What unconventional tactic did UDTs often use during their missions?

The unconventional tactic that UDTs often employed during their missions was nighttime underwater penetration. This method allowed the Underwater Demolition Teams to approach enemy beaches and coastal defenses undetected, utilizing the cover of darkness and the element of surprise to conduct reconnaissance, demolition, and sabotage operations. By entering the water at night, the UDTs could evade enemy surveillance and barriers, enabling them to gather crucial intelligence and prepare landing zones for amphibious assaults.

This tactic was particularly effective during World War II, as it minimized the risk of detection and maximized the chances of successful operations against fortified positions along coastlines. It demonstrated the UDTs' specialized training in underwater operations and their ability to conduct covert missions in challenging environments.

The other options provided do not accurately reflect the operational style of UDTs. Armored tank landings and massive frontal assaults are more characteristic of conventional military tactics that prioritize direct engagements rather than stealth and surprise. Deceptive aerial maneuvers are tactics typically associated with air forces rather than specialized naval units focused on underwater and coastal operations.