Blanik L-13 The LET Blanik L 13 aircraft was manufactured in the former Czechoslovakia between 1956 and 1978. Around 2,700 units, which were originally intended for military purposes, were produced. The Blanik is a two-seater with a wing spread of 16.2 metres and an effective length of 8.4 metres. Its basic weight is 292 kilograms and its limit speed is given as 252 km/h. Despite its relative age, the glider is still used today and is especially well suited for aerobatics due to its ideal construction design and its excellent power rating.