Complex sentence: The nominal cruising speed is about 10 knots, but can reach a maximum speed of about 14 knots, fuel consumption raging from 8 gallons per hour to over 20 gallons per hour at the top speed.
Split into simpler sentences: The nominal cruising speed was about 10 knots, but could reach a maximum speed of about 14 knots. Fuel consumption ranged from 8 gallons per hour to over 20 gallons per hour at the top speed.