Related Clues:

• Depth charge targets
• Ships' officers
• Per diem teachers
• Long lunches
• Underwater vessels, for short
• Poor boys
• Fill-ins
• Undersea travelers
• Second-stringers
• Some sandwiches
• Reserves on the bench
• Deli sandwiches
• Undersea vessels
• Sandwich shop purchases
• Advances when transport turns up from the south