The Viking TMk1 aircraft is a conventional high performance 2 seat tandem glider of Glass Reinforced Plastic (GRP) monocoque construction, manufactured by Grob Aerospace. The aircraft is of T-tail configuration, and is fitted with a non retractable undercarriage and upper surface Schempp-Hirth type airbrakes.
The Viking, known in the Civilian World as the G103 Twin II is the successor of the original G103 Twin Astir with a nose wheel and a fixed six-inch main gear fitted behind the center of gravity - The main wheel is equipped with a hydraulic brake. Modified ailerons produce a substantially improved roll response compared to the previous model. The Viking has had some minor modifications from the civilian variants to make it suitable for Air Cadet flying.
The Viking can be launched either by winch or by aerotow from a powered tug aircraft. At 615 VGS, all launching is done by winch, and typically will achieve around 1000ft above airfield level. Normal launch speeds are between 55-60 knots, and once trimmed after the launch the aircraft is flown at 50 knots for the majority of time. For the normal range of aircraft weights, approach speeds are 55/60 knots, dependant on wind conditions on the day. The Viking is able to land in a crosswind component of up to 11 knots.
The Viking is also permitted to carry out a limited number of aerobatic manoeuvres subject to crew qualification. These include loops, chandelles, and lazy eights. The aircraft is very manoeuvrable and up to 98 knots has airframe acceleration limits of +5.7g to -3.7g, although operationally these are restricted to lower values to preserve airframe life.
All conventional gliding schools use the Munster Van Gelder winch to launch their aircraft. Cables are pulled from the winch across the airfield, and are then attached to the aircraft. After having taken any slack from the cable by pulling it in slowly, the winch will increase power considerably to pull the aircraft through the air to launch it. The Viking will achieve speeds of between 55-60 knots during launch.
Aircraft will normally achieve heights of around 1000ft from a winch launch at 615, but in favourable conditions have been known to reach 1600ft.
Winching is normally done by more junior members of staff, but all grades must stay current with winching operations. Winch driver training is usually given to new staff soon after they join and students will be trained in all weather conditions and emergency procedures. They will undertake a considerable amount of practice dual winching until competent to take the winch drivers test.
Signals are given to the winch a light mounted on a mast on the launch point control caravan. A radio is also used to communicate with the launch point.
Landrovers are used widely in gliding squadron operations. Their tasks include retrieving gliders from their landing roll, towing the launch point control caravan, and also for cadet and staff transport both on the airfield and off.
The launch point is the busiest place on the airfield during operations. Aircraft may be launching, landing, or retrieving, making it necessary for there to be a high level of supervision from the launch point marshall, and also from the Duty Instructor who is in overall charge of the airfield.
The caravan serves a number of purposes in gliding school operations. Most importantly, it is where the Duty Instructor (DI) sits and runs the airfield operations. The DI will sit at the top of the caravan, which is raised to give a good view, and is responsible for achieving the daily task, whilst ensuring all protocols are followed by everyone on the airfield.
The back of the caravan may be used by instructors to brief students before a sortie or as a shelter during times of bad weather.
The tractor is used to tow the MVG Winch as the Defender Landrovers are too light to safely move it. It is also used to tow cables from the winch to the launch point.