Couldn’t they afford to put a foward scaning and side scaning Sonars on the ship? Really, my guess is they were making a “hero run”, running fast at night with all Sonar and Radar off trying to be undetected and relying only on GPS and charts that hadn’t been updated..... and they stuffed it! Did somebody screw with the GPS signal?
Maybe it was intentional.
http://manilastandardtoday.com/www2/2012/06/01/military-wary-of-chinese-in-panatag-shoal/
June 1, 2012 - “MILITARY officials said Thursday they were worried that Chinese forces might put up markers or structures on the disputed Scarborough Shoal in the West Philippine Sea to bolser Beijing’s claim to the area.
“We will wake up one day and see markers or a small structure already planted inside or outside the lagoon to boost their claim,” said a ranking military official who spoke on condition of anonymity.”...................
As recently as fewer than five years ago, you've had US warships colliding with, among other things, fishing boats, rocky outposts and bridges.