The purpose of this memorandum is to put forward a procedure for carrying out side thrusters trials to ensure that the results of such trials carried out on different occasions correctly reflect the comparative performance of the units and their effect on the ship concerned.

Several factors may influence the thrust measurement on such trials including wind forces on the hull and superstructure, depth of water, and the proximity of the dock and quay walls. Methods of dealing with these effects are described.

So far there has been no experimental confirmation of the feasibility of conducting trials in the manner suggested and the procedure is tentative only. It is intended to try this out as opportunity arises and it is hoped that Member Firms will also be interested in putting the recommendations into practice.

Appendix I details in tabular form the measurements required from the trials together with other relevant information.

Appendix II gives a method of calculating the wind forces on the ship.