A carrack or nao was a three or four-masted sailing ship developed by the Portuguese in the Mediterranean in the 15th century. The carrack was the beast of burden of the 16th century, carrying cargo and troops to faraway lands. It rode high in the water with the prominent forecastle (along with the usual sterncastle) giving it a characteristic “U” shape. It had a high rounded stern with an aftcastle and a forecastle and bowsprit at the stem. It was square-rigged on the foremast and mainmast and lateen-rigged on the mizzenmast.  The square rigging with a lateen mizzen is typical of the age but we see a second row of top sails needed to drive this heavy ship.  The high sides made it virtually impregnable to attack from small craft, which was often a problem in the East Indies. The forecastle located directly above the stem, with the bowsprit rising from its top made sailing to windward difficult and would disappear in gallions which come next. 

Large carracks had ample room for large crews, provisions and cargo required for east Indies trading. Their size and stability allowed mounting of cannons.  Carracks for exploration like the Santa Maria or Magellan’s Victoria (the first to circumnavigate the globe) were small, about 90 tons; but merchant ships would average 250-500 tons with a crew of 40-80 and some war ships went up to 1000 tons. The average speed was about 80 miles/day and the trip to India took 6 to 8 months each way.  

Carracks were the first proper ocean-going ships in Europe; large enough to be stable in heavy seas, and roomy enough to carry provisions for long voyages. They were the ships in which the Spanish and Portuguese explored the world in the 15th and 16th centuries. In Spanish this type was called carraca or nao, while in Portuguese it was called nau (both of which meant simply “ship”). In French it was nef.  English military carracks were called great ships.

The carrack was the high seas beast of burden of choice and has been described as the “perfected transport ship”.-

• it offered the space for crew, provisions and also cargo.
• they were virtually impregnable to attack from small craft, which was often a problem in the East Indies.
• their ability to carry cargo and provisions made them independent of ports en route, and so they had a longer range using the most efficient route.
• the combination of four sails allowed for a fair degree of flexibility – the large square sales provided propulsion, but were reduced in size during storms. The smaller sails at bow and stern allowed for manouvering, and the lateen sails allowed for sailing across the wind.
• the stable deck allowed for placement of guns, thus making the vessel an effective gun platform. This fact would greatly assist the Portuguese in convincing non-compliant rulers like the Samoothiri Raja in Asia.

However, the large superstructures of these ships, made them prone to toppling in strong winds.  Beginning in 1570 the Englishman John Hawkins experimented with a design in which the high forecastle is eliminated, proving that a ship with high stern and relatively low bow is faster and more maneuverable.  Hawkins’ “low charged” design, which acquired the general name of galleon became the standard form for all the large ships until the late 18th century.

Wikipedia