noun
emergency surfacing drill (submarine)
Technical term used in naval and submarine contexts for a drill practicing rapid ascent to the surface in an emergency.
潜水艦の乗組員は定期的に緊急浮上訓練を行う。
The submarine crew regularly conducts emergency surfacing drills.
Compound of 緊急 (emergency), 浮上 (surfacing), and 訓練 (drill/training).