Roelfzema led fifteen such highly dangerous small-boat missions to the shores of the Netherlands. He was in charge of the insertion mission, while a Royal Navy lieutenant was in charge of the motor torpedo boat carrying them. The small group would wait for the dark of a moonless night to attempt their missions, with Roelfzema going ashore with whoever was being dropped. 108 such returned to the Netherlands by parachute or boat to support the resistance. Only half survived the war.