This is the third and the final one of the three reports concerning the wave-cancelling experiment on the high speed coaster M/S “KURENAI MARU”. This report will give the proceedings of ship's wave measurements in the experiments both on the 2.5 m model and on the full-scale ship together with the results of their stereo-analysis.
The quantitative analysis of the observed model's waves has definitely demonstrated the remarkkable wave-cancelling effects caused by the attached bulb F 4, which was theoretically designed for the Froude number F= 0.316, i.e. Vs= 17.60 knots.
As far as the model's waves, detailed wave-contour maps were obtained successfully at several Froude numbers including F=0.316, each in a couple for comparison between two cases : with and without the attached large bulb F 4.
Concerning the ship's waves at their full scale, it was planned to employ a helicopter Sikorsky S-55 C during the speed trials on March 13 and 16, 1961. Two different types of cameras were applied on the helicopter for filming the wave patterns of the running ship : a large sized aerial camera and a 16 mm portable cinecamera (coloured film).
Unfortunately, the bad weather prevented us from recording the ship's waves at her as built condition B 1 (on March 13), and this lost chance was partially recovered on March 16 thanks to the co-operation of the captain of her sister ship M/S “MURASAKI MARU”. She fortunately was on her daily service from Kobe to Takamatsu and was nearby the mile course off the Awaji Island. In Fig. 10 a remarkable difference of wave features can be observed between two syster ships which are running nearly abreast.