 So in order to return to his intended course he must travel 5.5 × 26 = 143 miles on ENE.In other words, he needs to hold his ENE bearing for 143 miles; once that distance is travelled, he should straighten his ship East, and he will be exactly on the intended course.The final column ("avanzo di ritorno") gives the length on the intended course he has made good by his return travel.