Exam Question

### (a) Objectives of a Satisfactory Propeller Shaft Alignment
A satisfactory propeller shaft alignment is critical for the reliability and efficiency of the ship's entire propulsion plant. The primary objectives are:
1. **Uniform Load Distribution on Bearings**: To ensure that the static and dynamic loads on all bearings (main engine, intermediate, and sterntube bearings) are distributed according to the designer's specifications. This prevents overloading of any single bearing, which could lead to wiping of white metal, breakdown of the hydrodynamic oil film, and catastrophic failure.
2. **Minimization of Bending Stresses**: To ensure that the shafting system operates with minimal bending stresses under all operating conditions. This is crucial for preventing fatigue failure of the shaft material, especially in the vicinity of stress concentrations like keyways or coupling flanges.