Complex sentence: It had "twin screws", powered by two Caterpillar D343 turbo diesel engines, each producing about 450 HP. Although the nominal cruising speed was about 10 knots, the Vantuna could reach a maximum speed around 14 knots.
Split into simpler sentences: It had "twin screws", powered by two Caterpiller D343 turbo diesels engines, with about 450 HP each. The nominal cruising speed was about 10 knots, but could reach a maximum speed of about 14 knots.