The Ford-class Carrier’s EMALS Catapult Is Changing Naval Aviation
The EMALS is an electromagnetic catapult that relies upon a linear induction motor, rather than a traditional steam piston, to launch aircraft.
The Ford-class aircraft carriers are the most expensive warships ever built. The price: $13 billion per unit. To put that number in perspective, consider that an Arleigh Burke destroyer costs just $2.5 billion. But the Ford-class is a special vessel, built to house thousands of sailors and dozens of aircraft and loaded with modern technology—the research and development of which drove the price tag up significantly. One of the more heralded technological additions to the Ford-class is the Electromagnetic Aircraft Launch System (EMALS). The EMALS is billed as a revolutionary new catapult system, which should improve the Ford’s sortie generation rate (SGR).
Introducing EMALS
The EMALS is an electromagnetic catapult that relies upon a linear induction motor, rather than a traditional steam piston, to launch aircraft. The linear induction motor, as the name implies, uses alternating AC currents to move an object in a straight, or linear, line. The object being moved, in the case of the EMALS, is an aircraft.
The benefit of swapping out the steam pistons for the EMALS is multifaceted. First, the EMALS can be more carefully calibrated, allowing for the launch of a wider variety of aircraft. Second, the EMALS regenerates faster than the steam piston, allowing for the launch of aircraft in quick succession. Third, the EMALS provides a gentler acceleration than the steam catapult, hence reducing wear and tear on the airframes that will be repeatedly subjected to catapult launches. In sum, the EMALS should improve the Ford’s SGR relative to preceding Nimitz-class carriers.
A carrier’s SGR is significant. Consider the purpose of the aircraft carrier: to launch aircraft; to generate sorties. Intuitively, a carrier that can generate more sorties has more value. A carrier that is lagging, because the catapult is slow to regenerate, or because aircraft are requiring extra maintenance, is less effective; a carrier that cannot generate sorties effectively can essentially defeat the purpose of having an aircraft carrier in the first place. And that’s not to suggest that the Nimitz was incapable of generating sorties—only that the Ford shouldgenerate more sorties.
Saying goodbye to steam
To be fair to the steam catapult system, it should be mentioned that steam has proven exceedingly reliable since first being developed in the 1950s. Carriers equipped with steam catapults almost always have at least one of their four catapults operational, meaning aircraft are always ready to be launched. Such reliability should not be taken for granted, especially as the Navy pivots are moving toward using new technologies that have unproven reliability. But the steam catapult does have some drawbacks. Perhaps most notably, steam catapults have a tendency to be over-powerful, thereby damaging aircraft and reducing the life of an airframe (which itself can cost many tens of millions). The over-power problem prohibits the launching of lighter aircraft; only heavy aircraft, like an F/A-18 Hornet or an E-2 Hawkeye, can be launched. This leaves out new, lightweight UAV aircraft, which the Navy intends to increasingly rely upon.
About the Author: Harrison Kass
Harrison Kass is a senior defense and national security writer with over 1,000 total pieces on issues involving global affairs. An attorney, pilot, guitarist, and minor pro hockey player, Harrison joined the US Air Force as a Pilot Trainee but was medically discharged. Harrison holds a BA from Lake Forest College, a JD from the University of Oregon, and an MA from New York University. Harrison listens to Dokken.
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