Heero asked Quatre to bring Wing Zero to him because it is faster for him to get on it right away. After Heero got onto his Gundam, he encountered Wufei. At this time, Wufei was beginning to have doubt toward the true meaning of justice. He felt that it didn't make sense in that he was still fighting and involved in a war while everything was at peace (when there's peace, there're no need for warrriors nor wars and Wufei was getting very confused about the very purpose of his involvement). (thetvdb.com)