This paper describes performance of passenger boat “Michigan” which was constructed for the first time in Japan as the large scale ship with stern paddle wheel.
The data introduced include :
1) Design data of stern paddle wheel
2) Resistance and self-propulsion test results
3) Maneuvering characteristics
4) Comparison between screw propeller and paddle wheel with regard to the effect of disturbing the bottom of Lake Biwa.

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At the docking of a three-dimensional moving vehicle to a fixed base in deep water, an automatic system is indispensable to assure reliable and safe operation. In the paper, an automatic docking system using ropes is proposed for such situation, and basic concept and characteristics of the system are presented with some results of feasibility study of the system. In the system, ropes fixed to the base are connected to the vehicle by sonar trackers launched from the base, and then, the vehicle is docked to the base by the ropes controlled by a central controller in the base. Real time estimation of state variables of the vehicle, i. e. position, velocity and attitude of the vehicle, from the rope lengths, and the control of the vehicle by the ropes based on these information are essential in the system. To investigate practical feasibility of the system, especially those of real time state estimation and the vehicle control, simulation study is made using a small size mini-computer which can be installed in such underwater base. From the simulation results, it is shown that a near optimum filter can be effectively utilized to estimate the state variables of the moving vehicle, with which the vehicle can be controlled by the ropes with sufficient accuracy.

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Thermal environments in reefer hold of refrigerating cargo ship and cabin during air conditioning are controlled by turbulent air flow with adequate temperature. Such an air in enclosed space has tendency to form thermal layers in such cases that most of air flow is slow in speed and the location of supplied air inlet is either lower position for cool blow or upper position for hot blow.In the case of arising this phenomenon, the gradient of air temperature in vertical direction tends to be so large that it causes heat loss, cargo damage and uncomfortable circumstance.
In order to clarify the heat transfer for such case of forming thermal layers in enclosed space, flow velocity and air temperature in an air conditioned chamber of container type are measured in various conditions during heating up. Further, three dimensional analyses of heat convection in non-isotropic turbulent flow, described in 2nd report by finite element method, are carried out for models corresponding to measurements.
In general, it is very complicated to solve exactly the heat convectional equations. However, it is necessary to obtain easily the distribution of air temperature in enclosed space for the prediction and optimum design of thermal environment in designing stage of ship equipment.
In this paper, a new conception of heat penetrating rate in surrounding walls is introduced to constitute the thermal balance equation. And a simplified formula based on heat transfer equation is proposed for practical use to predict simply the distribution of air temperature as time proceeds. This formula is applied to the analyses of the measured value at air conditioned chamber for judging its justice. Reasonable agreement between the measured and predicted ones is shown.

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Two kinds of experiments were conducted in regular waves. One was to measure distribution of hydrodynamic impact pressure due to bottom slamming of a wooden model in fully loaded condition of a bulk carrier.
The other experiment was for longitudinal bending responses including whipping of an elastic model of the same hull form having elastic similarity to the actual ship in addition to geometric and hydrodynamic similarities.
Based upon these experimental results, discussions were made on natures of hydrodynamic impact and whipping moment, effects of elasticity to the ship responses and the relationship between impact and whipping moments.
It was concluded that the elastic model technique can be very useful to simulate actual hull girder responses in a model basin, the elasticity affects ship motions and hydrodynamic pressure little and that measured whipping moments can be correlated to the impact forces by taking “dynamic load factor” into account.

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A bulk carrier in the fully laden condition suffered disastrous structural damage in rough seas in the North Pacific Ocean off Japan where two systems of swells were dominant; one was regarded as a regular wave train of 89 m in height, and the other is irregular one of significant wave height 46 m. Her fore body before the mid-length of No.1 Cargo Hatch was bent upwards and was seperated from the main body soon. Forty days later, she sank during being towed to Wake Island. The process of the disaster is analyzed in the present paper from the viewpoint of hydro-elasticity on the basis of her captain's report on this event. It is concluded that the disaster was caused by buckling of the upper deck due to slamming impact in an unlucky superposition of the two systems of swells.

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