The COASTAL DRILLER, while in a normal...

Question 1 / 2707066636ee728f7522a1c517740

Question 1 of 2707066636ee728f7522a1c517740

The COASTAL DRILLER, while in a normal transit, experiences single amplitude rolling of three degrees. What is the minimum period of roll which does not exceed the design limits of the legs?

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Question 1 of 27070

The COASTAL DRILLER, while in a normal transit, experiences single amplitude rolling of three degrees. What is the minimum period of roll which does not exceed the design limits of the legs?

🔍 Key Concepts

• Roll period and what it tells you about how a vessel or mobile offshore drilling unit (MODU) moves in a seaway • Relationship between small roll angles (like 3°) and structural design limits of legs/supports • How drillship/jack-up or drilling unit leg design accounts for dynamic loads from rolling motion

💭 Think About

• Think about whether a very short roll period or a longer roll period creates higher dynamic loads on tall, relatively slender legs • Consider what kind of motion (fast/jerky vs slow/gentle) the leg structure is more sensitive to • Ask yourself if a structure designed with limited roll angle tolerances would be more conservative about rapid accelerations or about slow movements

✅ Before You Answer

• Compare which options represent rapid, snappy rolling versus slow, gentle rolling • Remember that for small roll angles, angular acceleration, not just angle, affects stress in the legs • Before choosing, decide which period range would most likely be regarded as safe within design limits for a normal transit condition, not storm survival

Question 1 of 27070

The COASTAL DRILLER, while in a normal transit, experiences single amplitude rolling of three degrees. What is the minimum period of roll which does not exceed the design limits of the legs?

1.5 seconds

3.0 seconds

5.5 seconds

7.0 seconds

Question 1 / 2707066636ee728f7522a1c517740

Question 1 of 2707066636ee728f7522a1c517740

The COASTAL DRILLER, while in a normal transit, experiences single amplitude rolling of three degrees. What is the minimum period of roll which does not exceed the design limits of the legs?

Back

Question 1 of 27070

The COASTAL DRILLER, while in a normal transit, experiences single amplitude rolling of three degrees. What is the minimum period of roll which does not exceed the design limits of the legs?