What were some of the dangers and consequences that portuguese sailors might have worried about when setting off on a journey along the west coast of africa in the early 1400s?

Though the Portuguese sailors had their maps and other navigational instruments with them, they encountered some problems and difficulties that they were not able to avoid. One was, they did not know what was the shape and how big Africa was. They did not know the routes yet and were unfamiliar with the trail.

Another is, though they did not have much trouble in sailing down the coast, getting back along the trail was a different story. They had a hard time sailing against the wind. 

australian plates collided into eurasian plates, and the himalayas formed. the andes mountain range the himalayas and the islands of japan form differently. the andes mountain range formed at the convergent boundary of an oceanic plate and continental plate.