As it happened, for example, with the British dirigible R-100. Airships were slug. Low-power motors do not allow them to develop a sufficiently high cruising speed. Speed has become one of the factors that gave the sky airplanes airships. A serious drawback airships, especially the giants of pre-war time was insufficient strength of the structure. […]

The upper limit of moisture which keeps the plastic properties of clay, called the boundary flow. With further increase of moisture the clay mass loses its ability to keep the form – it flows. The lower limit of moisture content of clay, which has plastic properties, called the plastic limit. Below this limit, the clay […]