A surface minelayer could carry far more mines than a submarine, shortening a risky mission to a single fast run. The intended sequence was to approach under darkness, sow a dense field, and leave before the enemy recognized the intrusion. Pre-radar search and limited night flying made the ship harder to locate once it withdrew. High speed then widened the search area after dawn. Payload, darkness, and velocity worked as one tactical system.
Chapter · 3:55-6:04
The dash-in, dash-out minefield mission
A fast surface minelayer could carry a dense load, approach at night, lay it in one run, and be gone before search aircraft could find it.