan, to Tianjin, China, does not go directly to Tianjin in a straight line.

Instead, it heads directly north, then banks left (west) before heading north again.

[![enter image description here][1]][1]  
(Flight CCA188, source: [FlightAware][2])  

Route: PIANO L3 VIOLA R596 OKATO W13 PINOT B221 OKTUG W506 HGH W554 DOGVI A470 PIX A593 VYK VYK9A/16R (source [VatAware][3])

Does anyone know why this is?


  [1]: https://i.sstatic.net/nqLM3.png
  [2]: https://fr.flightaware.com/live/flight/CCA188/history/20151101/1045Z/RCSS/ZBTJ
  [3]: http://vataware.com/flight/554ec8cea7656570cb000005