The DEEP DRILLER, at a draft of 60 feet, has -3,600 ft-tons of transverse moments. How much ballast should be transferred between tanks 10P and 10S to level the unit in list?

Correct Answer: Option A — 25.1 long tons

Transverse shifting moments are compensated by dividing the correcting moment by the transverse distance between tank centers. Per stability principles in 46 CFR, transferring 25.1 long tons across the specific arm generates the opposing 3,600 ft-tons moment required to return the MODU upright.