The captains of the ships sole responsibility is to navigate to Gaza. They know they will be under "embargo' inspection. As long as there is only humanitarian supply stuff , they will be able to drop off their loads and sail their ships back to home port. Remember people the sole purpose is to bring aid to the Gazans and not to confront the IDF.
Saudis warns U.S. that 9/11 responsibility law would erode investor confidence in America (Reuters)
from the article: Turkey group plans new Gaza flotilla with at least 15 ships