The new F-15 combat aircraft that Boeing is pitching to the U.S. Air Force would have a single-seat cockpit and a host of new weapons, including anti-ship missiles, Defense One has learned.

If the Air Force bites, the so-called F-15X would be the Pentagon's first new Eagles since a 2002 purchase of the air-to-ground variant known as the F-15E Strike Eagle. But various allies have purchased newer variants of the Cold War air-superiority fighter, as recently as last year. The X version would largely resemble the ones Qatar ordered in 2017, tuned up with the latest technology for the new era of great-power competition envisioned in the Pentagon’s National Defense Strategy, according to people with knowledge of the plane’s development.

Boeing officials declined to comment.

The Air Force and Boeing have been talking about how new F-15Xs would be cheaper to operate than the current fleet of F-15s, which date as far back as the early 1980s. The talks have been going on for over a year, according to sources with knowledge of the discussions.

The X variant would benefit from upgrades funded by allies who have bought F-15s: Saudi Arabia, Qatar, Singapore and South Korea, which have collectively spent about $5 billion to develop new technology for their jets, the sources said. Compared to the Air Force’s existing F-15s, the new ones would have better flight controls, displays, and radars, and more powerful engines that allow the planes to carry a larger payload.

Like the air-to-air F-15C, and unlike the Strike Eagles, the new F-15X would have just one seat. Large digital display screens would replace the analog dials inside older F-15s. The planes could carry all of the existing equipment, like targeting pods, used across the existing Eagle fleet. The F-15X will also be able to carry anti-ship weapons that allies have paid to test and install. In all, the plane could carry 29,000 pounds of weapons.

The F-15’s range, speed and payload separates it from other fighter jets in the U.S. military. “There’s really nothing like it,” said Richard Aboulafia, vice president for analysis at the Teal Group, a Virginia-based consulting firm.

The additional weapons would allow the plans to fly new missions. It is expected to cost about $27,000 per hour to fly the F-15X. That’s about $5,000 less than an F-15E.

Currently, F-15Cs used by the Air National Guard to defend the continental United States. Other C squadrons based in England and Japan. F-15Es are primarily based in North Carolina, Idaho and England.

The Air Force is amid a sweeping review that is examining the mix of planes in its fleet, which senior officials are quick to point out is the smallest and oldest in the service’s history.

The F-15X is being pitched to complement existing F-22 Raptors and F-35 Joint Strike Fighters, to handle various missions where there is little risk of being shot down by surface-to-air missiles.

The view of only flying stealthy, fifth-generation fighters solo into battle without a complement of other other jets “appears to be going away,” Aboulafia said.

Still, he said, it's “unlikely but not inconceivable.”

Congress has been supportive of the F-15 program. The just-out-of-conference 2019 National Defense Authorization Act includes about $1 billion for a host of upgrades to existing F-15s, including electronic warfare.

People with knowledge of the program say the new equipment being purchased for the oldest F-15Cs could be installed on the new X variant.

Looking to the future, the sources said, the F-15X is ideally suited to carry hypersonic weapons.