Abstract
Preventing keyless propeller from slipping requires the estimation of torque transmitted from shaft to propeller, as accurate as possible, taking the major parameters of ship, shch as main engine power or displacement into account. Experienced slip accidents show that it is necessary to consider the crash astern condition in estimation of torque used for determining pull-up length of keyless propeller. This paper describes how to estimate the increasing rate of the the torque in crash astern condition compared with that in steady condition through theoretical analysis and measured data. As a result, the authors found out that the increasing rate of torque can be approximately represented as a function of propeller diameter.
