#1 - Nov. 14, 2012, 11:22 p.m.
The tank in the Steel Tide mission isn’t usable, upon turning in either direction it turns the full way and kicks you off the tank.
The Steel Tide Tank Bug
#7 - Jan. 10, 2013, 4:59 p.m.
https://forum-en.guildwars2.com/forum/game/story/The-Steel-Tide-Bugged/1177665
In the meantime, you can also use the nearby mortars to fight the Risen. The objective is based on killing X giants.