I hear the term “fighter generation” a lot these days, such as Fourth-gen or Fifth-gen. What does that mean?
It’s a great question. A fighter generation is a period of time where aircraft were designed and built with similar technology, under a similar philosophy. There’s no clear-cut distinction between generations—engineers simply build the best aircraft they can and looking back we can broadly categorize where different aircraft belong. Fifth-generation aircraft represent the newest fighter technology. However, to understand what that means and what capabilities these aircraft bring to the table, we need to take a look at the previous generations.
The dawn of the jet age began during WWII with the first operations jet—the German Me-262. The United States, lagging in jet technology, fielded their first combat-capable jet in 1945. These and other first-generation aircraft were like their propeller-driven predecessors, except for their engines. They had little to no avionics and their primary weapon was the gun. Because jet engine technology was in its infancy, they had short lifespans and, if not delicately managed, were prone to flameouts—quickly turning them into gliders.
After the Korean War ended in 1953, second-generation fighters made their debut. One of the lessons learned during the war was that gunning a high-speed aircraft with a manual gunsight was incredibly difficult. Technology had also progressed to the point where missiles could be used to shoot down enemy aircraft. Combined with afterburning engines, this era gave rise to the interceptor: high-speed, high-altitude aircraft, like the F-104 Starfighter, that was designed to intercept Russian bomber formations and launch nuclear-tipped air-to-air missiles.
Third-generation aircraft arrived in the early 1960s. These aircraft placed an emphasis on a multi-role capability. Aircraft like the F-4 Phantom could carry a variety of air-to-air and air-to-ground weapons, including the first laser-guided smart-bombs. The gun was de-emphasized and, in some cases, eliminated. This, combined with subpar missile reliability, led to a lower-than-expected air-to-air kill ratio during the Vietnam War.
Fourth-generation aircraft addressed the missile-reliability issue by reemphasizing the importance of maneuverability and the within-visual-range dogfight. Nimble aircraft based on fly-by-wire control systems (instead of traditional cables and pulleys) were developed, which allowed inherently unstable designs like the F-16 Viper to fly. Avionics were also substantially improved, along with the pilot-to-aircraft interface. By placing the buttons on the stick and throttle, a pilot could execute thousands of commands without taking their hands off the controls, allowing for quicker reaction times and the ability to change settings under high G-forces.
Because several fourth-generation aircraft are still flying today, many include a fourth-and-a-half generation designation for aircraft that were upgraded or redesigned after the 1990s. Due to an exponential increase in computing power over the last 50 years, the fourth-generation aircraft rolling off the factory-line today–like the F-16V and the F-15EX—are massively improved from their original designs. Though they may look similar to their predecessors, their advanced integrated avionics suites allow for an order of magnitude increase in situational awareness.
Because fifth-generation aircraft were designed from the ground up nearly 30 years after their fourth-generation predecessors took flight, an entire article needs to be devoted to describing the new capabilities these aircraft bring to the fight. Make sure to keep an eye out for part 2!
Feature photo: U.S. Air Force photo by Senior Airman Mary Begy