7. When Postponed to Other Liens.—
An ordinary vessel mortgage is a very inferior grade of security because it is subordinate to all maritime liens and has only a qualified and dubious standing in the only courts which enforce them. One who advances money to a ship or her owner on mortgage is bound to know that the ship navigates on credit, and must continue to accumulate liens in order to earn freight, and that she may be pledged for bottomry or incur liability for torts. He is therefore postponed to sailors' wages, salvage, towage, advances, bottomry, general average, repairs, supplies, collision, personal injury, damage to cargo, breach of contract, penalties, and liens created by local law which the admiralty will enforce.
Here again the Ship Mortgage Act, 1920, makes a radical change in the case of "preferred mortgages" given upon American vessels to secure American investors. The Act makes the lien of a "preferred mortgage" inferior to liens of prior date and liens for damages arising out of tort, for wages of stevedores when employed directly by the owner, operator, master, ship's husband, or agent of the vessel, for wages of crew, general average and salvage, including contract salvage; but superior to all other liens, such for example as repairs, supplies, towage, pilotage, etc.