The F-15 is a famous American heavy fighter, with all versions of air superiority and ground attack; But why doesn’t the F-15 have a carrier-based version?
Back in the 1980s and 1990s, two types of heavy fighters symbolized American air power: the powerful F-15 Eagle and the sophisticated F-14 Tomcat. For a while, the US Navy really wanted a carrier-based version of the F-15, the F-15N version, also known as the “Sea Eagle”, proposed by McDonnell Douglas in 1971 at that time the F-15 was still in the pre-development stage.
The aircraft carrier-based fighter F-15N has made several modifications, such as the folding wings and a firmer landing gear. In McDonnell Douglas’s opinion, due to its excellent thrust-to-weight ratio and good visibility, the F-15 could easily be transformed into a carrier-based fighter, with superior features.
The early 1970s were a good time for McDonnell Douglas to introduce the F-15N. The F-14 had been in service since 1974, but was troubled by inefficient Pratt & Whitney TF30 engines. The F-15N will probably be faster and more maneuverable than the F-14, and also cheaper. At the time, the price of an F-14 was $38 million, while an Air Force F-15A cost only $28 million.
In terms of weapons, the original design of the F-15N was only armed with short-range Sidewinder and mid-range Sparrow air-to-air missiles, and an aviation cannon. The F-15N did not have the AIM-54 Phoenix super-long-range missile, which the Navy believed would be a good interceptor against Soviet bombers. Navy studies suggested that: If the F-15N was equipped with AIM-54 missiles and AN/AWG-9 long-range radar, the F-15N would be 4.5 tons heavier than the F-15A. As such, the F-15N would not offer any performance advantage over the F-14 Tomcat.
McDonnell Douglas and Hughes responded with the F-15N-PHX version. They kept the AIM-54 Phoenix missile, but removed the AN/AWG-9 radar to switch to an enhanced version of the AN/APG-63 radar, which fitted on the Air Force F-15A.
The Navy version of the F-15 was tested in March 1973. At this point, the F-14 program was in trouble, and a viable, lower-cost alternative was needed. In the end, the Navy stuck with the F-14 Tomcat, and the US Navy continued to develop a light fighter version, resulting in the F/A-18A.
So was the F-15N Sea Eagle a viable concept? This is the problem we’re seeing now with the F-35 situation. An aircraft that has to serve the purposes of different forces has to sacrifice performance in several areas. Therefore, to turn the F-15 into a carrier-based interceptor like the F-14, many design changes will be needed.
The problem of procurement of forces in the US Military is not simple. The Air Force and Navy have always had different requirements. In the 1970s, the US Air Force wanted a powerful, highly maneuverable fighter jet to replace their F-4 Phantoms. Ironically, the US Air Force once considered the F-14 as a replacement for the F-106 interceptor. The US Navy needed an interceptor with high-powered radar, long-range air-to-air missiles, to be able to intercept threats from afar.
And of course there was the political element. The Air Force and Navy will only buy planes from each other if politicians force them to do so. The F-15N Sea Eagle might have been a good idea to start with, but it would surely perish without support within the US government. And as a result, the US Air Force and Navy have their own main fighters as they like. But this has consumed more US resources.