Aircraft

The backbone of the winch-launch fleet is the Grob 103 or as we know it, the Viking. A two seat glider used for AEG,GIC and AGT training.

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The Viking has no engine and is accelarated to its flying speed by different means. One method is aerotowing whereby a powered aircraft acts as a tug and pulls the glider off the ground and up to a pre-determined height by means of a towing cable. However, as a cadet, it is unlikely that you will experience this method of launching a glider. If you are affiliated to a Viking school you will experience the winch launch. A winch (picture left) is a series of drums on which are about 1,500 metres of strong, flexible, steel cable. The winch is powered by a powerful turbo engine.

A series of signals are given from the launch point caravan, instructing the winch driver when to launch. The cable is initally drawn in slowly to remove any slack in the cable, this signal consists of a slow flashing light and the signal is called 'take up slack'. When the cable is taught the winch driver recieves another signal called 'all out' at this ponit the winch driver applies alot more power to launch the glider into the air.

When the glider has reached its desired height the cable is released by the pilot and falls to earth, steadied by a parachute. it is then reled in by the winch before the next launch. The height the glider achieves depends on the wind strength, the speed at which the cable is being wound onto the drum and the length of the cable.

A winch launch normally lasts between 5-6 minutes. However in the warmer months the pilot can use thermals (warm rising air) to stay aloft for londger periods of time. The pilot will try and circle in the thermal to gain height.


Grob 103 - Viking

Max Speed - 135 knots

Recommended Speeds

  • Winch Launch - 50 - 60 knots

  • Aerotow - 50 - 75 knots

Minimum Sink

  • Dual 138ft/min at 46 knots

  • Solo - 126ft ft/min at 43 knots

  • Speed in circuit - 50 knots

  • Stalling speed:dual, brakes closed - 41 knots

Approach Speeds

  • Wind less than 10 knots - 55 knots

  • Wind greater than 10 knots - 60 knots

Dimensions

  • Span - 17.5 m (57.4 ft)

  • Length - 8.18 m (26.8ft)

  • Height - 1.55m (5.1ft)

  • Max All Up Weight - 625kg (1378 ib)