In the 1970s, the U.S. Navy sought to replace the F-14 Tomcat with a navalized version of the F-15, dubbed the F-15N Sea Eagle.

-Designed by McDonnell Douglas, this variant aimed to be lighter and more maneuverable but faced weight issues due to the inclusion of AIM-54 Phoenix missiles and the AN/AWG-9 radar. Despite efforts to adapt the F-15's AN/APG-63 radar for carrier use, the project failed to meet the Navy's requirements.

-The F-14 Tomcat remained in service, ultimately proving the better choice for carrier operations due to its superior maneuverability and combat record, despite its engine issues.

The F-15N Sea Eagle: A Missed Opportunity for Naval Aviation

In a great example of, “if ain’t broke, don’t fix it,” the U.S. Navy in the 1970s tried to replace possibly its greatest warplane, the F-14 Tomcat, with a newer, lighter aircraft. The Navy looked to McDonnell Douglas to build a “navalized” variant of the F-15 Flying Eagle the company had created for the U.S. Air Force. 

This F-15N Sea Eagle would be lighter, with a wing hinge to ensure the bird fit into the cramped quarters of an aircraft carrier’s fighter bay. It was outfitted with an arresting hook, and it had strengthened landing gear for carrier landings.

But this naval version of the F-15 fell afoul of the Navy’s weight reduction requirements. The inclusion of AIM-54 Phoenix missiles and the AN/AWG-9 radar system needed to aim them added another 10,000 pounds to the F-15N. 

It would not be lighter and more maneuverable than the F-14 Tomcat. Designers needed to reduce its weight. 

The Navy Really Tried to Make the F-15N Sea Eagle Fly

The designers at McDonnell Douglas did not give up. They enlisted the help of Hughes Aircraft, the maker of the AIM-54 Phoenix and the AN/AWG-9, to modify the Air Force’s F-15 AN/APG-63 to work with the Phoenix. But McDonnell Douglas still could not make the F-14N work. 

To understand why the Navy wanted to retire their iconic F-14 Tomcat, one needs to know the iconic bird’s flaws and why the Navy saw the Sea Eagle as a possible solution to them. 

It starts with the F-14’s engines. 

The Reason Why the Navy Wanted to Replace the F-14 Tomcat

The F-14 Tomcat’s powerful TF-34 engines ensured speed. The Tomcat could cruise at Mach 2.3, and its innovative variable-sweep wing design gave the bird additional maneuverability at any speed. These wings made the F-14 an astounding dogfighter, too, because they gave the Tomcat a tighter turn capability. It could outmaneuver and end-run almost any attacking Soviet plane.

TF-34 engines, however, were noted to be far too sensitive for the F-14 Tomcat’s mission set. The F-14 routinely suffered compressor stalls in its engines when engaging in a high angle of attack or when throttling the engine too quickly. Of course, in a dogfight, attacking at high angles or rapidly throttling the engines could be the difference between life and death. 

The Navy lost forty F-14s to compressor stalls over the course of the Tomcat’s service life.

There were other issues related to the engine, and all these problems meant that the Tomcats were expensive to build – and even costlier to maintain. It makes sense that the Pentagon would want to phase them out for cheaper, lighter, and more maneuverable warbirds. And the Air Force loved their variant of the F-15, making it even more attractive for the Navy to seek a version of their own.

The F-15N Sea Eagle Wasn’t the Only Time the Navy Tried to Align with the Air Force

The Navy has tried multiple times to purchase a variant of an air superiority warplane that was initially slated for the Air Force’s exclusive use. The F-15N Sea Eagle is one example – the F-22 Raptor and the F-35 Lightning II became others. 

Of these three, only the F-35 became a craft used not only by the Air Force, but also the Marines and the Navy.

Despite all attempts to solve the problem, the F-15N Sea Raptor could not carry the Navy’s beloved AIM-54 Phoenix missile. 

That left the F-14 Tomcat to continue as the Navy’s premier carrier-based warplane for years thereafter. The F-15N remains an interesting “What If?” in the annals of America’s defense projects. 

The F-14 Tomcat was the Right Choice

Ultimately, the Navy made the right choice in keeping the F-14 Tomcat. That warplane’s storied record of service and its iconic image in the minds of most Americans of a certain age (thanks in no small part to its starring role in the 1980s hit movie Top Gun) reflect that it is a highly effective carrier-based warplane. 

Just because the F-15 was one of the most storied Air Force warbirds does not mean it would have translated well to carrier operations for the Navy, which have fundamentally different requirements and place far different strains on warplanes. 

Given the early problems in the F-15N’s design phase, one can only imagine the complications and cost overruns if the warplane had been developed.

About the Author 

Brandon J. Weichert, a National Interest national security analyst, is a former Congressional staffer and geopolitical analyst who is a contributor at The Washington Times, the Asia Times, and The-Pipeline. He is the author of Winning Space: How America Remains a Superpower, Biohacked: China’s Race to Control Life, and The Shadow War: Iran’s Quest for Supremacy. His next book, A Disaster of Our Own Making: How the West Lost Ukraine, is due October 22 from Encounter Books. Weichert can be followed via Twitter @WeTheBrandon.

Image Credit: Creative Commons.