(NewsNation) — The U.S. Air Force awarded a $13.08 billion contract to the Sierra Nevada Corp. to replace the service’s E-4B “Doomsday” plane, designed to withstand nuclear war.

The aerospace and defense company is tasked with developing a successor to what some call the “Doomsday” plane for its purported ability to survive a nuclear war. The Survivable Airborne Operations Center (SAOC) project is intended to replace an older aircraft approaching the end of its service life, Reuters reported, citing an Air Force spokesperson.

The Sierra Nevada Corp. is expected to complete its work by 2036.

Retired Lt. Gen. Richard Newton, a NewsNation senior national contributor, joined “NewsNation Now” to break down why the upgrade is happening and what it means.

“It’s been many decades since this aircraft has been effectively put into service, and it’s done a great job … but it’s now time to update the aircraft and modernize it,” Newton said.

What is a “Doomsday” plane?

The nation’s current model, known as the E-4B “Nightwatch,” is a militarized version of a Boeing 747-200. The high-altitude airplane is capable of refueling in flight and is divided into six functional work areas, according to the U.S. Air Force.

At 231 feet in length and 195 feet in wingspan, the aircraft has an advanced satellite communications system, a conference room, a communications center, and nuclear and thermal effects shielding. It can be refueled mid-air and can operate for 35.4 hours.

It’s protected against the effects of electromagnetic pulses and can foster worldwide communication for senior leaders.

Why does the Air Force have “Doomsday” planes?

In the event of a national emergency or destruction of ground command centers, the planes can act as a “highly survivable” communications and control center so leaders can issue emergency orders.

The E-4B also offers support to the Federal Emergency Management Agency, which helps aid in communication in post-natural disaster relief efforts.

However, the current fleet is due for an upgrade.

Over the next several years, Sierra Nevada will build SAOC to include modern, secure communication and planning capabilities, according to DefenseNews.

Why are the upgrades happening now?

The Air Force currently operates four E-4B aircraft with at least one on alert at all times, Reuters reported. The current fleet, however, relies on parts that are increasingly becoming obsolete, making the vehicles difficult and costly to maintain.

Although the aircraft are designed to withstand nuclear blasts, upgrades to the planes aren’t ushering in an impending nuclear disaster, Newton said.

He said the U.S. government must instead keep pace with global threats and modern technology.

“Certainly, you’ve got Russia invading Ukraine,” Newton said. “You’ve got Israel being attacked by Hamas and recently by Iran. China is ever-growing their military forces and their nuclear forces as well. It’s now time for the United States to lead, (and) this is why we need to pay very close attention to our adversaries but also continue to modernize our military capabilities.”

Reuters contributed to this story.