The development of the Yugoslav sailplane ‘Triglav’

Abstract

The first beginning of the design goes back to 1947, when the sailplane was designed under the name Karavan But, following the increased experiences of the just established factory "Letov" in Ljubljana, where the ship was to be built the designers Stojan Hrovat and the author were able to redesign and modify the project so that an advanced sailplane should be the result.  The prototype flew in autumn 1948 and gave satisfactory results.  The first measurements were taken with simple instruments and no speed calibration. Only one point at the best gliding ratio velocity was controlled through a long glide in the quiet air with a height interval of 1200  m, over control marks on the ground  and with  time measurement.  Because of the great height interval, slight technical errors were of little importance.  The gliding ratio of 26, 4 was in good agreement with other measured points of the polar.  The acceptance tests completed the type was named "Triglav" after the highest mountain peak in Slovenia and first discussions about serial production began.  Two prototypes were built.