A prototype of a 3000m-class underwater glider for virtual mooring is being developed by JAMSTEC (Japan Agency for Marine-Earth Science and Technology) with RIAM (Research Institute for Applied Mechanics) of Kyushu University. The vehicle houses an observation equipment and glides back and forth between the sea surface and the seabed collecting ocean data in a specific area (virtual mooring area) for more than one year. This paper summarizes our restudy on the hydrodynamic coefficients of the vehicle by constant acceleration tests and the simulated results of gliding angle control are compared with the experimental results carried out in a towing tank.