diff --git a/server/gameserver/roomobstacle.cc b/server/gameserver/roomobstacle.cc
index f45379f5..fcbd2d02 100644
--- a/server/gameserver/roomobstacle.cc
+++ b/server/gameserver/roomobstacle.cc
@@ -468,13 +468,9 @@ void RoomObstacle::ActiveAirDrop()
                  {
                      const mt::MapThing* thing_meta = meta;
                      if (thing_meta && thing_meta->summon_born_rad() > 0) {
-                         a8::Vec2 born_dir = a8::Vec2::UP;
-                         born_dir.Rotate(GetUniId());
-                         // 999
-#if 1
-#else
-                         born_pos = born_pos + born_dir * thing_meta->summon_born_rad();
-#endif
+                         glm::vec3 born_dir = GlmHelper::UP;
+                         GlmHelper::RotateY(born_dir, GetUniId());
+                         born_pos.AddGlmVec3(born_dir * (float)(thing_meta->summon_born_rad()));
                      }
                  }
                  room->frame_event.AddAirDrop(delay_time,