What is the purpose of classifying fighters?

Question

Fighters are classified by generation, as explained in this answer. Given this Wikipedia sum up, some fighters are not clearly in a defined generation, especially for 4th generation subclasses. Thus people may not agree on a list of fighters that belongs to a generation.

Some of the previous generation (generation 4, 4+, 4.5, 4++) are still actively produced (e.g. Rafale, F/A-18E/F) while the F-22 (definitely 5th generation) is no longer in production.

Airframe designed a long time ago (e.g. the F-15, F/A-18) still receive updates that make it competitive on international market (the section about potential operator of the F/A-18 on Wikipedia give an overview for the F/A-18), even in front of 5th generation fighters (at least in Canada for the F/A-18 and the F-35)

Another capability we cannot rely on to define generation is stealth. The A-12 and more precisely its variant YF-12 was stealth supersonic aircraft with weapons (AIM-47) inside internal bays, but was not a 5th generation fighter. Moreover, since ECM can be fitted on a fighter, this fighter expose some stealth feature.

Given those facts, it seems that since the 4th generation, knowing a fighter is classified as a specific generation does not provide information about its production year, its capabilities nor its competitivity in front of other nation's fighters.

In short, since the 4th generation, generation does not provide reliable information about capabilities, features nor designed or production year.

What information does the generation of a fighter give? How useful it is to know a fighter belongs to a specific generation?

Answer 1

People like to classify things, to divide them into categories. Categorizing allows people to get an initial broad understanding of a complicated subject more quickly. It is therefore very useful for purposes such as marketing and articles aimed for people who aren't necessarily subject matter experts. However, classification is necessarily a crude tool that often isn't exact, leading to confusion and arguments about where the category boundaries lie.

People who are subject matter experts, such as designers of a new fighter plane, or military analysts trying to determine the capabilities of a new secret aircraft produced by other countries, presumably don't spend much time wondering into which category to put a given aircraft. Instead they focus their time on the details of the subject, the same details that are too much information for the person trying to get the quick grasp of the complicated subject.

To answer your questions specifically, knowing the generation of a fighter gives someone a rough idea of its capabilities, and allows the person to quickly compare a given fighter aircraft to other fighter aircraft. Knowing the generation of a fighter is useful for people who aren't experts on the subject who need a quick broad understanding of the capabilities of historic and modern fighter aircraft, and who need to know roughly where a given aircraft fits into the large picture.

Answer 2

To be clear, there is no “generation” classification for fighters. This was a marketing gimmick cooked up by defense OEMs to move hardware and keep Congress from axing pet projects. The generation thing appears in the 1990s in Lockheed Martin literature about the F-22, which at the time was in danger of being stillborne. Nobody referred to the ATF program, which sired the F-22, as a fifth generation fighter. It was a fighter program, albeit an advanced one.

Stealth, derived from the old Anglo Saxon word “stealeth” meaning to sneak up upon and overtake by surprise, is a generic term for a wide variety of technologies called Low Observable Technologies. They are intended to reduce the signature of a person, vehicle or structure, by identifying all means by which they can be detected by sensors. This includes visual, infrared, radar, thermal, acoustic, etc. LOT technology then attempts minimize the footprint made. Stealth appears to have been a media thing, similar to how Vespa mandarinia was dubbed ‘Murder Hornet’ - it sounds scary, which gets likes, clicks, airtime and column inches. The origins of the term stealth go back to the 1980s and were most closely attached to leaks about the Have Blue and Senior Trend programs which developed the F-117 attack aircraft. Stealth is also often associated with radar near invisibility and refer to aircraft whose shaping was derived from Pyotr Ufimsev’s research into accurately calculating RCS size. The B-2 “Stealth” bomber program was originally know to the public as the Advanced Technology Bomber (ATB). The term also got traction in Tom Clancy’s book Red Storm Rising, which featured the deployment of a fictional “F-19 Ghostrider stealth fighter” on a future European battlefield against the Soviets.

In short fighters are fighters, stealthy or not.

Answer 3

As you can see from the Wikipedia chart, the fact that the definitions vary depending on the publication means it's all just a kind of a construct in the minds of the ones who created it. In the end it's just a historical mental exercise with no particular applicability other than to be a useful shorthand when making a historical description of design over the years. As far as a practical application goes, not much.

Answer 4

Categorizing into groups such as this helps military pilots bundle tactics together to be briefed and practiced in training. Fighters within a generation have similar capabilities, and it is useful and practical to group them in such a way so as to be able to speak about them in broad terms.