🔍 Key Concepts

• Stability requirements for mobile offshore drilling units (MODUs) in severe weather • How lowering legs affects structural stresses and loads on a jack-up rig • Difference between environmental loads (wind, waves) and other types of load (variable load, leg strength, load line)

💭 Think About

• Ask yourself: When very high winds are expected, what is the main additional design consideration besides stability that the regulations and designers worry about for a jack-up’s legs and hull? • Think about what changes when you lower the legs further: does that mainly change how much cargo you can carry, the structural capability of the legs, the loads from the sea and wind, or something related to draft and marks? • Match each choice to a real-world design check: which one would actually be satisfied by lowering the legs a specific distance below the hull in a storm condition?

✅ Before You Answer

• Identify which choice is directly tied to wind, wave, and current effects rather than cargo or markings. • Ask whether lowering the legs is more about reducing stresses and moments from the environment, or about adjusting cargo capacity or draft marks. • Eliminate any option that deals primarily with cargo quantity or load line markings, since the question specifies very high winds.