Lion class and the German speed challenge

Lion and the Indefatigables were built concurrently because they had different intended roles. Lion's 42 Yarrow boilers produced 70,000 shaft horsepower, giving the class the speed needed to counter German battlecruisers. The Royal Navy already expected to field the larger battle fleet, so these ships were intended to delay or damage German battlecruisers before they could exploit their speed against it. Their task called for running engagements and manoeuvre that left damaged opponents vulnerable to British battleships. Their 13.5-inch guns and greater cost accompanied a different tactical requirement from that of the Dominion station ships.