March 27 (UPI) -- The Mexican Navy was searching the Caribbean and Gulf of Mexico on Friday for two missing aid boats bringing at least two tons of humanitarian aid to Cuba. The air-sea search and rescue operation involving naval vessels and military aircraft was launched after the catamaran sailboats, Friendship and Tiger Moth, with a multinational crew of at least nine, failed to arrive in Havana on Wednesday, the navy said. The flotilla, part of Nuestra America Convoy to Cuba, set off on the