Steam catapults were developed in the 1950s and have been exceptionally reliable. For over fifty years at least one of the four catapults has been able to launch an aircraft 99.5% of the time.[23] However, there are a number of drawbacks. “The foremost deficiency is that the catapult operates without feedback control. With no feedback, there often occurs large transients in tow force that can damage or reduce the life of the airframe.”[24] The steam system is massive, inefficient (4–6%),[25] and hard to control.
Control problems with the system results in minimum and maximum weight limits. The minimum weight limit is above the weight of all UAVs. An inability to launch the latest additions to the Naval Air Forces is a restriction on operations that cannot continue into the next generation of aircraft carriers. The Electromagnetic Aircraft Launch System provides solutions to all these problems. An electromagnetic system is more efficient, smaller, lighter, more powerful, and easier to control. Increased control means that EMALS will be able to launch both heavier and lighter aircraft than the steam catapult. Also, the use of a controlled force will reduce the stress on airframes, resulting in less maintenance and a longer lifetime for the airframe. Unfortunately the power limitations for the Nimitz class make the installation of the recently developed EMALS impossible.
Electromagnetics will also be used in the new Advanced Arresting Gear system. The current system relies on hydraulics to slow and stop a landing aircraft. While effective, as demonstrated by more than fifty years of implementation, the AAG system offers a number of improvements. The current system is unable to capture UAVs without damaging them due to extreme stresses on the airframe. UAVs do not have the necessary mass to drive the large hydraulic piston used to trap heavier manned planes. By using electromagnetics the energy absorption is controlled by a turbo-electric engine. This makes the trap smoother and reduces shock on airframes. Even though the system will look the same on the flight deck it will be more flexible, safe, reliable, and require less maintenance and manning.[26]