抄録
In succession to previous reports methods for safely throwing mortar containers into the sea were studied.
At the present time a testing tank (60×60×230cm) provided with a glass plates in its front was newly constructed. Studies were carried on by photographing the state of falling model cylinders in this testing tank by means of stroboscope.
In the first place the drag coefficient was determined by the experiment, where model bakelite cylinders at their sidelong positions were thrown and the value of 0.63±0.02 was obtained. This value is closely identical with the value of 0.65, which had been calculated provided the ratio of the diameter of the cylinder to the height thereof had been 2:3, and with the value of 0.67 found from throwing experiment in the sea.
In the second place in case of throwing containers into the sea for the purpose of throwing the containers at a safety velocity, studies for determining various conditions, which parachutes attached to the containers must fulfil, were carried out.
