Egyptians in the New World?

[Sean Manning]

would it make sense if the main character of my book, who is going to be the son of Gaius Suetonius Paulinos (He was the first roman to cross the Atlas Mnts. and traveled all the way to the Senegal River by land), has ships that are built like Liburnae or Quinquermes but with larger hulls and 2 instead of one sail? He has reasoning behind this because he is intending on embarking on an expedition around the western coast of Africa. As his large fleet reaches the Bay of Guinea they are swept by a current and carried to the middle of the Atlantic. After several weeks they land at the northeastern coast of South America.

Educated Romans would have remembered Herodotus' story about the Phoenecian trade with the a place in west Africa where the natives had gold (4.196). That (or trying to reach barbarians who the other merchants haven't reached yet) might be another reason to send a fleet in that direction, but you would have to research whether the trade was still in existence.

Proper galleys would run out of food and water in a few days (water jars were heavy and bulks, and rowers need a lot of food and water), but some ships were hybrids between galleys and roundships. Lionel Casson's books on ancient ships are a good place to start.