The RAF Viking T Mkl is a variant of the Grob 103 Twin 2 Acro glider. It is a tandem 2 seat, mid wing glider with a T-tail and is made of Glass Fibre Reinforced Plastic (GRP) laminate. The glider has a wing span of 17.5 metres and a best glide ratio of 36:1. Equipped with a 720 channel VHF radio, the glider is Ideally suited to both basic and soaring training and is fully aerobatic (although HQAC does impose certain restrictions on aerobatic flying for safety reasons).  

The Viking glider was the successor of the Twin Astir Glider with a fixed six-inch main gear fitted behind the centre of gravity in a fairing and a nose wheel. The main wheel is equipped with a hydraulic brake. Modified ailerons produce a substantially improved roll response. Approach control is by top surface Schemmpp-Hith type airbrake's. The Royal Air Force acquired 100 Across (known as the Viking T. MK.1) for its air cadet training program.