The F-16 is a single-engine fighter for the air force, while the F/A-18 is a carrier-based twin-engine fighter. That is the biggest difference between these two planes.
According to Military.com, The U.S. Navy is preparing to receive F-16 Fighting Falcon fighter jets from the Air Force as it moves to rid its inventory of legacy F/A-18 Hornet models used in its Reserve fleets, according to its fiscal 2022 budget request.
Approximately 55 Hornets are scheduled for retirement, with the jets operated primarily for adversary training to simulate the capabilities of enemy aircraft. The Navy already operates a small number of around 15 F-16s for this purpose, despite the Falcon being an Air Force jet which is not used by the Navy in a combat capacity.
The F-16 and F-18 have long been seen as rival programs, with the latter being closely based on the YF-17 prototype which was offered to the Air Force as an alternative to the F-16. Although the YF-17 built on the tried and tested design of the F-5, and benefitted from a higher flight ceiling and engine redundancy, the F-16 was chosen for its lower operational costs, easier maintenance, greater manoeuvrability and a longer range – while also being much cheaper to build. Although an F-16 modified to land on aircraft carriers was offered to the Navy, the benefits of having twin engines, which allowed a fighter to return to land or to its carrier if one engine failed, led the Navy to choose the F-18. For aggressor training, however, the F-16 is seen to have obvious benefits as a lighter and simpler airframe.
The F-16 Fighting Falcon and the F/A-18 Hornet are both classified as light fighters, intended to complement heavy fighters such as the F-15 and F-14. But they also have some major differences.
The F-16 has one engine – the F/A-18 has two. This is largely due to their differing operational environments. The F-16 operates from land bases, while the F/A-18 operates primarily from carriers. Of course, this also bears a lot on survivability. If an F-16 loses an engine, the pilot’s gotta grab the loud handle. An F/A-18, on the other hand, can limp back to the carrier.
The F-16 is tied to land bases – its landing gear cannot handle the shock of hitting a carrier deck. On the other hand, the F/A-18 can readily shift between a carrier operation and flying from land bases.