The BS4 catapult assessment weighs performance against shipboard costs

Hydraulic catapults are introduced as the equipment used before steam became the preferred system. The quoted BS4 assessment considers weight, space and maintenance alongside launching performance. Although lighter than corresponding hydropneumatic equipment, the new system still places substantial weight and equipment high in the ship. Its greater performance promises more freedom in carrier operations and the use of higher-performance aircraft. The assessment also considers smaller, lighter aircraft achieving comparable performance and endurance. Further design improvements are expected because the system is still early in development. A later exchange notes that a breached hydraulic line loses pressure and fluid. Hydropneumatic catapults are nevertheless described as the workable option available at their technological level.